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20801 Commits (88e4901d3ebd394ba079ea26536b8500fbd8e68b)

Author SHA1 Message Date
Christophe Leroy 9b9374cf1e powerpc/hugetlb: Fix 8M hugepages on 8xx
commit 50a175dd18 upstream.

With HW assistance all page tables must be 4k aligned, the 8xx drops
the last 12 bits during the walk.

Redefine HUGEPD_SHIFT_MASK to mask last 12 bits out. HUGEPD_SHIFT_MASK
is used to for alignment of page table cache.

Fixes: 22569b881d ("powerpc/8xx: Enable 8M hugepage support with HW assistance")
Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/778b1a248c4c7ca79640eeff7740044da6a220a0.1581264115.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:18 +01:00
Christophe Leroy 723a44f228 powerpc/hugetlb: Fix 512k hugepages on 8xx with 16k page size
commit f2b67ef90b upstream.

Commit 55c8fc3f49 ("powerpc/8xx: reintroduce 16K pages with HW
assistance") redefined pte_t as a struct of 4 pte_basic_t, because
in 16K pages mode there are four identical entries in the
page table. But the size of hugepage tables is calculated based
of the size of (void *). Therefore, we end up with page tables
of size 1k instead of 4k for 512k pages.

As 512k hugepage tables are the same size as standard page tables,
ie 4k, use the standard page tables instead of PGT_CACHE tables.

Fixes: 3fb69c6a1a ("powerpc/8xx: Enable 512k hugepage support with HW assistance")
Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/90ec56a2315be602494619ed0223bba3b0b8d619.1580997007.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:18 +01:00
Christophe Leroy 2ffeef3db3 powerpc/entry: Fix an #if which should be an #ifdef in entry_32.S
commit 9eb425b2e0 upstream.

Fixes: 12c3f1fd87 ("powerpc/32s: get rid of CPU_FTR_601 feature")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a99fc0ad65b87a1ba51cfa3e0e9034ee294c3e07.1582034961.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:18 +01:00
Gustavo Luiz Duarte 04e3f1d1e1 powerpc/tm: Fix clearing MSR[TS] in current when reclaiming on signal delivery
commit 2464cc4c34 upstream.

After a treclaim, we expect to be in non-transactional state. If we
don't clear the current thread's MSR[TS] before we get preempted, then
tm_recheckpoint_new_task() will recheckpoint and we get rescheduled in
suspended transaction state.

When handling a signal caught in transactional state,
handle_rt_signal64() calls get_tm_stackpointer() that treclaims the
transaction using tm_reclaim_current() but without clearing the
thread's MSR[TS]. This can cause the TM Bad Thing exception below if
later we pagefault and get preempted trying to access the user's
sigframe, using __put_user(). Afterwards, when we are rescheduled back
into do_page_fault() (but now in suspended state since the thread's
MSR[TS] was not cleared), upon executing 'rfid' after completion of
the page fault handling, the exception is raised because a transition
from suspended to non-transactional state is invalid.

  Unexpected TM Bad Thing exception at c00000000000de44 (msr 0x8000000302a03031) tm_scratch=800000010280b033
  Oops: Unrecoverable exception, sig: 6 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  CPU: 25 PID: 15547 Comm: a.out Not tainted 5.4.0-rc2 #32
  NIP:  c00000000000de44 LR: c000000000034728 CTR: 0000000000000000
  REGS: c00000003fe7bd70 TRAP: 0700   Not tainted  (5.4.0-rc2)
  MSR:  8000000302a03031 <SF,VEC,VSX,FP,ME,IR,DR,LE,TM[SE]>  CR: 44000884  XER: 00000000
  CFAR: c00000000000dda4 IRQMASK: 0
  PACATMSCRATCH: 800000010280b033
  GPR00: c000000000034728 c000000f65a17c80 c000000001662800 00007fffacf3fd78
  GPR04: 0000000000001000 0000000000001000 0000000000000000 c000000f611f8af0
  GPR08: 0000000000000000 0000000078006001 0000000000000000 000c000000000000
  GPR12: c000000f611f84b0 c00000003ffcb200 0000000000000000 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000f611f8140
  GPR24: 0000000000000000 00007fffacf3fd68 c000000f65a17d90 c000000f611f7800
  GPR28: c000000f65a17e90 c000000f65a17e90 c000000001685e18 00007fffacf3f000
  NIP [c00000000000de44] fast_exception_return+0xf4/0x1b0
  LR [c000000000034728] handle_rt_signal64+0x78/0xc50
  Call Trace:
  [c000000f65a17c80] [c000000000034710] handle_rt_signal64+0x60/0xc50 (unreliable)
  [c000000f65a17d30] [c000000000023640] do_notify_resume+0x330/0x460
  [c000000f65a17e20] [c00000000000dcc4] ret_from_except_lite+0x70/0x74
  Instruction dump:
  7c4ff120 e8410170 7c5a03a6 38400000 f8410060 e8010070 e8410080 e8610088
  60000000 60000000 e8810090 e8210078 <4c000024> 48000000 e8610178 88ed0989
  ---[ end trace 93094aa44b442f87 ]---

The simplified sequence of events that triggers the above exception is:

  ...				# userspace in NON-TRANSACTIONAL state
  tbegin			# userspace in TRANSACTIONAL state
  signal delivery		# kernelspace in SUSPENDED state
  handle_rt_signal64()
    get_tm_stackpointer()
      treclaim			# kernelspace in NON-TRANSACTIONAL state
    __put_user()
      page fault happens. We will never get back here because of the TM Bad Thing exception.

  page fault handling kicks in and we voluntarily preempt ourselves
  do_page_fault()
    __schedule()
      __switch_to(other_task)

  our task is rescheduled and we recheckpoint because the thread's MSR[TS] was not cleared
  __switch_to(our_task)
    switch_to_tm()
      tm_recheckpoint_new_task()
        trechkpt			# kernelspace in SUSPENDED state

  The page fault handling resumes, but now we are in suspended transaction state
  do_page_fault()    completes
  rfid     <----- trying to get back where the page fault happened (we were non-transactional back then)
  TM Bad Thing			# illegal transition from suspended to non-transactional

This patch fixes that issue by clearing the current thread's MSR[TS]
just after treclaim in get_tm_stackpointer() so that we stay in
non-transactional state in case we are preempted. In order to make
treclaim and clearing the thread's MSR[TS] atomic from a preemption
perspective when CONFIG_PREEMPT is set, preempt_disable/enable() is
used. It's also necessary to save the previous value of the thread's
MSR before get_tm_stackpointer() is called so that it can be exposed
to the signal handler later in setup_tm_sigcontexts() to inform the
userspace MSR at the moment of the signal delivery.

Found with tm-signal-context-force-tm kernel selftest.

Fixes: 2b0a576d15 ("powerpc: Add new transactional memory state to the signal context")
Cc: stable@vger.kernel.org # v3.9
Signed-off-by: Gustavo Luiz Duarte <gustavold@linux.ibm.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200211033831.11165-1-gustavold@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:17 +01:00
Sam Bobroff a03b3cea86 powerpc/eeh: Fix deadlock handling dead PHB
commit d4f194ed9e upstream.

Recovering a dead PHB can currently cause a deadlock as the PCI
rescan/remove lock is taken twice.

This is caused as part of an existing bug in
eeh_handle_special_event(). The pe is processed while traversing the
PHBs even though the pe is unrelated to the loop. This causes the pe
to be, incorrectly, processed more than once.

Untangling this section can move the pe processing out of the loop and
also outside the locked section, correcting both problems.

