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335 Commits (8a7f97b902f4fb0d94b355b6b3f1fbd7154cafb9)

Author SHA1 Message Date
Mike Rapoport 8a7f97b902 treewide: add checks for the return value of memblock_alloc*()
Add check for the return value of memblock_alloc*() functions and call
panic() in case of error.  The panic message repeats the one used by
panicing memblock allocators with adjustment of parameters to include
only relevant ones.

The replacement was mostly automated with semantic patches like the one
below with manual massaging of format strings.

  @@
  expression ptr, size, align;
  @@
  ptr = memblock_alloc(size, align);
  + if (!ptr)
  + 	panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align);

[anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type]
  Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org
[rppt@linux.ibm.com: fix format strings for panics after memblock_alloc]
  Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com
[rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails]
  Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx
[akpm@linux-foundation.org: fix xtensa printk warning]
Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Guo Ren <ren_guo@c-sky.com>		[c-sky]
Acked-by: Paul Burton <paul.burton@mips.com>		[MIPS]
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>	[s390]
Reviewed-by: Juergen Gross <jgross@suse.com>		[Xen]
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Acked-by: Max Filippov <jcmvbkbc@gmail.com>		[xtensa]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12 10:04:02 -07:00
Mike Rapoport 9415673e3e arch: use memblock_alloc() instead of memblock_alloc_from(size, align, 0)
The last parameter of memblock_alloc_from() is the lower limit for the
memory allocation.  When it is 0, the call is equivalent to
memblock_alloc().

Link: http://lkml.kernel.org/r/1548057848-15136-13-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Paul Burton <paul.burton@mips.com> # MIPS part
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Guo Ren <ren_guo@c-sky.com>				[c-sky]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Juergen Gross <jgross@suse.com>			[Xen]
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12 10:04:01 -07:00
Linus Torvalds d9862cfbe2 Here's the main MIPS pull request for v5.1:
- Support for the MIPSr6 MemoryMapID register & Global INValidate TLB
   (GINVT) instructions, allowing for more efficient TLB maintenance when
   running on a CPU such as the I6500 that supports these.
 
 - Enable huge page support for MIPS64r6.
 
 - Optimize post-DMA cache sync by removing that code entirely for kernel
   configurations in which we know it won't be needed.
 
 - The number of pages allocated for interrupt stacks is now calculated
   correctly, where before we would wastefully allocate too much memory
   in some configurations.
 
 - The ath79 platform migrates to devicetree.
 
 - The bcm47xx platform sees fixes for the Buffalo WHR-G54S board.
 
 - The ingenic/jz4740 platform gains support for appended devicetrees.
 
 - The cavium_octeon, lantiq, loongson32 & sgi-ip27 platforms all see
   cleanups as do various pieces of core architecture code.
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Merge tag 'mips_5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Paul Burton:

 - Support for the MIPSr6 MemoryMapID register & Global INValidate TLB
   (GINVT) instructions, allowing for more efficient TLB maintenance
   when running on a CPU such as the I6500 that supports these.

 - Enable huge page support for MIPS64r6.

 - Optimize post-DMA cache sync by removing that code entirely for
   kernel configurations in which we know it won't be needed.

 - The number of pages allocated for interrupt stacks is now calculated
   correctly, where before we would wastefully allocate too much memory
   in some configurations.

 - The ath79 platform migrates to devicetree.

 - The bcm47xx platform sees fixes for the Buffalo WHR-G54S board.

 - The ingenic/jz4740 platform gains support for appended devicetrees.

 - The cavium_octeon, lantiq, loongson32 & sgi-ip27 platforms all see
   cleanups as do various pieces of core architecture code.

* tag 'mips_5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (66 commits)
  MIPS: lantiq: Remove separate GPHY Firmware loader
  MIPS: ingenic: Add support for appended devicetree
  MIPS: SGI-IP27: rework HUB interrupts
  MIPS: SGI-IP27: do boot CPU init later
  MIPS: SGI-IP27: do xtalk scanning later
  MIPS: SGI-IP27: use pr_info/pr_emerg and pr_cont to fix output
  MIPS: SGI-IP27: clean up bridge access and header files
  MIPS: SGI-IP27: get rid of volatile and hubreg_t
  MIPS: irq: Allocate accurate order pages for irq stack
  MIPS: dma-noncoherent: Remove bogus condition in dma_sync_phys()
  MIPS: eBPF: Remove REG_32BIT_ZERO_EX
  MIPS: eBPF: Always return sign extended 32b values
  MIPS: CM: Fix indentation
  MIPS: BCM47XX: Fix/improve Buffalo WHR-G54S support
  MIPS: OCTEON: program rx/tx-delay always from DT
  MIPS: OCTEON: delete board-specific link status
  MIPS: OCTEON: don't lie about interface type of CN3005 board
  MIPS: OCTEON: warn if deprecated link status is being used
  MIPS: OCTEON: add fixed-link nodes to in-kernel device tree
  MIPS: Delete unused flush_cache_sigtramp()
  ...
2019-03-05 11:28:25 -08:00
Linus Torvalds 736706bee3 get rid of legacy 'get_ds()' function
Every in-kernel use of this function defined it to KERNEL_DS (either as
an actual define, or as an inline function).  It's an entirely
historical artifact, and long long long ago used to actually read the
segment selector valueof '%ds' on x86.

Which in the kernel is always KERNEL_DS.

Inspired by a patch from Jann Horn that just did this for a very small
subset of users (the ones in fs/), along with Al who suggested a script.
I then just took it to the logical extreme and removed all the remaining
gunk.

Roughly scripted with

   git grep -l '(get_ds())' -- :^tools/ | xargs sed -i 's/(get_ds())/(KERNEL_DS)/'
   git grep -lw 'get_ds' -- :^tools/ | xargs sed -i '/^#define get_ds()/d'

plus manual fixups to remove a few unusual usage patterns, the couple of
inline function cases and to fix up a comment that had become stale.

The 'get_ds()' function remains in an x86 kvm selftest, since in user
space it actually does something relevant.

Inspired-by: Jann Horn <jannh@google.com>
Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-04 10:50:14 -08:00
Paul Burton c8790d657b
MIPS: MemoryMapID (MMID) Support
Introduce support for using MemoryMapIDs (MMIDs) as an alternative to
Address Space IDs (ASIDs). The major difference between the two is that
MMIDs are global - ie. an MMID uniquely identifies an address space
across all coherent CPUs. In contrast ASIDs are non-global per-CPU IDs,
wherein each address space is allocated a separate ASID for each CPU
upon which it is used. This global namespace allows a new GINVT
instruction be used to globally invalidate TLB entries associated with a
particular MMID across all coherent CPUs in the system, removing the
need for IPIs to invalidate entries with separate ASIDs on each CPU.

The allocation scheme used here is largely borrowed from arm64 (see
arch/arm64/mm/context.c). In essence we maintain a bitmap to track
available MMIDs, and MMIDs in active use at the time of a rollover to a
new MMID version are preserved in the new version. The allocation scheme
requires efficient 64 bit atomics in order to perform reasonably, so
this support depends upon CONFIG_GENERIC_ATOMIC64=n (ie. currently it
will only be included in MIPS64 kernels).

The first, and currently only, available CPU with support for MMIDs is
the MIPS I6500. This CPU supports 16 bit MMIDs, and so for now we cap
our MMIDs to 16 bits wide in order to prevent the bitmap growing to
absurd sizes if any future CPU does implement 32 bit MMIDs as the
architecture manuals suggest is recommended.

When MMIDs are in use we also make use of GINVT instruction which is
available due to the global nature of MMIDs. By executing a sequence of
GINVT & SYNC 0x14 instructions we can avoid the overhead of an IPI to
each remote CPU in many cases. One complication is that GINVT will
invalidate wired entries (in all cases apart from type 0, which targets
the entire TLB). In order to avoid GINVT invalidating any wired TLB
entries we set up, we make sure to create those entries using a reserved
MMID (0) that we never associate with any address space.

Also of note is that KVM will require further work in order to support
MMIDs & GINVT, since KVM is involved in allocating IDs for guests & in
configuring the MMU. That work is not part of this patch, so for now
when MMIDs are in use KVM is disabled.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
2019-02-04 10:56:41 -08:00
Linus Torvalds 89261c5702 Here's the main MIPS pull for Linux 4.21. Core architecture changes
include:
 
  - Syscall tables & definitions for unistd.h are now generated by
    scripts, providing greater consistency with other architectures &
    making it easier to add new syscalls.
 
  - Support for building kernels with no floating point support, upon
    which any userland attempting to use floating point instructions will
    receive a SIGILL. Mostly useful to shrink the kernel & as preparation
    for nanoMIPS support which does not yet include FP.
 
  - MIPS SIMD Architecture (MSA) vector register context is now exposed
    by ptrace via a new NT_MIPS_MSA regset.
 
