Commit e6023367d7 ("x86, kaslr: Prevent .bss from overlaping initrd")
added Perl to the required build environment. This reimplements in
shell the Perl script used to find the size of the kernel with bss and
brk added.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Rob Landley <rob@landley.net>
Acked-by: Rob Landley <rob@landley.net>
Cc: Anca Emanuel <anca.emanuel@gmail.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On 64-bit, relocation is not required unless the load address gets
changed. Without this, relocations do unexpected things when the kernel
is above 4G.
Reported-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Thomas D. <whissi@whissi.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20150116005146.GA4212@www.outflux.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Commit 9def39be4e ("x86: Support compiling out human-friendly
processor feature names") made two source file targets
conditional. Such conditional targets will not be cleaned
automatically by make mrproper.
Fix by adding explicit clean-files targets for the two files.
Fixes: 9def39be4e ("x86: Support compiling out human-friendly processor feature names")
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Cc: Josh Triplett <josh@joshtriplett.org>
Link: http://lkml.kernel.org/r/1419335863-10608-1-git-send-email-bjorn@mork.no
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull EFI updates from Ingo Molnar:
"Changes in this cycle are:
- support module unload for efivarfs (Mathias Krause)
- another attempt at moving x86 to libstub taking advantage of the
__pure attribute (Ard Biesheuvel)
- add EFI runtime services section to ptdump (Mathias Krause)"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, ptdump: Add section for EFI runtime services
efi/x86: Move x86 back to libstub
efivarfs: Allow unloading when build as module
Pull x86 boot and percpu updates from Ingo Molnar:
"This tree contains a bootable images documentation update plus three
slightly misplaced x86/asm percpu changes/optimizations"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86-64: Use RIP-relative addressing for most per-CPU accesses
x86-64: Handle PC-relative relocations on per-CPU data
x86: Convert a few more per-CPU items to read-mostly ones
x86, boot: Document intermediates more clearly
commit e6023367d7 'x86, kaslr: Prevent .bss from overlaping initrd'
broke the cross compile of x86. It added a objdump invocation, which
invokes the host native objdump and ignores an active cross tool
chain.
Use $(OBJDUMP) instead which takes the CROSS_COMPILE prefix into
account.
[ tglx: Massage changelog and use $(OBJDUMP) ]
Fixes: e6023367d7 'x86, kaslr: Prevent .bss from overlaping initrd'
Signed-off-by: Chris Clayton <chris2553@googlemail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/54705C8E.1080400@googlemail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This reverts commit 84be880560, which itself reverted my original
attempt to move x86 from #include'ing .c files from across the tree
to using the EFI stub built as a static library.
The issue that affected the original approach was that splitting
the implementation into several .o files resulted in the variable
'efi_early' becoming a global with external linkage, which under
-fPIC implies that references to it must go through the GOT. However,
dealing with this additional GOT entry turned out to be troublesome
on some EFI implementations. (GCC's visibility=hidden attribute is
supposed to lift this requirement, but it turned out not to work on
the 32-bit build.)
Instead, use a pure getter function to get a reference to efi_early.
This approach results in no additional GOT entries being generated,
so there is no need for any changes in the early GOT handling.
Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This adds a comment detailing the various intermediate files used to build
the bootable decompression image for the x86 kernel.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Link: http://lkml.kernel.org/r/20141031162204.GA26268@www.outflux.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When choosing a random address, the current implementation does not take into
account the reversed space for .bss and .brk sections. Thus the relocated kernel
may overlap other components in memory. Here is an example of the overlap from a
x86_64 kernel in qemu (the ranges of physical addresses are presented):
Physical Address
0x0fe00000 --+--------------------+ <-- randomized base
/ | relocated kernel |
vmlinux.bin | (from vmlinux.bin) |
0x1336d000 (an ELF file) +--------------------+--
\ | | \
0x1376d870 --+--------------------+ |
| relocs table | |
0x13c1c2a8 +--------------------+ .bss and .brk
| | |
0x13ce6000 +--------------------+ |
| | /
0x13f77000 | initrd |--
| |
0x13fef374 +--------------------+
The initrd image will then be overwritten by the memset during early
initialization:
[ 1.655204] Unpacking initramfs...