Fixes: 2e25505147 ("powerpc/eeh: Fix crash when edev->pdev changes")
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com>
Tested-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0547e82dbf90ee0729a2979a8cac5c91665c621f.1581051445.git.sbobroff@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:17 +01:00
Christophe Leroy 9e1fab4450 powerpc/8xx: Fix clearing of bits 20-23 in ITLB miss
commit a4031afb9d upstream.

In ITLB miss handled the line supposed to clear bits 20-23 on the L2
ITLB entry is buggy and does indeed nothing, leading to undefined
value which could allow execution when it shouldn't.

Properly do the clearing with the relevant instruction.

Fixes: 74fabcadfd ("powerpc/8xx: don't use r12/SPRN_SPRG_SCRATCH2 in TLB Miss handlers")
Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Leonardo Bras <leonardo@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4f70c2778163affce8508a210f65d140e84524b4.1581272050.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:17 +01:00
Alexandre Ghiti a531e6ba85 powerpc: Do not consider weak unresolved symbol relocations as bad
[ Upstream commit 43e76cd368 ]

Commit 8580ac9404 ("bpf: Process in-kernel BTF") introduced two weak
symbols that may be unresolved at link time which result in an absolute
relocation to 0. relocs_check.sh emits the following warning:

"WARNING: 2 bad relocations
c000000001a41478 R_PPC64_ADDR64    _binary__btf_vmlinux_bin_start
c000000001a41480 R_PPC64_ADDR64    _binary__btf_vmlinux_bin_end"

whereas those relocations are legitimate even for a relocatable kernel
compiled with -pie option.

relocs_check.sh already excluded some weak unresolved symbols explicitly:
remove those hardcoded symbols and add some logic that parses the symbols
using nm, retrieves all the weak unresolved symbols and excludes those from
the list of the potential bad relocations.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200118170335.21440-1-alex@ghiti.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:37:00 +01:00
Christophe Leroy 7288d5338c powerpc/mm: Don't log user reads to 0xffffffff
[ Upstream commit 0f9aee0cb9 ]

Running vdsotest leaves many times the following log:

  [   79.629901] vdsotest[396]: User access of kernel address (ffffffff) - exploit attempt? (uid: 0)

A pointer set to (-1) is likely a programming error similar to
a NULL pointer and is not worth logging as an exploit attempt.

Don't log user accesses to 0xffffffff.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0728849e826ba16f1fbd6fa7f5c6cc87bd64e097.1577087627.git.christophe.leroy@c-s.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:58 +01:00
Michael Bringmann 93df1b23b1 powerpc/pseries/lparcfg: Fix display of Maximum Memory
[ Upstream commit f1dbc1c5c7 ]

Correct overflow problem in calculation and display of Maximum Memory
value to syscfg.

Signed-off-by: Michael Bringmann <mwb@linux.ibm.com>
[mpe: Only n_lmbs needs casting to unsigned long]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5577aef8-1d5a-ca95-ff0a-9c7b5977e5bf@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:57 +01:00
Oliver O'Halloran 3f6c8de753 powerpc/sriov: Remove VF eeh_dev state when disabling SR-IOV
[ Upstream commit 1fb4124ca9 ]

When disabling virtual functions on an SR-IOV adapter we currently do not
correctly remove the EEH state for the now-dead virtual functions. When
removing the pci_dn that was created for the VF when SR-IOV was enabled
we free the corresponding eeh_dev without removing it from the child device
list of the eeh_pe that contained it. This can result in crashes due to the
use-after-free.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Tested-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190821062655.19735-1-oohall@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:56 +01:00
zhengbin 88cf251d3c KVM: PPC: Remove set but not used variable 'ra', 'rs', 'rt'
[ Upstream commit 4de0a83554 ]

Fixes gcc '-Wunused-but-set-variable' warning:

arch/powerpc/kvm/emulate_loadstore.c: In function kvmppc_emulate_loadstore:
arch/powerpc/kvm/emulate_loadstore.c:87:6: warning: variable ra set but not used [-Wunused-but-set-variable]
arch/powerpc/kvm/emulate_loadstore.c: In function kvmppc_emulate_loadstore:
arch/powerpc/kvm/emulate_loadstore.c:87:10: warning: variable rs set but not used [-Wunused-but-set-variable]
arch/powerpc/kvm/emulate_loadstore.c: In function kvmppc_emulate_loadstore:
arch/powerpc/kvm/emulate_loadstore.c:87:14: warning: variable rt set but not used [-Wunused-but-set-variable]

They are not used since commit 2b33cb585f ("KVM: PPC: Reimplement
LOAD_FP/STORE_FP instruction mmio emulation with analyse_instr() input")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:51 +01:00
Oliver O'Halloran 8be3ac46ef powerpc/iov: Move VF pdev fixup into pcibios_fixup_iov()
[ Upstream commit 965c94f309 ]

An ioda_pe for each VF is allocated in pnv_pci_sriov_enable() before
the pci_dev for the VF is created. We need to set the pe->pdev pointer
at some point after the pci_dev is created. Currently we do that in:

pcibios_bus_add_device()
	pnv_pci_dma_dev_setup() (via phb->ops.dma_dev_setup)
		/* fixup is done here */
		pnv_pci_ioda_dma_dev_setup() (via pnv_phb->dma_dev_setup)

The fixup needs to be done before setting up DMA for for the VF's PE,
but there's no real reason to delay it until this point. Move the
fixup into pnv_pci_ioda_fixup_iov() so the ordering is:

	pcibios_add_device()
		pnv_pci_ioda_fixup_iov() (via ppc_md.pcibios_fixup_sriov)

	pcibios_bus_add_device()
		...

This isn't strictly required, but it's a slightly more logical place
to do the fixup and it simplifies pnv_pci_dma_dev_setup().

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200110070207.439-4-oohall@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:30 +01:00
Oliver O'Halloran 271b18405e powerpc/powernv/iov: Ensure the pdn for VFs always contains a valid PE number
[ Upstream commit 3b5b9997b3 ]

On pseries there is a bug with adding hotplugged devices to an IOMMU
group. For a number of dumb reasons fixing that bug first requires
re-working how VFs are configured on PowerNV. For background, on
PowerNV we use the pcibios_sriov_enable() hook to do two things:

  1. Create a pci_dn structure for each of the VFs, and
  2. Configure the PHB's internal BARs so the MMIO range for each VF
     maps to a unique PE.

Roughly speaking a PE is the hardware counterpart to a Linux IOMMU
group since all the devices in a PE share the same IOMMU table. A PE
also defines the set of devices that should be isolated in response to
a PCI error (i.e. bad DMA, UR/CA, AER events, etc). When isolated all
MMIO and DMA traffic to and from devicein the PE is blocked by the
root complex until the PE is recovered by the OS.

The requirement to block MMIO causes a giant headache because the P8
PHB generally uses a fixed mapping between MMIO addresses and PEs. As
a result we need to delay configuring the IOMMU groups for device
until after MMIO resources are assigned. For physical devices (i.e.
non-VFs) the PE assignment is done in pcibios_setup_bridge() which is
called immediately after the MMIO resources for downstream
devices (and the bridge's windows) are assigned. For VFs the setup is
more complicated because:

  a) pcibios_setup_bridge() is not called again when VFs are activated, and
  b) The pci_dev for VFs are created by generic code which runs after
     pcibios_sriov_enable() is called.

The work around for this is a two step process:

  1. A fixup in pcibios_add_device() is used to initialised the cached
     pe_number in pci_dn, then
  2. A bus notifier then adds the device to the IOMMU group for the PE
     specified in pci_dn->pe_number.