  - ASIDs are now stored as 64b values even for MIPS32 kernels, expanding
    the ASID version field sufficiently that we don't need to worry about
    overflow & avoiding rare issues with reused ASIDs that have been
    observed in the wild.
 
  - The branch delay slot "emulation" page is now mapped without write
    permission for the user, preventing its use as a nice location for
    attacks to execute malicious code from.
 
  - Support for ioremap_prot(), primarily to allow gdb or other
    ptrace users the ability to view their tracee's memory using the same
    cache coherency attribute.
 
  - Optimizations to more cpu_has_* macros, allowing more to be
    compile-time constant where possible.
 
  - Enable building the whole kernel with UBSAN instrumentation.
 
  - Enable building the kernel with link-time dead code & data
    elimination.
 
 Platform specific changes include:
 
  - The Boston board gains a workaround for DMA prefetching issues with
    the EG20T Platform Controller Hub that it uses.
 
  - Cleanups to Cavium Octeon code removing about 20k lines of redundant
    code, mostly unused or duplicate register definitions in headers.
 
  - defconfig updates for the DECstation machines, including new
    defconfigs for r4k & 64b machines.
 
  - Further work on Loongson 3 support.
 
  - DMA fixes for SiByte machines.
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Merge tag 'mips_4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Paul Burton:
 "Here's the main MIPS pull for Linux 4.21. Core architecture changes
  include:

   - Syscall tables & definitions for unistd.h are now generated by
     scripts, providing greater consistency with other architectures &
     making it easier to add new syscalls.

   - Support for building kernels with no floating point support, upon
     which any userland attempting to use floating point instructions
     will receive a SIGILL. Mostly useful to shrink the kernel & as
     preparation for nanoMIPS support which does not yet include FP.

   - MIPS SIMD Architecture (MSA) vector register context is now exposed
     by ptrace via a new NT_MIPS_MSA regset.

   - ASIDs are now stored as 64b values even for MIPS32 kernels,
     expanding the ASID version field sufficiently that we don't need to
     worry about overflow & avoiding rare issues with reused ASIDs that
     have been observed in the wild.

   - The branch delay slot "emulation" page is now mapped without write
     permission for the user, preventing its use as a nice location for
     attacks to execute malicious code from.

   - Support for ioremap_prot(), primarily to allow gdb or other ptrace
     users the ability to view their tracee's memory using the same
     cache coherency attribute.

   - Optimizations to more cpu_has_* macros, allowing more to be
     compile-time constant where possible.

   - Enable building the whole kernel with UBSAN instrumentation.

   - Enable building the kernel with link-time dead code & data
     elimination.

  Platform specific changes include:

   - The Boston board gains a workaround for DMA prefetching issues with
     the EG20T Platform Controller Hub that it uses.

   - Cleanups to Cavium Octeon code removing about 20k lines of
     redundant code, mostly unused or duplicate register definitions in
     headers.

   - defconfig updates for the DECstation machines, including new
     defconfigs for r4k & 64b machines.

   - Further work on Loongson 3 support.

   - DMA fixes for SiByte machines"

* tag 'mips_4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (95 commits)
  MIPS: math-emu: Write-protect delay slot emulation pages
  MIPS: Remove struct mm_context_t fp_mode_switching field
  mips: generate uapi header and system call table files
  mips: add system call table generation support
  mips: remove syscall table entries
  mips: add +1 to __NR_syscalls in uapi header
  mips: rename scall64-64.S to scall64-n64.S
  mips: remove unused macros
  mips: add __NR_syscalls along with __NR_Linux_syscalls
  MIPS: Expand MIPS32 ASIDs to 64 bits
  MIPS: OCTEON: delete redundant register definitions
  MIPS: OCTEON: cvmx_gmxx_inf_mode: use oldest forward compatible definition
  MIPS: OCTEON: cvmx_mio_fus_dat3: use oldest forward compatible definition
  MIPS: OCTEON: cvmx_pko_mem_debug8: use oldest forward compatible definition
  MIPS: OCTEON: octeon-usb: use common gpio_bit definition
  MIPS: OCTEON: enable all OCTEON drivers in defconfig
  mips: annotate implicit fall throughs
  MIPS: Hardcode cpu_has_mips* where target ISA allows
  MIPS: MT: Remove norps command line parameter
  MIPS: Only include mmzone.h when CONFIG_NEED_MULTIPLE_NODES=y
  ...
2018-12-26 10:45:33 -08:00
Huacai Chen 25517ed4e9
MIPS: Let early memblock_alloc*() allocate memories bottom-up
After switched to NO_BOOTMEM, there are several boot failures. Some of
them have been fixed and some of them haven't. I find that many of them
are because of memory allocations are top-down, while the old behavior
is bottom-up. This patch let early memblock_alloc*() allocate memories
bottom-up to avoid some potential problems.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: bcec54bf31 ("mips: switch to NO_BOOTMEM")
Patchwork: https://patchwork.linux-mips.org/patch/21069/
References: https://patchwork.linux-mips.org/patch/21031/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <james.hogan@mips.com>
Cc: Steven J . Hill <Steven.Hill@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
2018-11-12 11:36:58 -08:00
Paul Burton b6d18e7704
MIPS: Don't dump Hi & Lo regs on >= MIPSr6
MIPSr6 removed the Hi & Lo registers, so displaying their values on
MIPSr6 systems is pointless. Avoid doing so.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21067/
Cc: linux-mips@linux-mips.org
2018-11-09 17:20:12 -08:00
Paul Burton 5328f7422e
MIPS: traps: Never enable FPU when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so we'll
never need to enable the FPU. Avoid doing so on a Co-Processor Unusable
exception (do_cpu), and remove the Floating Point Exception handler
(do_fpe) which should never be executed when the FPU is disabled.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21007/
Cc: linux-mips@linux-mips.org
2018-11-09 10:23:16 -08:00
Paul Burton 1975ed43ce
MIPS: Ensure emulated FP sets PF_USED_MATH
Emulated floating point instructions don't ensure that the PF_USED_MATH
flag is set for the task. This results in a couple of inconsistencies:

  - ptrace will return the default initial state of FP registers rather
    than the values actually stored in struct thread_struct, hiding
    state that has been updated by emulated floating point instructions.

  - If a task migrates to a CPU with an FPU after having emulated
    floating point instructions then its floating point register state
    will be reset to the default ~0 bit pattern, losing state from the
    emulated instructions.

Fix this by calling init_fp_ctx() from fpu_emulator_cop1Handler() to
consistently initialize FP state if it was previously uninitialized,
setting the PF_USED_MATH flag in the process.

All callers of fpu_emulator_cop1Handler() either call lose_fpu(1) before
it in order to save any live FPU registers to struct thread_struct, or
in the case of do_cpu() already know that the task does not own an FPU
so lose_fpu(1) would be a no-op. Since we know that saving FP context
will be unnecessary in the case where FP context was just initialized we
move this call into fpu_emulator_cop1Handler() too, providing
consistency & avoiding needless duplication.

Calls to own_fpu(1) are common after return from
fpu_emulator_cop1Handler() too, but this would not be a no-op in the
do_cpu() case so these are left as-is. A potential future improvement
could be to have fpu_emulator_cop1Handler() restore FPU state
automatically only if it saved it, though this may not be optimal if
some callers are better off without their current calls to own_fpu(1).
One potential example of this could be mipsr2_decoder() which as-is
could end up saving & restoring FP context repeatedly & unnecessarily if
emulating multiple FP instructions.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21003/
Cc: linux-mips@linux-mips.org
2018-11-09 10:23:14 -08:00
Paul Burton cc97ab235f
MIPS: Simplify FP context initialization
MIPS has up until now had 3 different ways for a task's floating point
context to be initialized:

  - If the task's first use of FP involves it gaining ownership of an
    FPU then _init_fpu() is used to initialize the FPU's registers such
    that they all contain ~0, and the FPU registers will be stored to
    struct thread_info later (eg. when context switching).

  - If the task first uses FP on a CPU without an associated FPU then
    fpu_emulator_init_fpu() initializes the task's floating point
    register state in struct thread_info such that all floating point
    register contain the bit pattern 0x7ff800007ff80000, different to
    the _init_fpu() behaviour.

  - If a task's floating point context is first accessed via ptrace then
    init_fp_ctx() initializes the floating point register state in
    struct thread_info to ~0, giving equivalent state to _init_fpu().

The _init_fpu() path has 2 separate implementations - one for r2k/r3k
style systems & one for r4k style systems. The _init_fpu() path also
requires that we be careful to clear & restore the value of the
Config5.FRE bit on modern systems in order to avoid inadvertently
triggering floating point exceptions.

None of this code is in a performance critical hot path - it runs only
the first time a task uses floating point. As such it doesn't seem to
warrant the complications of maintaining the _init_fpu() path.