[ 1.662831] Initramfs unpacking failed: junk in compressed archive
This patch prevents the above situation by requiring a larger space when looking
for a random kernel base, so that existing logic can effectively avoids the
overlap.
[kees: switched to perl to avoid hex translation pain in mawk vs gawk]
[kees: calculated overlap without relocs table]
Fixes: 82fa9637a2 ("x86, kaslr: Select random position from e820 maps")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Junjie Mao <eternal.n08@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1414762838-13067-1-git-send-email-eternal.n08@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull x86 EFI updates from Peter Anvin:
"This patchset falls under the "maintainers that grovel" clause in the
v3.18-rc1 announcement. We had intended to push it late in the merge
window since we got it into the -tip tree relatively late.
Many of these are relatively simple things, but there are a couple of
key bits, especially Ard's and Matt's patches"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
rtc: Disable EFI rtc for x86
efi: rtc-efi: Export platform:rtc-efi as module alias
efi: Delete the in_nmi() conditional runtime locking
efi: Provide a non-blocking SetVariable() operation
x86/efi: Adding efi_printks on memory allocationa and pci.reads
x86/efi: Mark initialization code as such
x86/efi: Update comment regarding required phys mapped EFI services
x86/efi: Unexport add_efi_memmap variable
x86/efi: Remove unused efi_call* macros
efi: Resolve some shadow warnings
arm64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
ia64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
x86: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
efi: Introduce efi_md_typeattr_format()
efi: Add macro for EFI_MEMORY_UCE memory attribute
x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode
arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi
arm64/efi: uefi_init error handling fix
efi: Add kernel param efi=noruntime
lib: Add a generic cmdline parse function parse_option_str
...
Pull x86 fixes from Ingo Molnar:
"Misc smaller fixes that missed the v3.17 cycle"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/build: Add arch/x86/purgatory/ make generated files to gitignore
x86: Fix section conflict for numachip
x86: Reject x32 executables if x32 ABI not supported
x86_64, entry: Filter RFLAGS.NT on entry from userspace
x86, boot, kaslr: Fix nuisance warning on 32-bit builds
Pull x86 cpufeature updates from Ingo Molnar:
"This tree includes the following changes:
- Introduce DISABLED_MASK to list disabled CPU features, to simplify
CPU feature handling and avoid excessive #ifdefs
- Remove the lightly used cpu_has_pae() primitive"
* 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Add more disabled features
x86: Introduce disabled-features
x86: Axe the lightly-used cpu_has_pae
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Merge tag 'tiny/for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux
Pull "tinification" patches from Josh Triplett.
Work on making smaller kernels.
* tag 'tiny/for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux:
bloat-o-meter: Ignore syscall aliases SyS_ and compat_SyS_
mm: Support compiling out madvise and fadvise
x86: Support compiling out human-friendly processor feature names
x86: Drop support for /proc files when !CONFIG_PROC_FS
x86, boot: Don't compile early_serial_console.c when !CONFIG_EARLY_PRINTK
x86, boot: Don't compile aslr.c when !CONFIG_RANDOMIZE_BASE
x86, boot: Use the usual -y -n mechanism for objects in vmlinux
x86: Add "make tinyconfig" to configure the tiniest possible kernel
x86, platform, kconfig: move kvmconfig functionality to a helper
All other calls to allocate memory seem to make some noise already, with the
exception of two calls (for gop, uga) in the setup_graphics path.
The purpose is to be noisy on worrysome errors immediately.
commit fb86b2440d ("x86/efi: Add better error logging to EFI boot
stub") introduces printing false alarms for lots of hardware. Rather
than playing Whack a Mole with non-fatal exit conditions, try the other
way round.
This is per Matt Fleming's suggestion:
> Where I think we could improve things
> is by adding efi_printk() message in certain error paths. Clearly, not
> all error paths need such messages, e.g. the EFI_INVALID_PARAMETER path
> you highlighted above, but it makes sense for memory allocation and PCI
> read failures.
Link: http://article.gmane.org/gmane.linux.kernel.efi/4628
Signed-off-by: Andre Müller <andre.muller@web.de>
Cc: Ulf Winkelvos <ulf@winkelvos.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
We need a way to customize the behaviour of the EFI boot stub, in
particular, we need a way to disable the "chunking" workaround, used
when reading files from the EFI System Partition.