A side effect fixing the pseries bug mentioned in the first paragraph
is moving the fixup out of pcibios_add_device() and into
pcibios_bus_add_device(), which is called much later. This results in
step 2. failing because pci_dn->pe_number won't be initialised when
the bus notifier is run.

We can fix this by removing the need for the fixup. The PE for a VF is
known before the VF is even scanned so we can initialise
pci_dn->pe_number pcibios_sriov_enable() instead. Unfortunately,
moving the initialisation causes two problems:

  1. We trip the WARN_ON() in the current fixup code, and
  2. The EEH core clears pdn->pe_number when recovering a VF and
     relies on the fixup to correctly re-set it.

The only justification for either of these is a comment in
eeh_rmv_device() suggesting that pdn->pe_number *must* be set to
IODA_INVALID_PE in order for the VF to be scanned. However, this
comment appears to have no basis in reality. Both bugs can be fixed by
just deleting the code.

Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191028085424.12006-1-oohall@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:26 +01:00
Alexey Kardashevskiy c4faf627c7 powerpc/pseries: Allow not having ibm, hypertas-functions::hcall-multi-tce for DDW
commit 7559d3d295 upstream.

By default a pseries guest supports a H_PUT_TCE hypercall which maps
a single IOMMU page in a DMA window. Additionally the hypervisor may
support H_PUT_TCE_INDIRECT/H_STUFF_TCE which update multiple TCEs at once;
this is advertised via the device tree /rtas/ibm,hypertas-functions
property which Linux converts to FW_FEATURE_MULTITCE.

FW_FEATURE_MULTITCE is checked when dma_iommu_ops is used; however
the code managing the huge DMA window (DDW) ignores it and calls
H_PUT_TCE_INDIRECT even if it is explicitly disabled via
the "multitce=off" kernel command line parameter.

This adds FW_FEATURE_MULTITCE checking to the DDW code path.

This changes tce_build_pSeriesLP to take liobn and page size as
the huge window does not have iommu_table descriptor which usually
the place to store these numbers.

Fixes: 4e8b0cf46b ("powerpc/pseries: Add support for dynamic dma windows")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Tested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191216041924.42318-3-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:16 -05:00
Tyrel Datwyler cff30edec9 powerpc/pseries/vio: Fix iommu_table use-after-free refcount warning
commit aff8c8242b upstream.

Commit e5afdf9dd5 ("powerpc/vfio_spapr_tce: Add reference counting to
iommu_table") missed an iommu_table allocation in the pseries vio code.
The iommu_table is allocated with kzalloc and as a result the associated
kref gets a value of zero. This has the side effect that during a DLPAR
remove of the associated virtual IOA the iommu_tce_table_put() triggers
a use-after-free underflow warning.

Call Trace:
[c0000002879e39f0] [c00000000071ecb4] refcount_warn_saturate+0x184/0x190
(unreliable)
[c0000002879e3a50] [c0000000000500ac] iommu_tce_table_put+0x9c/0xb0
[c0000002879e3a70] [c0000000000f54e4] vio_dev_release+0x34/0x70
[c0000002879e3aa0] [c00000000087cfa4] device_release+0x54/0xf0
[c0000002879e3b10] [c000000000d64c84] kobject_cleanup+0xa4/0x240
[c0000002879e3b90] [c00000000087d358] put_device+0x28/0x40
[c0000002879e3bb0] [c0000000007a328c] dlpar_remove_slot+0x15c/0x250
[c0000002879e3c50] [c0000000007a348c] remove_slot_store+0xac/0xf0
[c0000002879e3cd0] [c000000000d64220] kobj_attr_store+0x30/0x60
[c0000002879e3cf0] [c0000000004ff13c] sysfs_kf_write+0x6c/0xa0
[c0000002879e3d10] [c0000000004fde4c] kernfs_fop_write+0x18c/0x260
[c0000002879e3d60] [c000000000410f3c] __vfs_write+0x3c/0x70
[c0000002879e3d80] [c000000000415408] vfs_write+0xc8/0x250
[c0000002879e3dd0] [c0000000004157dc] ksys_write+0x7c/0x120
[c0000002879e3e20] [c00000000000b278] system_call+0x5c/0x68

Further, since the refcount was always zero the iommu_tce_table_put()
fails to call the iommu_table release function resulting in a leak.

Fix this issue be initilizing the iommu_table kref immediately after
allocation.

Fixes: e5afdf9dd5 ("powerpc/vfio_spapr_tce: Add reference counting to iommu_table")
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1579558202-26052-1-git-send-email-tyreld@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:16 -05:00
Vaibhav Jain 5ca556d5ed powerpc/papr_scm: Fix leaking 'bus_desc.provider_name' in some paths
commit 5649607a8d upstream.

String 'bus_desc.provider_name' allocated inside
papr_scm_nvdimm_init() will leaks in case call to
nvdimm_bus_register() fails or when papr_scm_remove() is called.

This minor patch ensures that 'bus_desc.provider_name' is freed in
error path for nvdimm_bus_register() as well as in papr_scm_remove().

Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200122155140.120429-1-vaibhav@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:16 -05:00
Christophe Leroy 05a23f4364 powerpc/ptdump: Only enable PPC_CHECK_WX with STRICT_KERNEL_RWX
commit f509247b08 upstream.

ptdump_check_wx() is called from mark_rodata_ro() which only exists
when CONFIG_STRICT_KERNEL_RWX is selected.

Fixes: 453d87f6a8 ("powerpc/mm: Warn if W+X pages found on boot")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/922d4939c735c6b52b4137838bcc066fffd4fc33.1578989545.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:16 -05:00
Christophe Leroy 17f37249d7 powerpc/ptdump: Fix W+X verification call in mark_rodata_ro()
commit e26ad936dd upstream.

ptdump_check_wx() also have to be called when pages are mapped
by blocks.

Fixes: 453d87f6a8 ("powerpc/mm: Warn if W+X pages found on boot")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/37517da8310f4457f28921a4edb88fb21d27b62a.1578989531.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:16 -05:00
Ram Pai 6d7edac146 Revert "powerpc/pseries/iommu: Don't use dma_iommu_ops on secure guests"
commit d862b44133 upstream.

This reverts commit edea902c1c.

At the time the change allowed direct DMA ops for secure VMs; however
since then we switched on using SWIOTLB backed with IOMMU (direct mapping)
and to make this work, we need dma_iommu_ops which handles all cases
including TCE mapping I/O pages in the presence of an IOMMU.

Fixes: edea902c1c ("powerpc/pseries/iommu: Don't use dma_iommu_ops on secure guests")
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[aik: added "revert" and "fixes:"]
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Tested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191216041924.42318-2-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:16 -05:00
Christophe Leroy 866323ccc1 powerpc/kuap: Fix set direction in allow/prevent_user_access()
[ Upstream commit 1d8f739b07 ]

__builtin_constant_p() always return 0 for pointers, so on RADIX
we always end up opening both direction (by writing 0 in SPR29):

  0000000000000170 <._copy_to_user>:
  ...
   1b0:	4c 00 01 2c 	isync
   1b4:	39 20 00 00 	li      r9,0
   1b8:	7d 3d 03 a6 	mtspr   29,r9
   1bc:	4c 00 01 2c 	isync
   1c0:	48 00 00 01 	bl      1c0 <._copy_to_user+0x50>
  			1c0: R_PPC64_REL24	.__copy_tofrom_user
  ...
  0000000000000220 <._copy_from_user>:
  ...
   2ac:	4c 00 01 2c 	isync
   2b0:	39 20 00 00 	li      r9,0
   2b4:	7d 3d 03 a6 	mtspr   29,r9
   2b8:	4c 00 01 2c 	isync
   2bc:	7f c5 f3 78 	mr      r5,r30
   2c0:	7f 83 e3 78 	mr      r3,r28
   2c4:	48 00 00 01 	bl      2c4 <._copy_from_user+0xa4>
  			2c4: R_PPC64_REL24	.__copy_tofrom_user
  ...