Remove _init_fpu() & fpu_emulator_init_fpu(), instead using
init_fp_ctx() consistently to initialize floating point register state
in struct thread_info. Upon a task's first use of floating point this
will typically mean that we initialize state in memory & then load it
into FPU registers using _restore_fp() just as we would on a context
switch. For other paths such as __compute_return_epc_for_insn() or
mipsr2_decoder() this results in a significant simplification of the
work to be done.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21002/
Cc: linux-mips@linux-mips.org
2018-11-09 10:23:13 -08:00
Mike Rapoport 57c8a661d9 mm: remove include/linux/bootmem.h
Move remaining definitions and declarations from include/linux/bootmem.h
into include/linux/memblock.h and remove the redundant header.

The includes were replaced with the semantic patch below and then
semi-automated removal of duplicated '#include <linux/memblock.h>

@@
@@
- #include <linux/bootmem.h>
+ #include <linux/memblock.h>

[sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
[sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
[sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
  Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport 4fc4a09e4c memblock: replace __alloc_bootmem with memblock_alloc_from
The functions are equivalent, just the later does not require nobootmem
translation layer.

The conversion is done using the following semantic patch:

@@
expression size, align, goal;
@@
- __alloc_bootmem(size, align, goal)
+ memblock_alloc_from(size, align, goal)

Link: http://lkml.kernel.org/r/1536927045-23536-21-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport bcec54bf31
mips: switch to NO_BOOTMEM
MIPS already has memblock support and all the memory is already registered
with it.

This patch replaces bootmem memory reservations with memblock ones and
removes the bootmem initialization.

Since memblock allocates memory in top-down mode, we ensure that memblock
limit is max_low_pfn to prevent allocations from the high memory.

To have the exceptions base in the lower 512M of the physical memory, its
allocation in arch/mips/kernel/traps.c::traps_init() is using bottom-up
mode.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20560/
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
2018-09-14 12:37:28 -07:00
Paul Burton 4988154211
MIPS: Remove no-op/identity casts
Clean up instances of casts to the type that a value already has, since
they are effectively no-ops and only serve to complicate the code.

This is the result of the following semantic patch:

  @identitycast@
  type T;
  T *A;
  @@
  -	(T *)(A)
  +	A

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/19599/
2018-08-31 11:49:20 -07:00
Linus Torvalds 0c4b0f815f A few MIPS fixes for 4.19:
- Fix microMIPS build failures by adding a .insn directive to the
     barrier_before_unreachable() asm statement in order to convince the
     toolchain that the asm statement is a valid branch target rather
     than a bogus attempt to switch ISA.
 
   - Clean up our declarations of TLB functions that we overwrite with
     generated code in order to prevent the compiler making assumptions
     about alignment that cause microMIPS kernels built with GCC 7 &
     above to die early during boot.
 
   - Fix up a regression for MIPS32 kernels which slipped into the main
     MIPS pull for 4.19, causing CONFIG_32BIT=y kernels to contain
     inappropriate MIPS64 instructions.
 
   - Extend our existing workaround for MIPSr6 builds that end up using
     the __multi3 intrinsic to GCC 7 & below, rather than just GCC 7.
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Merge tag 'mips_4.19_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS fixes from Paul Burton:

  - Fix microMIPS build failures by adding a .insn directive to the
    barrier_before_unreachable() asm statement in order to convince the
    toolchain that the asm statement is a valid branch target rather
    than a bogus attempt to switch ISA.

  - Clean up our declarations of TLB functions that we overwrite with
    generated code in order to prevent the compiler making assumptions
    about alignment that cause microMIPS kernels built with GCC 7 &
    above to die early during boot.

  - Fix up a regression for MIPS32 kernels which slipped into the main
    MIPS pull for 4.19, causing CONFIG_32BIT=y kernels to contain
    inappropriate MIPS64 instructions.

  - Extend our existing workaround for MIPSr6 builds that end up using
    the __multi3 intrinsic to GCC 7 & below, rather than just GCC 7.

* tag 'mips_4.19_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: lib: Provide MIPS64r6 __multi3() for GCC < 7
  MIPS: Workaround GCC __builtin_unreachable reordering bug
  compiler.h: Allow arch-specific asm/compiler.h
  MIPS: Avoid move psuedo-instruction whilst using MIPS_ISA_LEVEL
  MIPS: Consistently declare TLB functions
  MIPS: Export tlbmiss_handler_setup_pgd near its definition
2018-08-23 14:23:08 -07:00
Linus Torvalds e5a32b5b21 Here are the main MIPS changes for 4.19.
An overview of the general architecture changes:
 
   - Massive DMA ops refactoring from Christoph Hellwig (huzzah for
     deleting crufty code!).
 
   - We introduce NT_MIPS_DSP & NT_MIPS_FP_MODE ELF notes & corresponding
     regsets to expose DSP ASE & floating point mode state respectively,
     both for live debugging & core dumps.
 
   - We better optimize our code by hard-coding cpu_has_* macros at
     compile time where their values are known due to the ISA revision
     that the kernel build is targeting.
 
   - The EJTAG exception handler now better handles SMP systems, where it
     was previously possible for CPUs to clobber a register value saved
     by another CPU.
 
   - Our implementation of memset() gained a couple of fixes for MIPSr6
     systems to return correct values in some cases where stores fault.
 
   - We now implement ioremap_wc() using the uncached-accelerated cache
     coherency attribute where supported, which is detected during boot,
     and fall back to plain uncached access where necessary. The
     MIPS-specific (and unused in tree) ioremap_uncached_accelerated() &
     ioremap_cacheable_cow() are removed.
 
   - The prctl(PR_SET_FP_MODE, ...) syscall is better supported for SMP
     systems by reworking the way we ensure remote CPUs that may be
     running threads within the affected process switch mode.
 
   - Systems using the MIPS Coherence Manager will now set the
     MIPS_IC_SNOOPS_REMOTE flag to avoid some unnecessary cache
     maintenance overhead when flushing the icache.
 
   - A few fixes were made for building with clang/LLVM, which
     now sucessfully builds kernels for many of our platforms.
 
   - Miscellaneous cleanups all over.
 
 And some platform-specific changes:
 
   - ar7 gained stubs for a few clock API functions to fix build failures
     for some drivers.
 
   - ath79 gained support for a few new SoCs, a few fixes & better
     gpio-keys support.
 
   - Ci20 now exposes its SPI bus using the spi-gpio driver.
 
   - The generic platform can now auto-detect a suitable value for
     PHYS_OFFSET based upon the memory map described by the device tree,
     allowing us to avoid wasting memory on page book-keeping for systems
     where RAM starts at a non-zero physical address.
 
   - Ingenic systems using the jz4740 platform code now link their
     vmlinuz higher to allow for kernels of a realistic size.
 
   - Loongson32 now builds the kernel targeting MIPSr1 rather than MIPSr2
     to avoid CPU errata.
 
   - Loongson64 gains a couple of fixes, a workaround for a write
     buffering issue & support for the Loongson 3A R3.1 CPU.
 
   - Malta now uses the piix4-poweroff driver to handle powering down.
 
   - Microsemi Ocelot gained support for its SPI bus & NOR flash, its
     second MDIO bus and can now be supported by a FIT/.itb image.
 
   - Octeon saw a bunch of header cleanups which remove a lot of
     duplicate or unused code.
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Merge tag 'mips_4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Paul Burton:
 "Here are the main MIPS changes for 4.19.

  An overview of the general architecture changes:

   - Massive DMA ops refactoring from Christoph Hellwig (huzzah for
     deleting crufty code!).

   - We introduce NT_MIPS_DSP & NT_MIPS_FP_MODE ELF notes &
     corresponding regsets to expose DSP ASE & floating point mode state
     respectively, both for live debugging & core dumps.

   - We better optimize our code by hard-coding cpu_has_* macros at
     compile time where their values are known due to the ISA revision
     that the kernel build is targeting.

   - The EJTAG exception handler now better handles SMP systems, where
     it was previously possible for CPUs to clobber a register value
     saved by another CPU.

   - Our implementation of memset() gained a couple of fixes for MIPSr6
     systems to return correct values in some cases where stores fault.

   - We now implement ioremap_wc() using the uncached-accelerated cache
     coherency attribute where supported, which is detected during boot,
     and fall back to plain uncached access where necessary. The
     MIPS-specific (and unused in tree) ioremap_uncached_accelerated() &
     ioremap_cacheable_cow() are removed.

   - The prctl(PR_SET_FP_MODE, ...) syscall is better supported for SMP
     systems by reworking the way we ensure remote CPUs that may be
     running threads within the affected process switch mode.

   - Systems using the MIPS Coherence Manager will now set the
     MIPS_IC_SNOOPS_REMOTE flag to avoid some unnecessary cache
     maintenance overhead when flushing the icache.

   - A few fixes were made for building with clang/LLVM, which now
     sucessfully builds kernels for many of our platforms.

   - Miscellaneous cleanups all over.

  And some platform-specific changes:

   - ar7 gained stubs for a few clock API functions to fix build
     failures for some drivers.