One of my machines doesn't cope well when reading files in 1MB chunks to
a buffer above the 4GB mark - it appears that the "chunking" bug
workaround triggers another firmware bug. This was only discovered with
commit 4bf7111f50 ("x86/efi: Support initrd loaded above 4G"), and
that commit is perfectly valid. The symptom I observed was a corrupt
initrd rather than any kind of crash.
efi= is now used to specify EFI parameters in two very different
execution environments, the EFI boot stub and during kernel boot.
There is also a slight performance optimization by enabling efi=nochunk,
but that's offset by the fact that you're more likely to run into
firmware issues, at least on x86. This is the rationale behind leaving
the workaround enabled by default.
Also provide some documentation for EFI_READ_CHUNK_SIZE and why we're
using the current value of 1MB.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Roy Franz <roy.franz@linaro.org>
Cc: Maarten Lankhorst <m.b.lankhorst@gmail.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Building 32-bit threw a warning on kASLR enabled builds:
arch/x86/boot/compressed/aslr.c: In function ‘mem_avoid_overlap’:
arch/x86/boot/compressed/aslr.c:198:17: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
avoid.start = (u64)ptr;
^
This fixes the warning; unsigned long should have been used here.
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20141001183632.GA11431@www.outflux.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull x86 fixes from Ingo Molnar:
"This has:
- EFI revert to fix a boot regression
- early_ioremap() fix for boot failure
- KASLR fix for possible boot failures
- EFI fix for corrupted string printing
- remove a misleading EFI bootup 'failed!' error message
Unfortunately it's all rather close to the merge window"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Truncate 64-bit values when calling 32-bit OutputString()
x86/efi: Delete misleading efi_printk() error message
Revert "efi/x86: efistub: Move shared dependencies to <asm/efi.h>"
x86/kaslr: Avoid the setup_data area when picking location
x86 early_ioremap: Increase FIX_BTMAPS_SLOTS to 8
causing issues for Macbooks and Fedora + Grub2 - Matt Fleming
* Delete the misleading "setup_efi_pci() failed!" message which some
people are seeing when booting EFI - Matt Fleming
* Fix printing strings from the 32-bit EFI boot stub by only passing
32-bit addresses to the firmware - Matt Fleming
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Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent
Pull EFI fixes from Matt Fleming:
* Revert the static library changes from the merge window since they're
causing issues for Macbooks and Fedora + Grub2 (Matt Fleming)
* Delete the misleading "setup_efi_pci() failed!" message which some
people are seeing when booting EFI (Matt Fleming)
* Fix printing strings from the 32-bit EFI boot stub by only passing
32-bit addresses to the firmware (Matt Fleming)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If we're executing the 32-bit efi_char16_printk() code path (i.e.
running on top of 32-bit firmware) we know that efi_early->text_output
will be a 32-bit value, even though ->text_output has type u64.
Unfortunately, we currently pass ->text_output directly to
efi_early->call() so for CONFIG_X86_32 the compiler will push a 64-bit
value onto the stack, causing the other parameters to be misaligned.
The way we handle this in the rest of the EFI boot stub is to pass
pointers as arguments to efi_early->call(), which automatically do the
right thing (pointers are 32-bit on CONFIG_X86_32, and we simply ignore
the upper 32-bits of the argument register if running in 64-bit mode
with 32-bit firmware).
This fixes a corruption bug when printing strings from the 32-bit EFI
boot stub.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=84241
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
A number of people are reporting seeing the "setup_efi_pci() failed!"
error message in what used to be a quiet boot,
https://bugzilla.kernel.org/show_bug.cgi?id=81891
The message isn't all that helpful because setup_efi_pci() can return a
non-success error code for a variety of reasons, not all of them fatal.