Use an explicit parameter for direction selection, so that GCC
is able to see it is a constant:

  00000000000001b0 <._copy_to_user>:
  ...
   1f0:	4c 00 01 2c 	isync
   1f4:	3d 20 40 00 	lis     r9,16384
   1f8:	79 29 07 c6 	rldicr  r9,r9,32,31
   1fc:	7d 3d 03 a6 	mtspr   29,r9
   200:	4c 00 01 2c 	isync
   204:	48 00 00 01 	bl      204 <._copy_to_user+0x54>
  			204: R_PPC64_REL24	.__copy_tofrom_user
  ...
  0000000000000260 <._copy_from_user>:
  ...
   2ec:	4c 00 01 2c 	isync
   2f0:	39 20 ff ff 	li      r9,-1
   2f4:	79 29 00 04 	rldicr  r9,r9,0,0
   2f8:	7d 3d 03 a6 	mtspr   29,r9
   2fc:	4c 00 01 2c 	isync
   300:	7f c5 f3 78 	mr      r5,r30
   304:	7f 83 e3 78 	mr      r3,r28
   308:	48 00 00 01 	bl      308 <._copy_from_user+0xa8>
  			308: R_PPC64_REL24	.__copy_tofrom_user
  ...

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Spell out the directions, s/KUAP_R/KUAP_READ/ etc.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f4e88ec4941d5facb35ce75026b0112f980086c3.1579866752.git.christophe.leroy@c-s.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-11 04:35:55 -08:00
Sean Christopherson 7426ddf01f KVM: Use vcpu-specific gva->hva translation when querying host page size
[ Upstream commit f9b84e1922 ]

Use kvm_vcpu_gfn_to_hva() when retrieving the host page size so that the
correct set of memslots is used when handling x86 page faults in SMM.

Fixes: 54bf36aac5 ("KVM: x86: use vcpu-specific functions to read/write/translate GFNs")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-11 04:35:54 -08:00
Nathan Chancellor bf45386cef powerpc/44x: Adjust indentation in ibm4xx_denali_fixup_memsize
commit c3aae14e5d upstream.

Clang warns:

../arch/powerpc/boot/4xx.c:231:3: warning: misleading indentation;
statement is not part of the previous 'else' [-Wmisleading-indentation]
        val = SDRAM0_READ(DDR0_42);
        ^
../arch/powerpc/boot/4xx.c:227:2: note: previous statement is here
        else
        ^

This is because there is a space at the beginning of this line; remove
it so that the indentation is consistent according to the Linux kernel
coding style and clang no longer warns.

Fixes: d23f509929 ("[POWERPC] 4xx: Adds decoding of 440SPE memory size to boot wrapper library")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://github.com/ClangBuiltLinux/linux/issues/780
Link: https://lore.kernel.org/r/20191209200338.12546-1-natechancellor@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:45 -08:00
Peter Zijlstra 806cabd311 mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush
commit 0ed1325967 upstream.

Architectures for which we have hardware walkers of Linux page table
should flush TLB on mmu gather batch allocation failures and batch flush.
Some architectures like POWER supports multiple translation modes (hash
and radix) and in the case of POWER only radix translation mode needs the
above TLBI.  This is because for hash translation mode kernel wants to
avoid this extra flush since there are no hardware walkers of linux page
table.  With radix translation, the hardware also walks linux page table
and with that, kernel needs to make sure to TLB invalidate page walk cache
before page table pages are freed.

More details in commit d86564a2f0 ("mm/tlb, x86/mm: Support invalidating
TLB caches for RCU_TABLE_FREE")

The changes to sparc are to make sure we keep the old behavior since we
are now removing HAVE_RCU_TABLE_NO_INVALIDATE.  The default value for
tlb_needs_table_invalidate is to always force an invalidate and sparc can
avoid the table invalidate.  Hence we define tlb_needs_table_invalidate to
false for sparc architecture.

Link: http://lkml.kernel.org/r/20200116064531.483522-3-aneesh.kumar@linux.ibm.com
Fixes: a46cc7a90f ("powerpc/mm/radix: Improve TLB/PWC flushes")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>	[powerpc]
Cc: <stable@vger.kernel.org>	[4.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:42 -08:00
Sean Christopherson 9213699efd KVM: PPC: Book3S PR: Free shared page if mmu initialization fails
commit cb10bf9194 upstream.

Explicitly free the shared page if kvmppc_mmu_init() fails during
kvmppc_core_vcpu_create(), as the page is freed only in
kvmppc_core_vcpu_free(), which is not reached via kvm_vcpu_uninit().

Fixes: 96bc451a15 ("KVM: PPC: Introduce shared page")
Cc: stable@vger.kernel.org
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:39 -08:00
Sean Christopherson b2301deda8 KVM: PPC: Book3S HV: Uninit vCPU if vcore creation fails
commit 1a978d9d3e upstream.

Call kvm_vcpu_uninit() if vcore creation fails to avoid leaking any
resources allocated by kvm_vcpu_init(), i.e. the vcpu->run page.

Fixes: 371fefd6f2 ("KVM: PPC: Allow book3s_hv guests to use SMT processor modes")
Cc: stable@vger.kernel.org
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:39 -08:00
Michael Ellerman 246a54895a powerpc/futex: Fix incorrect user access blocking
commit 9dc086f1e9 upstream.

The early versions of our kernel user access prevention (KUAP) were
written by Russell and Christophe, and didn't have separate
read/write access.

At some point I picked up the series and added the read/write access,
but I failed to update the usages in futex.h to correctly allow read
and write.

However we didn't notice because of another bug which was causing the
low-level code to always enable read and write. That bug was fixed
recently in commit 1d8f739b07 ("powerpc/kuap: Fix set direction in
allow/prevent_user_access()").

futex_atomic_cmpxchg_inatomic() is passed the user address as %3 and
does:

  1:     lwarx   %1,  0, %3
         cmpw    0,  %1, %4
         bne-    3f
  2:     stwcx.  %5,  0, %3

Which clearly loads and stores from/to %3. The logic in
arch_futex_atomic_op_inuser() is similar, so fix both of them to use
allow_read_write_user().

Without this fix, and with PPC_KUAP_DEBUG=y, we see eg:

  Bug: Read fault blocked by AMR!
  WARNING: CPU: 94 PID: 149215 at arch/powerpc/include/asm/book3s/64/kup-radix.h:126 __do_page_fault+0x600/0xf30
  CPU: 94 PID: 149215 Comm: futex_requeue_p Tainted: G        W         5.5.0-rc7-gcc9x-g4c25df5640ae #1
  ...
  NIP [c000000000070680] __do_page_fault+0x600/0xf30
  LR [c00000000007067c] __do_page_fault+0x5fc/0xf30
  Call Trace:
  [c00020138e5637e0] [c00000000007067c] __do_page_fault+0x5fc/0xf30 (unreliable)
  [c00020138e5638c0] [c00000000000ada8] handle_page_fault+0x10/0x30
  --- interrupt: 301 at cmpxchg_futex_value_locked+0x68/0xd0
      LR = futex_lock_pi_atomic+0xe0/0x1f0
  [c00020138e563bc0] [c000000000217b50] futex_lock_pi_atomic+0x80/0x1f0 (unreliable)
  [c00020138e563c30] [c00000000021b668] futex_requeue+0x438/0xb60
  [c00020138e563d60] [c00000000021c6cc] do_futex+0x1ec/0x2b0
  [c00020138e563d90] [c00000000021c8b8] sys_futex+0x128/0x200
  [c00020138e563e20] [c00000000000b7ac] system_call+0x5c/0x68

Fixes: de78a9c42a ("powerpc: Add a framework for Kernel Userspace Access Protection")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: syzbot+e808452bad7c375cbee6@syzkaller-ppc64.appspotmail.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Link: https://lore.kernel.org/r/20200207122145.11928-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:31 -08:00
Michael Ellerman bae74e7ac8 of: Add OF_DMA_DEFAULT_COHERENT & select it on powerpc
commit dabf6b36b8 upstream.