   - ath79 gained support for a few new SoCs, a few fixes & better
     gpio-keys support.

   - Ci20 now exposes its SPI bus using the spi-gpio driver.

   - The generic platform can now auto-detect a suitable value for
     PHYS_OFFSET based upon the memory map described by the device tree,
     allowing us to avoid wasting memory on page book-keeping for
     systems where RAM starts at a non-zero physical address.

   - Ingenic systems using the jz4740 platform code now link their
     vmlinuz higher to allow for kernels of a realistic size.

   - Loongson32 now builds the kernel targeting MIPSr1 rather than
     MIPSr2 to avoid CPU errata.

   - Loongson64 gains a couple of fixes, a workaround for a write
     buffering issue & support for the Loongson 3A R3.1 CPU.

   - Malta now uses the piix4-poweroff driver to handle powering down.

   - Microsemi Ocelot gained support for its SPI bus & NOR flash, its
     second MDIO bus and can now be supported by a FIT/.itb image.

   - Octeon saw a bunch of header cleanups which remove a lot of
     duplicate or unused code"

* tag 'mips_4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (123 commits)
  MIPS: Remove remnants of UASM_ISA
  MIPS: netlogic: xlr: Remove erroneous check in nlm_fmn_send()
  MIPS: VDSO: Force link endianness
  MIPS: Always specify -EB or -EL when using clang
  MIPS: Use dins to simplify __write_64bit_c0_split()
  MIPS: Use read-write output operand in __write_64bit_c0_split()
  MIPS: Avoid using array as parameter to write_c0_kpgd()
  MIPS: vdso: Allow clang's --target flag in VDSO cflags
  MIPS: genvdso: Remove GOT checks
  MIPS: Remove obsolete MIPS checks for DST node "chosen@0"
  MIPS: generic: Remove input symbols from defconfig
  MIPS: Delete unused code in linux32.c
  MIPS: Remove unused sys_32_mmap2
  MIPS: Remove nabi_no_regargs
  mips: dts: mscc: enable spi and NOR flash support on ocelot PCB123
  mips: dts: mscc: Add spi on Ocelot
  MIPS: Loongson: Merge load addresses
  MIPS: Loongson: Set Loongson32 to MIPS32R1
  MIPS: mscc: ocelot: add interrupt controller properties to GPIO controller
  MIPS: generic: Select MIPS_AUTO_PFN_OFFSET
  ...
2018-08-13 19:24:32 -07:00
Paul Burton 4bcb4ad663
MIPS: Consistently declare TLB functions
Since at least the beginning of the git era we've declared our TLB
exception handling functions inconsistently. They're actually functions,
but we declare them as arrays of u32 where each u32 is an encoded
instruction. This has always been the case for arch/mips/mm/tlbex.c, and
has also been true for arch/mips/kernel/traps.c since commit
86a1708a9d ("MIPS: Make tlb exception handler definitions and
declarations match.") which aimed for consistency but did so by
consistently making the our C code inconsistent with our assembly.

This is all usually harmless, but when using GCC 7 or newer to build a
kernel targeting microMIPS (ie. CONFIG_CPU_MICROMIPS=y) it becomes
problematic. With microMIPS bit 0 of the program counter indicates the
ISA mode. When bit 0 is zero instructions are decoded using the standard
MIPS32 or MIPS64 ISA. When bit 0 is one instructions are decoded using
microMIPS. This means that function pointers become odd - their least
significant bit is one for microMIPS code. We work around this in cases
where we need to access code using loads & stores with our
msk_isa16_mode() macro which simply clears bit 0 of the value it is
given:

  #define msk_isa16_mode(x) ((x) & ~0x1)

For example we do this for our TLB load handler in
build_r4000_tlb_load_handler():

  u32 *p = (u32 *)msk_isa16_mode((ulong)handle_tlbl);

We then write code to p, expecting it to be suitably aligned (our LEAF
macro aligns functions on 4 byte boundaries, so (ulong)handle_tlbl will
give a value one greater than a multiple of 4 - ie. the start of a
function on a 4 byte boundary, with the ISA mode bit 0 set).

This worked fine up to GCC 6, but GCC 7 & onwards is smart enough to
presume that handle_tlbl which we declared as an array of u32s must be
aligned sufficiently that bit 0 of its address will never be set, and as
a result optimize out msk_isa16_mode(). This leads to p having an
address with bit 0 set, and when we go on to attempt to store code at
that address we take an address error exception due to the unaligned
memory access.

This leads to an exception prior to the kernel having configured its own
exception handlers, so we jump to whatever handlers the bootloader
configured. In the case of QEMU this results in a silent hang, since it
has no useful general exception vector.

Fix this by consistently declaring our TLB-related functions as
functions. For handle_tlbl(), handle_tlbs() & handle_tlbm() we do this
in asm/tlbex.h & we make use of the existing declaration of
tlbmiss_handler_setup_pgd() in asm/mmu_context.h. Our TLB handler
generation code in arch/mips/mm/tlbex.c is adjusted to deal with these
definitions, in most cases simply by casting the function pointers to
u32 pointers.

This allows us to include asm/mmu_context.h in arch/mips/mm/tlbex.c to
get the definitions of tlbmiss_handler_setup_pgd & pgd_current, removing
some needless duplication. Consistently using msk_isa16_mode() on
function pointers means we no longer need the
tlbmiss_handler_setup_pgd_start symbol so that is removed entirely.

Now that we're declaring our functions as functions GCC stops optimizing
out msk_isa16_mode() & a microMIPS kernel built with either GCC 7.3.0 or
8.1.0 boots successfully.

Signed-off-by: Paul Burton <paul.burton@mips.com>
2018-08-10 17:27:53 -07:00
Paul Burton 5a267832c2
MIPS: Call dump_stack() from show_regs()
The generic nmi_cpu_backtrace() function calls show_regs() when a struct
pt_regs is available, and dump_stack() otherwise. If we were to make use
of the generic nmi_cpu_backtrace() with MIPS' current implementation of
show_regs() this would mean that we see only register data with no
accompanying stack information, in contrast with our current
implementation which calls dump_stack() regardless of whether register
state is available.

In preparation for making use of the generic nmi_cpu_backtrace() to
implement arch_trigger_cpumask_backtrace(), have our implementation of
show_regs() call dump_stack() and drop the explicit dump_stack() call in
arch_dump_stack() which is invoked by arch_trigger_cpumask_backtrace().

This will allow the output we produce to remain the same after a later
patch switches to using nmi_cpu_backtrace(). It may mean that we produce
extra stack output in other uses of show_regs(), but this:

  1) Seems harmless.
  2) Is good for consistency between arch_trigger_cpumask_backtrace()
     and other users of show_regs().
  3) Matches the behaviour of the ARM & PowerPC architectures.

Marked for stable back to v4.9 as a prerequisite of the following patch
"MIPS: Call dump_stack() from show_regs()".

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/19596/
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # v4.9+
2018-06-28 11:48:54 -07:00
Paul Burton 8c8d953c28
MIPS: Schedule on CPUs we need to lose FPU for a mode switch
Commit 6b8322576e ("MIPS: Force CPUs to lose FP context during mode
switches") ensures that we react to PR_SET_FP_MODE prctl syscalls
quickly by broadcasting an IPI in order to cause CPUs to lose FPU access
when necessary. Whilst it achieves that, unfortunately it causes all
sorts of strange race conditions because:

 1) The IPI may arrive at a point where the FPU is in the process of
    being enabled, but that process is not yet complete leading to a
    state we aren't prepared to handle. For example:

    [  370.215903] do_cpu invoked from kernel context![#1]:
    [  370.221064] CPU: 0 PID: 963 Comm: fp-prctl Not tainted 4.9.0-rc5-00323-g210db32-dirty #226
    [  370.229420] task: a8000000fd672e00 task.stack: a8000000fd630000
    [  370.235399] $ 0   : 0000000000000000 0000000000000001 0000000000000001 a8000000fd630000
    [  370.243882] $ 4   : a8000000fd672e00 0000000000000000 0000000000000453 0000000000000000
    [  370.252317] $ 8   : 0000000000000000 a8000000fd637c28 1000000000000000 0000000000000010
    [  370.260753] $12   : 00000000140084e0 ffffffff80109c00 0000000000000000 0000000000000002
    [  370.269179] $16   : ffffffff8092f080 a8000000fd672e00 ffffffff80107fe8 a8000000fd485000
    [  370.277612] $20   : ffffffff8084d328 ffffffff80940000 0000000000000009 ffffffff80930000
    [  370.286038] $24   : 0000000000000000 900000001612048c
    [  370.294476] $28   : a8000000fd630000 a8000000fd637ac0 ffffffff80937300 ffffffff8010807c
    [  370.302909] Hi    : 0000000000000000
    [  370.306595] Lo    : 0000000000000200
    [  370.310376] epc   : ffffffff80115d38 _save_fp+0x10/0xa0
    [  370.315784] ra    : ffffffff8010807c prepare_for_fp_mode_switch+0x94/0x1b0
    [  370.322707] Status: 140084e2 KX SX UX KERNEL EXL
    [  370.327980] Cause : 1080002c (ExcCode 0b)
    [  370.332091] PrId  : 0001a428 (MIPS P6600)
    [  370.336179] Modules linked in:
    [  370.339486] Process fp-prctl (pid: 963, threadinfo=a8000000fd630000, task=a8000000fd672e00, tls=00000000756e67d0)
    [  370.349724] Stack : 0000000000000000 a8000000fd557dc0 0000000000000000 ffffffff801ca8e0
    [  370.358161]         0000000000000000 a8000000fd637b9c 0000000000000009 ffffffff80923780
    [  370.366575]         ffffffff80850000 ffffffff8011610c 00000000000000b8 ffffffff801a5084
    [  370.374989]         ffffffff8084a370 ffffffff8084a388 ffffffff80923780 ffffffff80923828
    [  370.383395]         0000000000010000 ffffffff809237a8 0000000000020000 ffffffff80a40000
    [  370.391817]         000000000000007c 00000000004a0000 00000000756dedd0 ffffffff801a5188
    [  370.400230]         a800000002014900 0000000000000001 ffffffff80923780 0000000080923828
    [  370.408644]         ffffffff80923780 ffffffff80923780 ffffffff80923828 ffffffff801a521c
    [  370.417066]         ffffffff80923780 ffffffff80923828 0000000000010000 ffffffff801a8f84
    [  370.425472]         ffffffff80a40000 a8000000fd637c20 ffffffff80a39240 0000000000000001
    [  370.433885]         ...
    [  370.436562] Call Trace:
    [  370.439222] [<ffffffff80115d38>] _save_fp+0x10/0xa0
    [  370.444305] [<ffffffff8010807c>] prepare_for_fp_mode_switch+0x94/0x1b0
    [  370.451035] [<ffffffff801ca8e0>] flush_smp_call_function_queue+0xf8/0x230
    [  370.457991] [<ffffffff8011610c>] ipi_call_interrupt+0xc/0x20
    [  370.463814] [<ffffffff801a5084>] __handle_irq_event_percpu+0xc4/0x1a8
    [  370.470404] [<ffffffff801a5188>] handle_irq_event_percpu+0x20/0x68
    [  370.476734] [<ffffffff801a521c>] handle_irq_event+0x4c/0x88
    [  370.482486] [<ffffffff801a8f84>] handle_edge_irq+0x12c/0x210
    [  370.488316] [<ffffffff801a47a0>] generic_handle_irq+0x38/0x48
    [  370.494280] [<ffffffff804a2dbc>] gic_handle_shared_int+0x194/0x268
    [  370.500616] [<ffffffff801a47a0>] generic_handle_irq+0x38/0x48
    [  370.506529] [<ffffffff80107e60>] do_IRQ+0x18/0x28
    [  370.511445] [<ffffffff804a1524>] plat_irq_dispatch+0xc4/0x140
    [  370.517339] [<ffffffff80106230>] ret_from_irq+0x0/0x4
    [  370.522583] [<ffffffff8010fad4>] do_ri+0x4fc/0x7e8
    [  370.527546] [<ffffffff80106220>] ret_from_exception+0x0/0x10

 2) The IPI may arrive during kernel use of the FPU, since we generally
    only disable preemption around use of the FPU & leave interrupts
    enabled. This can lead to us unexpectedly losing access to the FPU
    in places where it previously had not been possible. For example:

    do_cpu invoked from kernel context![#2]:
    CPU: 2 PID: 7338 Comm: fp-prctl Tainted: G      D         4.7.0-00424-g49b0c82
    #2
    task: 838e4000 ti: 88d38000 task.ti: 88d38000
    $ 0   : 00000000 00000001 ffffffff 88d3fef8
    $ 4   : 838e4000 88d38004 00000000 00000001
    $ 8   : 3400fc01 801f8020 808e9100 24000000
    $12   : dbffffff 807b69d8 807b0000 00000000
    $16   : 00000000 80786150 00400fc4 809c0398
    $20   : 809c0338 0040273c 88d3ff28 808e9d30
    $24   : 808e9d30 00400fb4
    $28   : 88d38000 88d3fe88 00000000 8011a2ac
    Hi    : 0040273c
    Lo    : 88d3ff28
    epc   : 80114178 _restore_fp+0x10/0xa0
    ra    : 8011a2ac mipsr2_decoder+0xd5c/0x1660
    Status: 1400fc03    KERNEL EXL IE
    Cause : 1080002c (ExcCode 0b)
    PrId  : 0001a920 (MIPS I6400)
    Modules linked in:
    Process fp-prctl (pid: 7338, threadinfo=88d38000, task=838e4000, tls=766527d0)
    Stack : 00000000 00000000 00000000 88d3fe98 00000000 00000000 809c0398 809c0338
          808e9100 00000000 88d3ff28 00400fc4 00400fc4 0040273c 7fb69e18 004a0000
          004a0000 004a0000 7664add0 8010de18 00000000 00000000 88d3fef8 88d3ff28
          808e9100 00000000 766527d0 8010e534 000c0000 85755000 8181d580 00000000
          00000000 00000000 004a0000 00000000 766527d0 7fb69e18 004a0000 80105c20
          ...
    Call Trace:
    [<80114178>] _restore_fp+0x10/0xa0
    [<8011a2ac>] mipsr2_decoder+0xd5c/0x1660
    [<8010de18>] do_ri+0x90/0x6b8
    [<80105c20>] ret_from_exception+0x0/0x10

At first glance a simple fix may seem to be to disable interrupts around
kernel use of the FPU rather than merely preemption, however this would
introduce further overhead outside of the mode switch path & doesn't
solve the third problem:

 3) The IPI may arrive whilst the kernel is running code that will lead
    to a preempt_disable() call & FPU usage soon. If this happens then
    the IPI will be serviced & we'll proceed to enable an FPU whilst the
    mode switch is in progress, leading to strange & inconsistent
    behaviour.

Further to all of this is a separate but related problem:

 4) There are various paths through which we may enable the FPU without
    the user having triggered a coprocessor 1 disabled exception. These
    paths are those in which we emulate instructions & then enable the
    FPU with the expectation that the user might execute an FP
    instruction shortly afterwards. However these paths have not
    previously checked whether an FP mode switch is underway for the
    task, and therefore could enable the FPU whilst such a mode switch
    is in progress leading to strange & inconsistent behaviour for user
    code.

This patch fixes all of the above by taking a step back & re-examining
our approach to FP mode switches. Up until now we have taken these basic
steps:

 a) Prevent any threads that are part of the affected process from being
    able to obtain ownership of the FPU.

 b) Cause any threads that are part of the affected process and already
    have ownership of an FPU to lose it.

 c) Set the thread flags for each thread that is part of the affected
    process to reflect the new FP mode.

 d) Allow threads to obtain ownership of the FPU again.

This approach is however more complex than necessary. All that we really
require is that the mode switch has occurred for all threads that are
part of the affected process before mips_set_process_fp_mode(), and thus
the PR_SET_FP_MODE prctl() syscall, returns. This doesn't require that
we stop threads from owning or using an FPU whilst a mode switch occurs,
only that we force them to relinquish it after the mode switch has
occurred such that they next own an FPU with the correct mode
configured. Our basic steps therefore simplify to:

 A) Set the thread flags for each thread that is part of the affected
    process to reflect the new FP mode.

 B) Cause any threads that are part of the affected process and already
    have ownership of an FPU to lose it.

We implement B) by forcing each CPU which might be running a thread
which is part of the affected process to schedule a no-op function,
which causes the affected thread to lose its FPU ownership when it is
descheduled.

The end result is simpler FP mode switching with less overhead in the
FPU enable path (ie. enable_restore_fp_context()) and fewer moving
parts.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 9791554b45 ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS")
Fixes: 6b8322576e ("MIPS: Force CPUs to lose FP context during mode switches")
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v4.0+
2018-06-24 09:27:27 -07:00
Guenter Roeck 0bb0a1149e signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions
Most mips builds fail with

arch/mips/kernel/traps.c: In function ‘force_fcr31_sig’:
arch/mips/kernel/traps.c:732:2: error:
	‘si_code’ may be used uninitialized in this function

Fix the problem by initializing si_code with FPE_FLTUNK (undiagnosed
floating point exception).

Fixes: f43a54a0d9 ("signal/mips: Use force_sig_fault where appropriate")
Cc: linux-mips@linux-mips.org
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2018-05-16 19:21:41 -05:00
Eric W. Biederman f43a54a0d9 signal/mips: Use force_sig_fault where appropriate
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.

Simplify this process by using the helper force_sig_fault.  Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.

In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.

Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:41:02 -05:00
Peter Zijlstra 6887a56b6e sched/wait, arch/mips: Fix and convert wait_on_atomic_t() usage to the new wait_var_event() API
The old wait_on_atomic_t() is going to get removed, use the more
flexible wait_var_event() API instead.

And while there, fix a bug and add the missing wakeup...

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-20 08:23:23 +01:00
Eric W. Biederman 5f74972ce6 signal: Don't use structure initializers for struct siginfo
The siginfo structure has all manners of holes with the result that a
structure initializer is not guaranteed to initialize all of the bits.
As we have to copy the structure to userspace don't even try to use
a structure initializer.  Instead use clear_siginfo followed by initializing
selected fields.  This gives a guarantee that uninitialized kernel memory
is not copied to userspace.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-22 19:07:08 -06:00
David Howells 5e4def2038 Pass mode to wait_on_atomic_t() action funcs and provide default actions
Make wait_on_atomic_t() pass the TASK_* mode onto its action function as an
extra argument and make it 'unsigned int throughout.

Also, consolidate a bunch of identical action functions into a default
function that can do the appropriate thing for the mode.

Also, change the argument name in the bit_wait*() function declarations to
reflect the fact that it's the mode and not the bit number.

[Peter Z gives this a grudging ACK, but thinks that the whole atomic_t wait
should be done differently, though he's not immediately sure as to how]

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
cc: Ingo Molnar <mingo@kernel.org>
2017-11-13 15:38:16 +00:00
Paul Burton e83f7e02af MIPS: CPS: Have asm/mips-cps.h include CM & CPC headers
With Coherence Manager (CM) 3.5 information about the topology of the
system, which has previously only been available through & accessed from
the CM, is now also provided by the Cluster Power Controller (CPC). This
includes a new CPC_CONFIG register mirroring GCR_CONFIG, and similarly a
new CPC_Cx_CONFIG register mirroring GCR_Cx_CONFIG.

In preparation for adjusting functions such as mips_cm_numcores(), which
have previously only needed to access the CM, to also access the CPC
this patch modifies the way we use the various CPS headers. Rather than
having users include asm/mips-cm.h or asm/mips-cpc.h individually we
instead have users include asm/mips-cps.h which in turn includes
asm/mips-cm.h & asm/mips-cpc.h. This means that users will gain access
to both CM & CPC registers by including one header, and most importantly
it makes asm/mips-cps.h an ideal location for helper functions which
need to access the various components of the CPS.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17015/
Patchwork: https://patchwork.linux-mips.org/patch/17217/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30 00:57:27 +02:00
Paul Burton 93c5bba575 MIPS: CM: Use BIT/GENMASK for register fields, order & drop shifts
There's no reason for us not to use BIT() & GENMASK() in asm/mips-cm.h
when declaring macros corresponding to register fields. This patch
modifies our definitions to do so.

The *_SHF definitions are removed entirely - they duplicate information
found in the masks, are infrequently used & can be replaced with use of
__ffs() where needed.

The *_MSK definitions then lose their _MSK suffix which is now somewhat
redundant, and users are modified to match.

The field definitions are moved to follow the appropriate register's
accessor functions, which helps to keep the field definitions in order &
to find the appropriate fields for a given register. Whilst here a
comment is added describing each register & including its name, which is
helpful both for linking the register back to hardware documentation &
for grepping purposes.

This also cleans up a couple of issues that became obvious as a result
of making the changes described above:

  - We previously had definitions for GCR_Cx_RESET_EXT_BASE & a phony
    copy of that named GCR_RESET_EXT_BASE - a register which does not
    exist. The bad definitions were added by commit 497e803ebf ("MIPS:
    smp-cps: Ensure secondary cores start with EVA disabled") and made
    use of from boot_core(), which is now modified to use the
    GCR_Cx_RESET_EXT_BASE definitions.

  - We had a typo in CM_GCR_ERROR_CAUSE_ERRINGO_MSK - we now correctly
    define this as inFo rather than inGo.

Now that we don't duplicate field information between _SHF & _MSK
definitions, and keep the fields next to the register accessors, it will
be much easier to spot & prevent any similar oddities being introduced
in the future.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17001/
Patchwork: https://patchwork.linux-mips.org/patch/17216/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29 15:21:57 +02:00
Ralf Baechle b123718b10 MIPS: signal: Remove unreachable code from force_fcr31_sig().
Based on discussion with Linus remove the impossible to reach code
rather than replacing it with a BUG().

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Link: http://lkml.kernel.org/r/20170718140651.15973-4-ebiederm@xmission.com
2017-08-29 15:21:52 +02:00
Paul Burton 3b2db173f0 MIPS: Remove unused R6000 support
The kernel contains a small amount of incomplete code aimed at
supporting old R6000 CPUs. This is:

  - Unused, as no machine selects CONFIG_SYS_HAS_CPU_R6000.

  - Broken, since there are glaring errors such as r6000_fpu.S moving
    the FCSR register to t1, then ignoring it & instead saving t0 into
    struct sigcontext...

  - A maintenance headache, since it's code that nobody can test which
    nevertheless imposes constraints on code which it shares with other
    machines.

Remove this incomplete & broken R6000 CPU support in order to clean up
and in preparation for changes which will no longer need to consider
dragging the pretense of R6000 support along with them.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16236/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29 15:21:51 +02:00
Thomas Meyer a94c33dd1f lib/extable.c: use bsearch() library function in search_extable()
[thomas@m3y3r.de: v3: fix arch specific implementations]
  Link: http://lkml.kernel.org/r/1497890858.12931.7.camel@m3y3r.de
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-10 16:32:35 -07:00
James Hogan 8542363633 MIPS: Avoid accidental raw backtrace
Since commit 81a76d7119 ("MIPS: Avoid using unwind_stack() with
usermode") show_backtrace() invokes the raw backtracer when
cp0_status & ST0_KSU indicates user mode to fix issues on EVA kernels
where user and kernel address spaces overlap.

However this is used by show_stack() which creates its own pt_regs on
the stack and leaves cp0_status uninitialised in most of the code paths.
This results in the non deterministic use of the raw back tracer
depending on the previous stack content.

show_stack() deals exclusively with kernel mode stacks anyway, so
explicitly initialise regs.cp0_status to KSU_KERNEL (i.e. 0) to ensure
we get a useful backtrace.

Fixes: 81a76d7119 ("MIPS: Avoid using unwind_stack() with usermode")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15+
Patchwork: https://patchwork.linux-mips.org/patch/16656/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-06-30 04:42:15 +02:00
Kees Cook 063246641d format-security: move static strings to const
While examining output from trial builds with -Wformat-security enabled,
many strings were found that should be defined as "const", or as a char
array instead of char pointer.  This makes some static analysis easier,
by producing fewer false positives.

As these are all trivial changes, it seemed best to put them all in a
single patch rather than chopping them up per maintainer.

Link: http://lkml.kernel.org/r/20170405214711.GA5711@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Jes Sorensen <jes@trained-monkey.org>	[runner.c]
Cc: Tony Lindgren <tony@atomide.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Yisen Zhuang <yisen.zhuang@huawei.com>
Cc: Salil Mehta <salil.mehta@huawei.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Mugunthan V N <mugunthanvnm@ti.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Antonio Quartulli <a@unstable.cc>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Kejian Yan <yankejian@huawei.com>
Cc: Daode Huang <huangdaode@hisilicon.com>
Cc: Qianqian Xie <xieqianqian@huawei.com>
Cc: Philippe Reynes <tremyfr@gmail.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Christian Gromm <christian.gromm@microchip.com>
Cc: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Cc: Jason Litzinger <jlitzingerdev@gmail.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:14 -07:00
Huacai Chen 5a34133167 MIPS: Check TLB before handle_ri_rdhwr() for Loongson-3
Loongson-3's micro TLB (ITLB) is not strictly a subset of JTLB. That
means: when a JTLB entry is replaced by hardware, there may be an old
valid entry exists in ITLB. So, a TLB miss exception may occur while
handle_ri_rdhwr() is running because it try to access EPC's content.
However, handle_ri_rdhwr() doesn't clear EXL, which makes a TLB Refill
exception be treated as a TLB Invalid exception and tlbp may fail. In
this case, if FTLB (which is usually set-associative instead of set-
associative) is enabled, a tlbp failure will cause an invalid tlbwi,
which will hang the whole system.

This patch rename handle_ri_rdhwr_vivt to handle_ri_rdhwr_tlbp and use
it for Loongson-3. It try to solve the same problem described as below,
but more straightforwards.

https://patchwork.linux-mips.org/patch/12591/

I think Loongson-2 has the same problem, but it has no FTLB, so we just
keep it as is.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Rui Wang <wangr@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J . Hill <Steven.Hill@caviumnetworks.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15753/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-03-21 21:52:54 +01:00
Ingo Molnar 68e21be291 sched/headers: Move task->mm handling methods to <linux/sched/mm.h>
Move the following task->mm helper APIs into a new header file,
<linux/sched/mm.h>, to further reduce the size and complexity
of <linux/sched.h>.