Let's drop the return code from setup_efi_pci*() altogether, since
there's no way to process it in any meaningful way outside of the inner
__setup_efi_pci*() functions.
Reported-by: Darren Hart <dvhart@linux.intel.com>
Reported-by: Josh Boyer <jwboyer@fedoraproject.org>
Cc: Ulf Winkelvos <ulf@winkelvos.de>
Cc: Andre Müller <andre.muller@web.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This reverts commit f23cf8bd5c ("efi/x86: efistub: Move shared
dependencies to <asm/efi.h>") as well as the x86 parts of commit
f4f75ad574 ("efi: efistub: Convert into static library").
The road leading to these two reverts is long and winding.
The above two commits were merged during the v3.17 merge window and
turned the common EFI boot stub code into a static library. This
necessitated making some symbols global in the x86 boot stub which
introduced new entries into the early boot GOT.
The problem was that we weren't fixing up the newly created GOT entries
before invoking the EFI boot stub, which sometimes resulted in hangs or
resets. This failure was reported by Maarten on his Macbook pro.
The proposed fix was commit 9cb0e39423 ("x86/efi: Fixup GOT in all
boot code paths"). However, that caused issues for Linus when booting
his Sony Vaio Pro 11. It was subsequently reverted in commit
f3670394c2.
So that leaves us back with Maarten's Macbook pro not booting.
At this stage in the release cycle the least risky option is to revert
the x86 EFI boot stub to the pre-merge window code structure where we
explicitly #include efi-stub-helper.c instead of linking with the static
library. The arm64 code remains unaffected.
We can take another swing at the x86 parts for v3.18.
Conflicts:
arch/x86/include/asm/efi.h
Tested-by: Josh Boyer <jwboyer@fedoraproject.org>
Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org> [arm64]
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This reverts commit 9cb0e39423.
It causes my Sony Vaio Pro 11 to immediately reboot at startup.
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The KASLR location-choosing logic needs to avoid the setup_data
list memory areas as well. Without this, it would be possible to
have the ASLR position stomp on the memory, ultimately causing
the boot to fail.
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Baoquan He <bhe@redhat.com>
Cc: stable@vger.kernel.org
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140911161931.GA12001@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I believe the REQUIRED_MASK aproach was taken so that it was
easier to consult in assembly (arch/x86/kernel/verify_cpu.S).
DISABLED_MASK does not have the same restriction, but I
implemented it the same way for consistency.
We have a REQUIRED_MASK... which does two things:
1. Keeps a list of cpuid bits to check in very early boot and
refuse to boot if those are not present.
2. Consulted during cpu_has() checks, which allows us to
optimize out things at compile-time. In other words, if we
*KNOW* we will not boot with the feature off, then we can
safely assume that it will be present forever.
But, we don't have a similar mechanism for CPU features which
may be present but that we know we will not use. We simply
use our existing mechanisms to repeatedly check the status of
the bit at runtime (well, the alternatives patching helps here
but it does not provide compile-time optimization).
Adding a feature to disabled-features.h allows the bit to be
checked via a new macro: cpu_feature_enabled(). Note that
for features in DISABLED_MASK, checks with this macro have
all of the benefits of an #ifdef. Before, we would have done
this in a header:
#ifdef CONFIG_X86_INTEL_MPX
#define cpu_has_mpx cpu_has(X86_FEATURE_MPX)
#else
#define cpu_has_mpx 0
#endif
and this in the code:
if (cpu_has_mpx)
do_some_mpx_thing();
Now, just add your feature to DISABLED_MASK and you can do this
everywhere, and get the same benefits you would have from
#ifdefs:
if (cpu_feature_enabled(X86_FEATURE_MPX))
do_some_mpx_thing();
We need a new function and *not* a modification to cpu_has()
because there are cases where we actually need to check the CPU
itself, despite what features the kernel supports. The best
example of this is a hypervisor which has no control over what
features its guests are using and where the guest does not depend
on the host for support.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140911211513.9E35E931@viggo.jf.intel.com
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Maarten reported that his Macbook pro 8.2 stopped booting after commit
f23cf8bd5c ("efi/x86: efistub: Move shared dependencies to
<asm/efi.h>"), the main feature of which is changing the visibility of
symbol 'efi_early' from local to global.
By making 'efi_early' global we end up requiring an entry in the Global
Offset Table. Unfortunately, while we do include code to fixup GOT
entries in the early boot code, it's only called after we've executed
the EFI boot stub.
What this amounts to is that references to 'efi_early' in the EFI boot
stub don't point to the correct place.