There's an OF helper called of_dma_is_coherent(), which checks if a
device has a "dma-coherent" property to see if the device is coherent
for DMA.

But on some platforms devices are coherent by default, and on some
platforms it's not possible to update existing device trees to add the
"dma-coherent" property.

So add a Kconfig symbol to allow arch code to tell
of_dma_is_coherent() that devices are coherent by default, regardless
of the presence of the property.

Select that symbol on powerpc when NOT_COHERENT_CACHE is not set, ie.
when the system has a coherent cache.

Fixes: 92ea637ede ("of: introduce of_dma_is_coherent() helper")
Cc: stable@vger.kernel.org # v3.16+
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:25 -08:00
Christophe Leroy 5b92f86c84 powerpc/32s: Fix CPU wake-up from sleep mode
commit 9933819099 upstream.

Commit f7354ccac8 ("powerpc/32: Remove CURRENT_THREAD_INFO and
rename TI_CPU") broke the CPU wake-up from sleep mode (i.e. when
_TLF_SLEEPING is set) by delaying the tovirt(r2, r2).

This is because r2 is not restored by fast_exception_return. It used
to work (by chance ?) because CPU wake-up interrupt never comes from
user, so r2 is expected to point to 'current' on return.

Commit e2fb9f5444 ("powerpc/32: Prepare for Kernel Userspace Access
Protection") broke it even more by clobbering r0 which is not
restored by fast_exception_return either.

Use r6 instead of r0. This is possible because r3-r6 are restored by
fast_exception_return and only r3-r5 are used for exception arguments.

For r2 it could be converted back to virtual address, but stay on the
safe side and restore it from the stack instead. It should be live
in the cache at that moment, so loading from the stack should make
no difference compared to converting it from phys to virt.

Fixes: f7354ccac8 ("powerpc/32: Remove CURRENT_THREAD_INFO and rename TI_CPU")
Fixes: e2fb9f5444 ("powerpc/32: Prepare for Kernel Userspace Access Protection")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6d02c3ae6ad77af34392e98117e44c2bf6d13ba1.1580121710.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:18 -08:00
Christophe Leroy 4135a03fdf powerpc/32s: Fix bad_kuap_fault()
commit 6ec20aa2e5 upstream.

At the moment, bad_kuap_fault() reports a fault only if a bad access
to userspace occurred while access to userspace was not granted.

But if a fault occurs for a write outside the allowed userspace
segment(s) that have been unlocked, bad_kuap_fault() fails to
detect it and the kernel loops forever in do_page_fault().

Fix it by checking that the accessed address is within the allowed
range.

Fixes: a68c31fc01 ("powerpc/32s: Implement Kernel Userspace Access Protection")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f48244e9485ada0a304ed33ccbb8da271180c80d.1579866752.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:18 -08:00
Pingfan Liu 1bd3b871af powerpc/pseries: Advance pfn if section is not present in lmb_is_removable()
commit fbee6ba2dc upstream.

In lmb_is_removable(), if a section is not present, it should continue
to test the rest of the sections in the block. But the current code
fails to do so.

Fixes: 51925fb3c5 ("powerpc/pseries: Implement memory hotplug remove in the kernel")
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1578632042-12415-1-git-send-email-kernelfans@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:17 -08:00
Sukadev Bhattiprolu 02c4699fb6 powerpc/xmon: don't access ASDR in VMs
commit c2a20711fc upstream.

ASDR is HV-privileged and must only be accessed in HV-mode.
Fixes a Program Check (0x700) when xmon in a VM dumps SPRs.

Fixes: d1e1b351f5 ("powerpc/xmon: Add ISA v3.0 SPRs to SPR dump")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200107021633.GB29843@us.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:17 -08:00
Christophe Leroy 796085dbe3 powerpc/ptdump: Fix W+X verification
commit d80ae83f1f upstream.

Verification cannot rely on simple bit checking because on some
platforms PAGE_RW is 0, checking that a page is not W means
checking that PAGE_RO is set instead of checking that PAGE_RW
is not set.

Use pte helpers instead of checking bits.

Fixes: 453d87f6a8 ("powerpc/mm: Warn if W+X pages found on boot")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0d894839fdbb19070f0e1e4140363be4f2bb62fc.1578989540.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:17 -08:00
Aneesh Kumar K.V 2cabe61ab8 powerpc/mmu_gather: enable RCU_TABLE_FREE even for !SMP case
commit 12e4d53f3f upstream.

Patch series "Fixup page directory freeing", v4.

This is a repost of patch series from Peter with the arch specific changes
except ppc64 dropped.  ppc64 changes are added here because we are redoing
the patch series on top of ppc64 changes.  This makes it easy to backport
these changes.  Only the first 2 patches need to be backported to stable.

The thing is, on anything SMP, freeing page directories should observe the
exact same order as normal page freeing:

 1) unhook page/directory
 2) TLB invalidate
 3) free page/directory

Without this, any concurrent page-table walk could end up with a
Use-after-Free.  This is esp.  trivial for anything that has software
page-table walkers (HAVE_FAST_GUP / software TLB fill) or the hardware
caches partial page-walks (ie.  caches page directories).

Even on UP this might give issues since mmu_gather is preemptible these
days.  An interrupt or preempted task accessing user pages might stumble
into the free page if the hardware caches page directories.

This patch series fixes ppc64 and add generic MMU_GATHER changes to
support the conversion of other architectures.  I haven't added patches
w.r.t other architecture because they are yet to be acked.

This patch (of 9):

A followup patch is going to make sure we correctly invalidate page walk
cache before we free page table pages.  In order to keep things simple
enable RCU_TABLE_FREE even for !SMP so that we don't have to fixup the
!SMP case differently in the followup patch

!SMP case is right now broken for radix translation w.r.t page walk
cache flush.  We can get interrupted in between page table free and
that would imply we have page walk cache entries pointing to tables
which got freed already.  Michael said "both our platforms that run on
Power9 force SMP on in Kconfig, so the !SMP case is unlikely to be a
problem for anyone in practice, unless they've hacked their kernel to
build it !SMP."

Link: http://lkml.kernel.org/r/20200116064531.483522-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:17 -08:00
Madalin Bucur 1ce13ed0a5 powerpc/fsl/dts: add fsl,erratum-a011043
[ Upstream commit 73d527aef6 ]

Add fsl,erratum-a011043 to internal MDIO buses.
Software may get false read error when reading internal
PCS registers through MDIO. As a workaround, all internal
MDIO accesses should ignore the MDIO_CFG[MDIO_RD_ER] bit.

Signed-off-by: Madalin Bucur <madalin.bucur@oss.nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-05 21:22:51 +00:00
Frederic Barrat 7cf7a7d025 powerpc/xive: Discard ESB load value when interrupt is invalid
commit 17328f218f upstream.

A load on an ESB page returning all 1's means that the underlying
device has invalidated the access to the PQ state of the interrupt
through mmio. It may happen, for example when querying a PHB interrupt
while the PHB is in an error state.