Here are how the APIs are used in various kernel files:

  # mm_alloc():
  arch/arm/mach-rpc/ecard.c
  fs/exec.c
  include/linux/sched/mm.h
  kernel/fork.c

  # __mmdrop():
  arch/arc/include/asm/mmu_context.h
  include/linux/sched/mm.h
  kernel/fork.c

  # mmdrop():
  arch/arm/mach-rpc/ecard.c
  arch/m68k/sun3/mmu_emu.c
  arch/x86/mm/tlb.c
  drivers/gpu/drm/amd/amdkfd/kfd_process.c
  drivers/gpu/drm/i915/i915_gem_userptr.c
  drivers/infiniband/hw/hfi1/file_ops.c
  drivers/vfio/vfio_iommu_spapr_tce.c
  fs/exec.c
  fs/proc/base.c
  fs/proc/task_mmu.c
  fs/proc/task_nommu.c
  fs/userfaultfd.c
  include/linux/mmu_notifier.h
  include/linux/sched/mm.h
  kernel/fork.c
  kernel/futex.c
  kernel/sched/core.c
  mm/khugepaged.c
  mm/ksm.c
  mm/mmu_context.c
  mm/mmu_notifier.c
  mm/oom_kill.c
  virt/kvm/kvm_main.c

  # mmdrop_async_fn():
  include/linux/sched/mm.h

  # mmdrop_async():
  include/linux/sched/mm.h
  kernel/fork.c

  # mmget_not_zero():
  fs/userfaultfd.c
  include/linux/sched/mm.h
  mm/oom_kill.c

  # mmput():
  arch/arc/include/asm/mmu_context.h
  arch/arc/kernel/troubleshoot.c
  arch/frv/mm/mmu-context.c
  arch/powerpc/platforms/cell/spufs/context.c
  arch/sparc/include/asm/mmu_context_32.h
  drivers/android/binder.c
  drivers/gpu/drm/etnaviv/etnaviv_gem.c
  drivers/gpu/drm/i915/i915_gem_userptr.c
  drivers/infiniband/core/umem.c
  drivers/infiniband/core/umem_odp.c
  drivers/infiniband/core/uverbs_main.c
  drivers/infiniband/hw/mlx4/main.c
  drivers/infiniband/hw/mlx5/main.c
  drivers/infiniband/hw/usnic/usnic_uiom.c
  drivers/iommu/amd_iommu_v2.c
  drivers/iommu/intel-svm.c
  drivers/lguest/lguest_user.c
  drivers/misc/cxl/fault.c
  drivers/misc/mic/scif/scif_rma.c
  drivers/oprofile/buffer_sync.c
  drivers/vfio/vfio_iommu_type1.c
  drivers/vhost/vhost.c
  drivers/xen/gntdev.c
  fs/exec.c
  fs/proc/array.c
  fs/proc/base.c
  fs/proc/task_mmu.c
  fs/proc/task_nommu.c
  fs/userfaultfd.c
  include/linux/sched/mm.h
  kernel/cpuset.c
  kernel/events/core.c
  kernel/events/uprobes.c
  kernel/exit.c
  kernel/fork.c
  kernel/ptrace.c
  kernel/sys.c
  kernel/trace/trace_output.c
  kernel/tsacct.c
  mm/memcontrol.c
  mm/memory.c
  mm/mempolicy.c
  mm/migrate.c
  mm/mmu_notifier.c
  mm/nommu.c
  mm/oom_kill.c
  mm/process_vm_access.c
  mm/rmap.c
  mm/swapfile.c
  mm/util.c
  virt/kvm/async_pf.c

  # mmput_async():
  include/linux/sched/mm.h
  kernel/fork.c
  mm/oom_kill.c

  # get_task_mm():
  arch/arc/kernel/troubleshoot.c
  arch/powerpc/platforms/cell/spufs/context.c
  drivers/android/binder.c
  drivers/gpu/drm/etnaviv/etnaviv_gem.c
  drivers/infiniband/core/umem.c
  drivers/infiniband/core/umem_odp.c
  drivers/infiniband/hw/mlx4/main.c
  drivers/infiniband/hw/mlx5/main.c
  drivers/infiniband/hw/usnic/usnic_uiom.c
  drivers/iommu/amd_iommu_v2.c
  drivers/iommu/intel-svm.c
  drivers/lguest/lguest_user.c
  drivers/misc/cxl/fault.c
  drivers/misc/mic/scif/scif_rma.c
  drivers/oprofile/buffer_sync.c
  drivers/vfio/vfio_iommu_type1.c
  drivers/vhost/vhost.c
  drivers/xen/gntdev.c
  fs/proc/array.c
  fs/proc/base.c
  fs/proc/task_mmu.c
  include/linux/sched/mm.h
  kernel/cpuset.c
  kernel/events/core.c
  kernel/exit.c
  kernel/fork.c
  kernel/ptrace.c
  kernel/sys.c
  kernel/trace/trace_output.c
  kernel/tsacct.c
  mm/memcontrol.c
  mm/memory.c
  mm/mempolicy.c
  mm/migrate.c
  mm/mmu_notifier.c
  mm/nommu.c
  mm/util.c

  # mm_access():
  fs/proc/base.c
  include/linux/sched/mm.h
  kernel/fork.c
  mm/process_vm_access.c

  # mm_release():
  arch/arc/include/asm/mmu_context.h
  fs/exec.c
  include/linux/sched/mm.h
  include/uapi/linux/sched.h
  kernel/exit.c
  kernel/fork.c

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-03 01:43:28 +01:00
Ingo Molnar b17b01533b sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/debug.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:34 +01:00
Vegard Nossum f1f1007644 mm: add new mmgrab() helper
Apart from adding the helper function itself, the rest of the kernel is
converted mechanically using:

  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/'
  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/'

This is needed for a later patch that hooks into the helper, but might
be a worthwhile cleanup on its own.

(Michal Hocko provided most of the kerneldoc comment.)

Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:48 -08:00
Paul Burton e11124d8ff MIPS: Remove r2_emul_return from struct thread_info
The r2_emul_return field in struct thread_info was used in order to take
an alternate codepath when returning to userland, which (besides not
implementing certain features) effectively used the eretnc instruction
in place of eret. The difference is that eretnc doesn't clear LLBit, and
therefore doesn't cause a linked load & store sequence to fail due to
emulation like eret would.

The reason eret would usually be used to clear LLBit is so that after
context switching we ensure that a load performed by one task doesn't
influence another task. However commit 7c151d3d5d ("MIPS: Make use of
the ERETNC instruction on MIPS R6") which introduced the r2_emul_return
field and conditional use of eretnc also for some reason began
explicitly clearing LLBit during context switches - despite retaining
the use of eret for everything but returns from the pre-r6 instruction
emulation code.

As LLBit is cleared upon context switches anyway, simplify this by using
eretnc unconditionally for MIPSr6 kernels. This allows us to remove the
4 byte r2_emul_return boolean from struct thread_info, simplify the
return to user code in entry.S and avoid the overhead of tracking &
checking state which we don't need.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14408/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-01-03 16:34:41 +01:00
Paul Burton 35e6de3885 MIPS: traps: Ensure L1 & L2 ECC checking match for CM3 systems
On systems with CM3, we must ensure that the L1 & L2 ECC enables are set
to the same value. This is presumed by the hardware & cache corruption
can occur when it is not the case. Support enabling & disabling the L2
ECC checking on CM3 systems where this is controlled via a GCR, and
ensure that it matches the state of L1 ECC checking. Remove I6400 from
the switch statement it will no longer hit, and which was incorrect
since the L2 ECC enable bit isn't in the CP0 ErrCtl register.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14413/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-01-03 16:34:41 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Maciej W. Rozycki 5a1aca4469 MIPS: Fix FCSR Cause bit handling for correct SIGFPE issue
Sanitize FCSR Cause bit handling, following a trail of past attempts:

* commit 4249548454 ("MIPS: ptrace: Fix FP context restoration FCSR
regression"),

* commit 443c44032a ("MIPS: Always clear FCSR cause bits after
emulation"),

* commit 64bedffe49 ("MIPS: Clear [MSA]FPE CSR.Cause after
notify_die()"),

* commit b1442d39fa ("MIPS: Prevent user from setting FCSR cause
bits"),

* commit b54d2901517d ("Properly handle branch delay slots in connection
with signals.").