Since we've got multiple boot entry points we need to be prepared to
fixup the GOT in multiple places, while ensuring that we never do it
more than once, otherwise the GOT entries will still point to the wrong
place.
Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Mantas found that after commit 4bf7111f50 ("x86/efi: Support initrd
loaded above 4G"), the kernel freezes at the earliest possible moment
when trying to boot via UEFI on Asus laptop.
Revert to old way to load initrd under 4G on first try, second try will
use above 4G buffer when initrd is too big and does not fit under 4G.
[ The cause of the freeze appears to be a firmware bug when reading
file data into buffers above 4GB, though the exact reason is unknown.
Mantas reports that the hang can be avoid if the file size is a
multiple of 512 bytes, but I've seen some ASUS firmware simply
corrupting the file data rather than freezing.
Laszlo fixed an issue in the upstream EDK2 DiskIO code in Aug 2013
which may possibly be related, commit 4e39b75e ("MdeModulePkg/DiskIoDxe:
fix source/destination pointer of overrun transfer").
Whatever the cause, it's unlikely that a fix will be forthcoming
from the vendor, hence the workaround - Matt ]
Cc: Laszlo Ersek <lersek@redhat.com>
Reported-by: Mantas Mikulėnas <grawity@gmail.com>
Reported-by: Harald Hoyer <harald@redhat.com>
Tested-by: Anders Darander <anders@chargestorm.se>
Tested-by: Calvin Walton <calvin.walton@kepstin.ca>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
The table mapping CPUID bits to human-readable strings takes up a
non-trivial amount of space, and only exists to support /proc/cpuinfo
and a couple of kernel messages. Since programs depend on the format of
/proc/cpuinfo, force inclusion of the table when building with /proc
support; otherwise, support omitting that table to save space, in which
case the kernel messages will print features numerically instead.
In addition to saving 1408 bytes out of vmlinux, this also saves 1373
bytes out of the uncompressed setup code, which contributes directly to
the size of bzImage.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
All the code in early_serial_console.c gets compiled out if
!CONFIG_EARLY_PRINTK, but early_serial_console.o itself still gets
compiled in. Eliminate it from the compile entirely in that case.
This does not change the generated code at all, in either case.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
All the code in aslr.c gets compiled out if !CONFIG_RANDOMIZE_BASE, but
aslr.o itself still gets compiled in. Eliminate it from the compile
entirely in that case.
This does not change the generated code at all, in either case.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Switch VMLINUX_OBJS to vmlinux-objs-y, to eliminate Makefile
conditionals in favor of vmlinux-objs-$(CONFIG_*) constructs.
This does not change the generated code at all.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Pull EFI changes from Ingo Molnar:
"Main changes in this cycle are:
- arm64 efi stub fixes, preservation of FP/SIMD registers across
firmware calls, and conversion of the EFI stub code into a static
library - Ard Biesheuvel
- Xen EFI support - Daniel Kiper
- Support for autoloading the efivars driver - Lee, Chun-Yi
- Use the PE/COFF headers in the x86 EFI boot stub to request that
the stub be loaded with CONFIG_PHYSICAL_ALIGN alignment - Michael
Brown
- Consolidate all the x86 EFI quirks into one file - Saurabh Tangri
- Additional error logging in x86 EFI boot stub - Ulf Winkelvos
- Support loading initrd above 4G in EFI boot stub - Yinghai Lu
- EFI reboot patches for ACPI hardware reduced platforms"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
efi/arm64: Handle missing virtual mapping for UEFI System Table
arch/x86/xen: Silence compiler warnings
xen: Silence compiler warnings
x86/efi: Request desired alignment via the PE/COFF headers
x86/efi: Add better error logging to EFI boot stub
efi: Autoload efivars
efi: Update stale locking comment for struct efivars
arch/x86: Remove efi_set_rtc_mmss()
arch/x86: Replace plain strings with constants
xen: Put EFI machinery in place
xen: Define EFI related stuff
arch/x86: Remove redundant set_bit(EFI_MEMMAP) call
arch/x86: Remove redundant set_bit(EFI_SYSTEM_TABLES) call
efi: Introduce EFI_PARAVIRT flag
arch/x86: Do not access EFI memory map if it is not available
efi: Use early_mem*() instead of early_io*()
arch/ia64: Define early_memunmap()
x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag
efi/reboot: Allow powering off machines using EFI
efi/reboot: Add generic wrapper around EfiResetSystem()
...