In that case, we should consider the interrupt to be invalid when
checking its state in the irq_get_irqchip_state() handler.

Fixes: da15c03b04 ("powerpc/xive: Implement get_irqchip_state method for XIVE to fix shutdown race")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
[clg: wrote a commit log, introduced XIVE_ESB_INVALID ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200113130118.27969-1-clg@kaod.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29 16:45:26 +01:00
Aneesh Kumar K.V 6145307fa6 powerpc/mm/hash: Fix sharing context ids between kernel & userspace
commit 5d2e5dd584 upstream.

Commit 0034d395f8 ("powerpc/mm/hash64: Map all the kernel regions in
the same 0xc range") has a bug in the definition of MIN_USER_CONTEXT.

The result is that the context id used for the vmemmap and the lowest
context id handed out to userspace are the same. The context id is
essentially the process identifier as far as the first stage of the
MMU translation is concerned.

This can result in multiple SLB entries with the same VSID (Virtual
Segment ID), accessible to the kernel and some random userspace
process that happens to get the overlapping id, which is not expected
eg:

  07 c00c000008000000 40066bdea7000500  1T  ESID=   c00c00  VSID=      66bdea7 LLP:100
  12 0002000008000000 40066bdea7000d80  1T  ESID=      200  VSID=      66bdea7 LLP:100

Even though the user process and the kernel use the same VSID, the
permissions in the hash page table prevent the user process from
reading or writing to any kernel mappings.

It can also lead to SLB entries with different base page size
encodings (LLP), eg:

  05 c00c000008000000 00006bde0053b500 256M ESID=c00c00000  VSID=    6bde0053b LLP:100
  09 0000000008000000 00006bde0053bc80 256M ESID=        0  VSID=    6bde0053b LLP:  0

Such SLB entries can result in machine checks, eg. as seen on a G5:

  Oops: Machine check, sig: 7 [#1]
  BE PAGE SIZE=64K MU-Hash SMP NR_CPUS=4 NUMA Power Mac
  NIP: c00000000026f248 LR: c000000000295e58 CTR: 0000000000000000
  REGS: c0000000erfd3d70 TRAP: 0200 Tainted: G M (5.5.0-rcl-gcc-8.2.0-00010-g228b667d8ea1)
  MSR: 9000000000109032 <SF,HV,EE,ME,IR,DR,RI> CR: 24282048 XER: 00000000
  DAR: c00c000000612c80 DSISR: 00000400 IRQMASK: 0
  ...
  NIP [c00000000026f248] .kmem_cache_free+0x58/0x140
  LR  [c088000008295e58] .putname 8x88/0xa
  Call Trace:
    .putname+0xB8/0xa
    .filename_lookup.part.76+0xbe/0x160
    .do_faccessat+0xe0/0x380
    system_call+0x5c/ex68

This happens with 256MB segments and 64K pages, as the duplicate VSID
is hit with the first vmemmap segment and the first user segment, and
older 32-bit userspace maps things in the first user segment.

On other CPUs a machine check is not seen. Instead the userspace
process can get stuck continuously faulting, with the fault never
properly serviced, due to the kernel not understanding that there is
already a HPTE for the address but with inaccessible permissions.

On machines with 1T segments we've not seen the bug hit other than by
deliberately exercising it. That seems to be just a matter of luck
though, due to the typical layout of the user virtual address space
and the ranges of vmemmap that are typically populated.

To fix it we add 2 to MIN_USER_CONTEXT. This ensures the lowest
context given to userspace doesn't overlap with the VMEMMAP context,
or with the context for INVALID_REGION_ID.

Fixes: 0034d395f8 ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Christian Marillat <marillat@debian.org>
Reported-by: Romain Dolbeau <romain@dolbeau.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Account for INVALID_REGION_ID, mostly rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200123102547.11623-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29 16:45:26 +01:00
Ard Biesheuvel 81c13f3897 powerpc/archrandom: fix arch_get_random_seed_int()
commit b6afd1234c upstream.

Commit 01c9348c76

  powerpc: Use hardware RNG for arch_get_random_seed_* not arch_get_random_*

updated arch_get_random_[int|long]() to be NOPs, and moved the hardware
RNG backing to arch_get_random_seed_[int|long]() instead. However, it
failed to take into account that arch_get_random_int() was implemented
in terms of arch_get_random_long(), and so we ended up with a version
of the former that is essentially a NOP as well.

Fix this by calling arch_get_random_seed_long() from
arch_get_random_seed_int() instead.

Fixes: 01c9348c76 ("powerpc: Use hardware RNG for arch_get_random_seed_* not arch_get_random_*")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191204115015.18015-1-ardb@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-26 10:01:00 +01:00
Christophe Leroy 618e593b09 powerpc/kasan: Fix boot failure with RELOCATABLE && FSL_BOOKE
commit 71eb40fc53 upstream.

When enabling CONFIG_RELOCATABLE and CONFIG_KASAN on FSL_BOOKE,
the kernel doesn't boot.

relocate_init() requires KASAN early shadow area to be set up because
it needs access to the device tree through generic functions.

Call kasan_early_init() before calling relocate_init()

Reported-by: Lexi Shao <shaolexi@huawei.com>
Fixes: 2edb16efc8 ("powerpc/32: Add KASAN support")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b58426f1664a4b344ff696d18cacf3b3e8962111.1575036985.git.christophe.leroy@c-s.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-26 10:00:59 +01:00
Tyrel Datwyler 0254daa0ae powerpc/pseries: Enable support for ibm,drc-info property
commit 0a87ccd369 upstream.

Advertise client support for the PAPR architected ibm,drc-info device
tree property during CAS handshake.

Fixes: c7a3275e0f ("powerpc/pseries: Revert support for ibm,drc-info devtree property")
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1573449697-5448-11-git-send-email-tyreld@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-26 10:00:59 +01:00
Geert Uytterhoeven d5c4594b20 powerpc/security: Fix debugfs data leak on 32-bit
commit 3b05a1e517 upstream.

"powerpc_security_features" is "unsigned long", i.e. 32-bit or 64-bit,
depending on the platform (PPC_FSL_BOOK3E or PPC_BOOK3S_64).  Hence
casting its address to "u64 *", and calling debugfs_create_x64() is
wrong, and leaks 32-bit of nearby data to userspace on 32-bit platforms.

While all currently defined SEC_FTR_* security feature flags fit in
32-bit, they all have "ULL" suffixes to make them 64-bit constants.
Hence fix the leak by changing the type of "powerpc_security_features"
(and the parameter types of its accessors) to "u64".  This also allows
to drop the cast.

Fixes: 398af57112 ("powerpc/security: Show powerpc_security_features in debugfs")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191021142309.28105-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-26 10:00:59 +01:00
Oliver O'Halloran 2264fcac85 powerpc/powernv: Disable native PCIe port management
commit 9d72dcef89 upstream.

On PowerNV the PCIe topology is (currently) managed by the powernv platform
code in Linux in cooperation with the platform firmware. Linux's native
PCIe port service drivers operate independently of both and this can cause
problems.

The main issue is that the portbus driver will conflict with the platform
specific hotplug driver (pnv_php) over ownership of the MSI used to notify
the host when a hotplug event occurs. The portbus driver claims this MSI on
behalf of the individual port services because the same interrupt is used
for hotplug events, PMEs (on root ports), and link bandwidth change
notifications. The portbus driver will always claim the interrupt even if
the individual port service drivers, such as pciehp, are compiled out.