Specifically do not mask these bits out in ptrace(2) processing and send
a SIGFPE signal instead whenever a matching pair of an FCSR Cause and
Enable bit is seen as execution of an affected context is about to
resume.  Only then clear Cause bits, and even then do not clear any bits
that are set but masked with the respective Enable bits.  Adjust Cause
bit clearing throughout code likewise, except within the FPU emulator
proper where they are set according to IEEE 754 exceptions raised as the
operation emulated executed.  Do so so that any IEEE 754 exceptions
subject to their default handling are recorded like with operations
executed by FPU hardware.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14460/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-04 01:28:41 +01:00
Paul Burton 752f549982 MIPS: Fix __show_regs() output
Since commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") the output from __show_regs() on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected register output.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14432/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-04 01:01:20 +01:00
Matt Redfearn 41000c5819 MIPS: traps: Fix output of show_code
Since commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") the output from show_code on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected output.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14431/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-04 01:00:49 +01:00
Matt Redfearn fe4e09e701 MIPS: traps: Fix output of show_stacktrace
Since commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") the output from show_stacktrace on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected output. Also
start a new line with printk such that the presence of timing
information does not interfere with output.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14430/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-04 00:58:57 +01:00
Matt Redfearn bcf084de5d MIPS: traps: Fix output of show_backtrace
Since commit 4bcc595ccd ("printk: reinstate KERN_CONT for printing
continuation lines") the output from show_backtrace on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected output.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14429/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-04 00:57:51 +01:00
Paul Burton dabdc1853d MIPS: Print CM error reports upon bus errors
If a bus error occurs on a system with a MIPS Coherence Manager (CM)
then the CM may hold useful diagnostic information. Printing this out
has so far been left up to boards, with the requirement that they
register a board_be_handler function & call mips_cm_error_decode() from
there.

In order to avoid boards other than Malta needing to duplicate this
code, call mips_cm_error_decode() automatically if the board registers
no board_be_handler, and remove the Malta implementation of that.

This patch results in no functional change, but removes a further piece
of platform-specific code.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14350/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-06 18:02:18 +02:00
Matt Redfearn 4b22c693e3 MIPS: traps: Ensure full EBase is written
On CPUs which support the EBase WG (write gate) flag, the most
significant bits of the exception base can be changed. Firmware running
on a VP(E) using MIPS rproc may change EBase to point into the user
segment where the firmware is located such that it can service
interrupts. When control is transferred back to the kernel the EBase
must be switched back into the kernel segment, such that the kernel's
exception vectors are used.

Similarly when vectored interrupts (vint) or vectored external interrupt
controllers (veic) are enabled an exception vector is allocated from
bootmem, and written to the EBase register. Due to the WG flag being
clear, only bits 29:12 will be written. Asside from the rproc case above
this is normally fine (as it will usually be a low allocation within the
KSeg0 range, however when Enhanced Virtual Addressing (EVA) is enabled
the allocation may be outside of the traditional KSeg0/KSeg1 address
range, resulting in the wrong EBase being written.

Correct both cases (configure_exception_vector() for the boot CPU, and
per_cpu_trap_init() for secondary CPUs) to write EBase with the WG flag
first if supported.

On the Malta EVA configuration, KSeg0 is mapped to physical address 0,
and memory is allocated from the KUSeg segment which is mapped to
physical address 0x80000000, which physically aliases the RAM at 0. This
only worked due to the exception base address aliasing the same
underlying RAM that was written to & cache flushed, and due to
flush_icache_range() going beyond the call of duty and flushing from the
L2 cache too (due to the differing physical addresses).

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14150/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
James Hogan c195e079e9 MIPS: traps: Convert ebase to KSEG0
When allocating boot memory for the exception vector when vectored
interrupts (vint) or vectored external interrupt controllers (veic) are
enabled, try to ensure that the virtual address resides in KSeg0 (and
WARN should that not be possible).

This will be helpful on MIPS64 cores supporting the CP0_EBase Write Gate
(WG) bit once we start using the WG bit to write the full ebase into
CP0_EBase, as we ideally need to avoid hitting the architecturally
poorly defined exception base for Cache Errors when CP0_EBase is in
XKPhys.

An exception is made for Enhanced Virtual Addressing (EVA) kernels which
allow segments to be rearranged and to become uncached during cache
error handling, making it valid for ebase to be elsewhere.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14149/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
James Hogan 18022894ec MIPS: traps: 64bit kernels should read CP0_EBase 64bit
When reading the CP0_EBase register containing the WG (write gate) bit,
the ebase variable should be set to the full value of the register, i.e.
on a 64-bit kernel the full 64-bit width of the register via
read_cp0_ebase_64(), and on a 32-bit kernel the full 32-bit width
including bits 31:30 which may be writeable.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14148/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
Paul Gortmaker 9f3b8081a4 MIPS: Migrate exception table users off module.h and onto extable.h
These files were only including module.h for exception table
related functions.  We've now separated that content out into its
own file "extable.h" so now move over to that and avoid all the
extra header content in module.h that we don't really need to compile
these files.

In the case of traps.c we can't dump the module.h include since it is
also used to provide "print_modules".

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13934/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00
Linus Torvalds 4305f42401 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for MIPS for 4.8.  Also includes is a
  minor SSB cleanup as SSB code traditionally is merged through the MIPS
  tree:

  ATH25:
    - MIPS: Add default configuration for ath25

  Boot:
    - For zboot, copy appended dtb to the end of the kernel
    - store the appended dtb address in a variable

  BPF:
    - Fix off by one error in offset allocation

  Cobalt code:
    - Fix typos

  Core code:
    - debugfs_create_file returns NULL on error, so don't use IS_ERR for
      testing for errors.
    - Fix double locking issue in RM7000 S-cache code.  This would only
      affect RM7000 ARC systems on reboot.
    - Fix page table corruption on THP permission changes.
    - Use compat_sys_keyctl for 32 bit userspace on 64 bit kernels.
      David says, there are no compatibility issues raised by this fix.
    - Move some signal code around.
    - Rewrite r4k count/compare clockevent device registration such that
      min_delta_ticks/max_delta_ticks files are guaranteed to be
      initialized.
    - Only register r4k count/compare as clockevent device if we can
      assume the clock to be constant.
    - Fix MSA asm warnings in control reg accessors
    - uasm and tlbex fixes and tweaking.
    - Print segment physical address when EU=1.
    - Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO.
    - CP: Allow booting by VP other than VP 0
    - Cache handling fixes and optimizations for r4k class caches
    - Add hotplug support for R6 processors
    - Cleanup hotplug bits in kconfig
    - traps: return correct si code for accessing nonmapped addresses
    - Remove cpu_has_safe_index_cacheops

  Lantiq:
    - Register IRQ handler for virtual IRQ number
    - Fix EIU interrupt loading code
    - Use the real EXIN count
    - Fix build error.

  Loongson 3:
    - Increase HPET_MIN_PROG_DELTA and decrease HPET_MIN_CYCLES

  Octeon:
    - Delete built-in DTB pruning code for D-Link DSR-1000N.
    - Clean up GPIO definitions in dlink_dsr-1000n.dts.
    - Add more LEDs to the DSR-100n DTS
    - Fix off by one in octeon_irq_gpio_map()
    - Typo fixes
    - Enable SATA by default in cavium_octeon_defconfig
    - Support readq/writeq()
    - Remove forced mappings of USB interrupts.
    - Ensure DMA descriptors are always in the low 4GB
    - Improve USB reset code for OCTEON II.

  Pistachio:
    - Add maintainers entry for pistachio SoC Support
    - Remove plat_setup_iocoherency

  Ralink:
    - Fix pwm UART in spis group pinmux.

  SSB:
    - Change bare unsigned to unsigned int to suit coding style

  Tools:
    - Fix reloc tool compiler warnings.

  Other:
    - Delete use of ARCH_WANT_OPTIONAL_GPIOLIB"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (61 commits)
  MIPS: mm: Fix definition of R6 cache instruction
  MIPS: tools: Fix relocs tool compiler warnings
  MIPS: Cobalt: Fix typo
  MIPS: Octeon: Fix typo
  MIPS: Lantiq: Fix build failure
  MIPS: Use CPHYSADDR to implement mips32 __pa
  MIPS: Octeon: Dlink_dsr-1000n.dts: add more leds.
  MIPS: Octeon: Clean up GPIO definitions in dlink_dsr-1000n.dts.
  MIPS: Octeon: Delete built-in DTB pruning code for D-Link DSR-1000N.
  MIPS: store the appended dtb address in a variable
  MIPS: ZBOOT: copy appended dtb to the end of the kernel
  MIPS: ralink: fix spis group pinmux
  MIPS: Factor o32 specific code into signal_o32.c
  MIPS: non-exec stack & heap when non-exec PT_GNU_STACK is present
  MIPS: Use per-mm page to execute branch delay slot instructions
  MIPS: Modify error handling
  MIPS: c-r4k: Use SMP calls for CM indexed cache ops
  MIPS: c-r4k: Avoid small flush_icache_range SMP calls
  MIPS: c-r4k: Local flush_icache_range cache op override
  MIPS: c-r4k: Split r4k_flush_kernel_vmap_range()
  ...
2016-08-06 09:13:11 -04:00