The second, bigger, problem is that the hotplug port service driver
fundamentally does not work on PowerNV. The platform assumes that all
PCI devices have a corresponding arch-specific handle derived from the DT
node for the device (pci_dn) and without one the platform will not allow
a PCI device to be enabled. This problem is largely due to historical
baggage, but it can't be resolved without significant re-factoring of the
platform PCI support.

We can fix these problems in the interim by setting the
"pcie_ports_disabled" flag during platform initialisation. The flag
indicates the platform owns the PCIe ports which stops the portbus driver
from being registered.

This does have the side effect of disabling all port services drivers
that is: AER, PME, BW notifications, hotplug, and DPC. However, this is
not a huge disadvantage on PowerNV since these services are either unused
or handled through other means.

Fixes: 66725152fb ("PCI/hotplug: PowerPC PowerNV PCI hotplug driver")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191118065553.30362-1-oohall@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17 19:48:54 +01:00
Jason A. Donenfeld a7ed0553b7 powerpc/spinlocks: Include correct header for static key
commit 6da3eced8c upstream.

Recently, the spinlock implementation grew a static key optimization,
but the jump_label.h header include was left out, leading to build
errors:

  linux/arch/powerpc/include/asm/spinlock.h:44:7: error: implicit declaration of function ‘static_branch_unlikely’
   44 |  if (!static_branch_unlikely(&shared_processor))

This commit adds the missing header.

mpe: The build break is only seen with CONFIG_JUMP_LABEL=n.

Fixes: 656c21d6af ("powerpc/shared: Use static key to detect shared processor")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191223133147.129983-1-Jason@zx2c4.com
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-12 12:21:29 +01:00
Srikar Dronamraju 1e8a2bfed0 powerpc/vcpu: Assume dedicated processors as non-preempt
commit 14c73bd344 upstream.

With commit 247f2f6f3c ("sched/core: Don't schedule threads on
pre-empted vCPUs"), the scheduler avoids preempted vCPUs to schedule
tasks on wakeup. This leads to wrong choice of CPU, which in-turn
leads to larger wakeup latencies. Eventually, it leads to performance
regression in latency sensitive benchmarks like soltp, schbench etc.

On Powerpc, vcpu_is_preempted() only looks at yield_count. If the
yield_count is odd, the vCPU is assumed to be preempted. However
yield_count is increased whenever the LPAR enters CEDE state (idle).
So any CPU that has entered CEDE state is assumed to be preempted.

Even if vCPU of dedicated LPAR is preempted/donated, it should have
right of first-use since they are supposed to own the vCPU.

On a Power9 System with 32 cores:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              128
  On-line CPU(s) list: 0-127
  Thread(s) per core:  8
  Core(s) per socket:  1
  Socket(s):           16
  NUMA node(s):        2
  Model:               2.2 (pvr 004e 0202)
  Model name:          POWER9 (architected), altivec supported
  Hypervisor vendor:   pHyp
  Virtualization type: para
  L1d cache:           32K
  L1i cache:           32K
  L2 cache:            512K
  L3 cache:            10240K
  NUMA node0 CPU(s):   0-63
  NUMA node1 CPU(s):   64-127

  # perf stat -a -r 5 ./schbench
  v5.4                               v5.4 + patch
  Latency percentiles (usec)         Latency percentiles (usec)
        50.0000th: 45                      50.0th: 45
        75.0000th: 62                      75.0th: 63
        90.0000th: 71                      90.0th: 74
        95.0000th: 77                      95.0th: 78
        *99.0000th: 91                     *99.0th: 82
        99.5000th: 707                     99.5th: 83
        99.9000th: 6920                    99.9th: 86
        min=0, max=10048                   min=0, max=96
  Latency percentiles (usec)         Latency percentiles (usec)
        50.0000th: 45                      50.0th: 46
        75.0000th: 61                      75.0th: 64
        90.0000th: 72                      90.0th: 75
        95.0000th: 79                      95.0th: 79
        *99.0000th: 691                    *99.0th: 83
        99.5000th: 3972                    99.5th: 85
        99.9000th: 8368                    99.9th: 91
        min=0, max=16606                   min=0, max=117
  Latency percentiles (usec)         Latency percentiles (usec)
        50.0000th: 45                      50.0th: 46
        75.0000th: 61                      75.0th: 64
        90.0000th: 71                      90.0th: 75
        95.0000th: 77                      95.0th: 79
        *99.0000th: 106                    *99.0th: 83
        99.5000th: 2364                    99.5th: 84
        99.9000th: 7480                    99.9th: 90
        min=0, max=10001                   min=0, max=95
  Latency percentiles (usec)         Latency percentiles (usec)
        50.0000th: 45                      50.0th: 47
        75.0000th: 62                      75.0th: 65
        90.0000th: 72                      90.0th: 75
        95.0000th: 78                      95.0th: 79
        *99.0000th: 93                     *99.0th: 84
        99.5000th: 108                     99.5th: 85
        99.9000th: 6792                    99.9th: 90
        min=0, max=17681                   min=0, max=117
  Latency percentiles (usec)         Latency percentiles (usec)
        50.0000th: 46                      50.0th: 45
        75.0000th: 62                      75.0th: 64
        90.0000th: 73                      90.0th: 75
        95.0000th: 79                      95.0th: 79
        *99.0000th: 113                    *99.0th: 82
        99.5000th: 2724                    99.5th: 83
        99.9000th: 6184                    99.9th: 93
        min=0, max=9887                    min=0, max=111

   Performance counter stats for 'system wide' (5 runs):

  context-switches    43,373  ( +-  0.40% )   44,597 ( +-  0.55% )
  cpu-migrations       1,211  ( +-  5.04% )      220 ( +-  6.23% )
  page-faults         15,983  ( +-  5.21% )   15,360 ( +-  3.38% )

Waiman Long suggested using static_keys.

Fixes: 247f2f6f3c ("sched/core: Don't schedule threads on pre-empted vCPUs")
Cc: stable@vger.kernel.org # v4.18+
Reported-by: Parth Shah <parth@linux.ibm.com>
Reported-by: Ihor Pasichnyk <Ihor.Pasichnyk@ibm.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Acked-by: Waiman Long <longman@redhat.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Tested-by: Parth Shah <parth@linux.ibm.com>
[mpe: Move the key and setting of the key to pseries/setup.c]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191213035036.6913-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-12 12:21:29 +01:00
Mike Rapoport 673e43cf49 powerpc: Ensure that swiotlb buffer is allocated from low memory
[ Upstream commit 8fabc62323 ]

Some powerpc platforms (e.g. 85xx) limit DMA-able memory way below 4G.
If a system has more physical memory than this limit, the swiotlb
buffer is not addressable because it is allocated from memblock using
top-down mode.

Force memblock to bottom-up mode before calling swiotlb_init() to
ensure that the swiotlb buffer is DMA-able.

Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191204123524.22919-1-rppt@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-12 12:21:28 +01:00
Aneesh Kumar K.V d7742abfe6 powerpc/pmem: Fix kernel crash due to wrong range value usage in flush_dcache_range
commit 6f4679b956 upstream.

This patch fix the below kernel crash.

 BUG: Unable to handle kernel data access on read at 0xc000000380000000
 Faulting instruction address: 0xc00000000008b6f0
cpu 0x5: Vector: 300 (Data Access) at [c0000000d8587790]
    pc: c00000000008b6f0: arch_remove_memory+0x150/0x210
    lr: c00000000008b720: arch_remove_memory+0x180/0x210
    sp: c0000000d8587a20
   msr: 800000000280b033
   dar: c000000380000000
 dsisr: 40000000
  current = 0xc0000000d8558600
  paca    = 0xc00000000fff8f00   irqmask: 0x03   irq_happened: 0x01
    pid   = 1220, comm = ndctl
enter ? for help
 memunmap_pages+0x33c/0x410
 devm_action_release+0x30/0x50
 release_nodes+0x30c/0x3a0
 device_release_driver_internal+0x178/0x240
 unbind_store+0x74/0x190
 drv_attr_store+0x44/0x60
 sysfs_kf_write+0x74/0xa0
 kernfs_fop_write+0x1b0/0x260
 __vfs_write+0x3c/0x70
 vfs_write+0xe4/0x200
 ksys_write+0x7c/0x140
 system_call+0x5c/0x68

Fixes: 076265907c ("powerpc: Chunk calls to flush_dcache_range in arch_*_memory")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191204052909.59145-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09 10:25:53 +01:00
Michael Ellerman 2fb97a8e25 powerpc/mm: Mark get_slice_psize() & slice_addr_is_low() as notrace
commit 91a063c956 upstream.

These slice routines are called from the SLB miss handler, which can
lead to warnings from the IRQ code, because we have not reconciled the
IRQ state properly:

  WARNING: CPU: 72 PID: 30150 at arch/powerpc/kernel/irq.c:258 arch_local_irq_restore.part.0+0xcc/0x100
  Modules linked in:
  CPU: 72 PID: 30150 Comm: ftracetest Not tainted 5.5.0-rc2-gcc9x-g7e0165b2f1a9 #1
  NIP:  c00000000001d83c LR: c00000000029ab90 CTR: c00000000026cf90
  REGS: c0000007eee3b960 TRAP: 0700   Not tainted  (5.5.0-rc2-gcc9x-g7e0165b2f1a9)
  MSR:  8000000000021033 <SF,ME,IR,DR,RI,LE>  CR: 22242844  XER: 20000000
  CFAR: c00000000001d780 IRQMASK: 0
  ...
  NIP arch_local_irq_restore.part.0+0xcc/0x100
  LR  trace_graph_entry+0x270/0x340
  Call Trace:
    trace_graph_entry+0x254/0x340 (unreliable)
    function_graph_enter+0xe4/0x1a0
    prepare_ftrace_return+0xa0/0x130
    ftrace_graph_caller+0x44/0x94	# (get_slice_psize())
    slb_allocate_user+0x7c/0x100
    do_slb_fault+0xf8/0x300
    instruction_access_slb_common+0x140/0x180

Fixes: 48e7b76957 ("powerpc/64s/hash: Convert SLB miss handlers to C")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191221121337.4894-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09 10:20:04 +01:00
Alastair D'Silva 0e9d2e5f71 powerpc: Chunk calls to flush_dcache_range in arch_*_memory
commit 076265907c upstream.

When presented with large amounts of memory being hotplugged
(in my test case, ~890GB), the call to flush_dcache_range takes
a while (~50 seconds), triggering RCU stalls.

This patch breaks up the call into 1GB chunks, calling
cond_resched() inbetween to allow the scheduler to run.

Fixes: fb5924fddf ("powerpc/mm: Flush cache on memory hot(un)plug")
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191104023305.9581-6-alastair@au1.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09 10:20:02 +01:00
David Hildenbrand e84c5b7617 mm/memory_hotplug: shrink zones when offlining memory
commit feee6b2989 upstream.

We currently try to shrink a single zone when removing memory.  We use
the zone of the first page of the memory we are removing.  If that
memmap was never initialized (e.g., memory was never onlined), we will
read garbage and can trigger kernel BUGs (due to a stale pointer):

    BUG: unable to handle page fault for address: 000000000000353d
    #PF: supervisor write access in kernel mode
    #PF: error_code(0x0002) - not-present page
    PGD 0 P4D 0
    Oops: 0002 [#1] SMP PTI
    CPU: 1 PID: 7 Comm: kworker/u8:0 Not tainted 5.3.0-rc5-next-20190820+ #317
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.4
    Workqueue: kacpi_hotplug acpi_hotplug_work_fn
    RIP: 0010:clear_zone_contiguous+0x5/0x10
    Code: 48 89 c6 48 89 c3 e8 2a fe ff ff 48 85 c0 75 cf 5b 5d c3 c6 85 fd 05 00 00 01 5b 5d c3 0f 1f 840
    RSP: 0018:ffffad2400043c98 EFLAGS: 00010246
    RAX: 0000000000000000 RBX: 0000000200000000 RCX: 0000000000000000
    RDX: 0000000000200000 RSI: 0000000000140000 RDI: 0000000000002f40
    RBP: 0000000140000000 R08: 0000000000000000 R09: 0000000000000001
    R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000140000
    R13: 0000000000140000 R14: 0000000000002f40 R15: ffff9e3e7aff3680
    FS:  0000000000000000(0000) GS:ffff9e3e7bb00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 000000000000353d CR3: 0000000058610000 CR4: 00000000000006e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     __remove_pages+0x4b/0x640
     arch_remove_memory+0x63/0x8d
     try_remove_memory+0xdb/0x130
     __remove_memory+0xa/0x11
     acpi_memory_device_remove+0x70/0x100
     acpi_bus_trim+0x55/0x90
     acpi_device_hotplug+0x227/0x3a0
     acpi_hotplug_work_fn+0x1a/0x30
     process_one_work+0x221/0x550
     worker_thread+0x50/0x3b0
     kthread+0x105/0x140
     ret_from_fork+0x3a/0x50
    Modules linked in:
    CR2: 000000000000353d

Instead, shrink the zones when offlining memory or when onlining failed.
Introduce and use remove_pfn_range_from_zone(() for that.  We now
properly shrink the zones, even if we have DIMMs whereby

 - Some memory blocks fall into no zone (never onlined)

 - Some memory blocks fall into multiple zones (offlined+re-onlined)

 - Multiple memory blocks that fall into different zones

Drop the zone parameter (with a potential dubious value) from
__remove_pages() and __remove_section().

Link: http://lkml.kernel.org/r/20191006085646.5768-6-david@redhat.com
Fixes: f1dd2cd13c ("mm, memory_hotplug: do not associate hotadded memory to zones until online")	[visible after d0dc12e86b]
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: <stable@vger.kernel.org>	[5.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09 10:19:56 +01:00
Andrew Donnellan e83c40f7bb powerpc: Fix __clear_user() with KUAP enabled
commit 61e3acd8c6 upstream.

The KUAP implementation adds calls in clear_user() to enable and
disable access to userspace memory. However, it doesn't add these to
__clear_user(), which is used in the ptrace regset code.

As there's only one direct user of __clear_user() (the regset code),
and the time taken to set the AMR for KUAP purposes is going to
dominate the cost of a quick access_ok(), there's not much point
having a separate path.

Rename __clear_user() to __arch_clear_user(), and make __clear_user()
just call clear_user().

Reported-by: syzbot+f25ecf4b2982d8c7a640@syzkaller-ppc64.appspotmail.com
Reported-by: Daniel Axtens <dja@axtens.net>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: de78a9c42a ("powerpc: Add a framework for Kernel Userspace Access Protection")
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
[mpe: Use __arch_clear_user() for the asm version like arm64 & nds32]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191209132221.15328-1-ajd@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04 19:18:37 +01:00
Greg Kroah-Hartman f36b4556e5 Revert "powerpc/vcpu: Assume dedicated processors as non-preempt"
This reverts commit 8332dbe515 which is
commit 14c73bd344 upstream.

It breaks the build.

Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Parth Shah <parth@linux.ibm.com>
Cc: Ihor Pasichnyk <Ihor.Pasichnyk@ibm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Cc: Parth Shah <parth@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04 19:18:33 +01:00