Pull x86 build/cleanup/debug updates from Ingo Molnar:
"Robustify the build process with a quirk to avoid GCC reordering
related bugs.
Two code cleanups.
Simplify entry_64.S CFI annotations, by Jan Beulich"
* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, build: Change code16gcc.h from a C header to an assembly header
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Simplify __HAVE_ARCH_CMPXCHG tests
x86/tsc: Get rid of custom DIV_ROUND() macro
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/debug: Drop several unnecessary CFI annotations
The EFI boot stub goes to great pains to relocate the kernel image to
an appropriately aligned address, as indicated by the ->kernel_alignment
field in the bzImage header. However, for the PE stub entry case, we
can request that the EFI PE/COFF loader do the work for us.
Fix by exposing the desired alignment via the SectionAlignment field
in the PE/COFF headers. Despite its name, this field provides an
overall alignment requirement for the loaded file. (Naturally, the
FileAlignment field describes the alignment for individual sections.)
There is no way in the PE/COFF headers to express the concept of
min_alignment; we therefore do not expose the minimum (as opposed to
preferred) alignment.
Signed-off-by: Michael Brown <mbrown@fensystems.co.uk>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Hopefully this will enable us to better debug:
https://bugzilla.kernel.org/show_bug.cgi?id=68761
Signed-off-by: Ulf Winkelvos <ulf@winkelvos.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This patch changes both x86 and arm64 efistub implementations
from #including shared .c files under drivers/firmware/efi to
building shared code as a static library.
The x86 code uses a stub built into the boot executable which
uncompresses the kernel at boot time. In this case, the library is
linked into the decompressor.
In the arm64 case, the stub is part of the kernel proper so the library
is linked into the kernel proper as well.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
which, apart from reducing code duplication also stops the arm64 stub
being rebuilt every time make is invoked - Ard Biesheuvel
* Fix the EFI fdt code to not report a boot error if UEFI is
unavailable since booting without UEFI parameters is a valid use case
for non-UEFI platforms - Catalin Marinas
* Include a .bss section in the EFI boot stub PE/COFF headers to fix a
memory corruption bug - Michael Brown
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Merge tag 'efi-urgent' into x86/urgent
* Remove a duplicate copy of linux_banner from the arm64 EFI stub
which, apart from reducing code duplication also stops the arm64 stub
being rebuilt every time make is invoked - Ard Biesheuvel
* Fix the EFI fdt code to not report a boot error if UEFI is
unavailable since booting without UEFI parameters is a valid use case
for non-UEFI platforms - Catalin Marinas
* Include a .bss section in the EFI boot stub PE/COFF headers to fix a
memory corruption bug - Michael Brown
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The PE/COFF headers currently describe only the initialised-data
portions of the image, and result in no space being allocated for the
uninitialised-data portions. Consequently, the EFI boot stub will end
up overwriting unexpected areas of memory, with unpredictable results.
Fix by including a .bss section in the PE/COFF headers (functionally
equivalent to the init_size field in the bzImage header).
Signed-off-by: Michael Brown <mbrown@fensystems.co.uk>
Cc: Thomas Bächler <thomas@archlinux.org>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
In order to move from the #include "../../../xxxxx.c" anti-pattern used
by both the x86 and arm64 versions of the stub to a static library
linked into either the kernel proper (arm64) or a separate boot
executable (x86), there is some prepatory work required.
This patch does the following:
- move forward declarations of functions shared between the arch
specific and the generic parts of the stub to include/linux/efi.h
- move forward declarations of functions shared between various .c files
of the generic stub code to a new local header file called "efistub.h"
- add #includes to all .c files which were formerly relying on the
#includor to include the correct header files
- remove all static modifiers from functions which will need to be
externally visible once we move to a static library
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This moves definitions depended upon both by code under arch/x86/boot
and under drivers/firmware/efi to <asm/efi.h>. This is in preparation of
turning the stub code under drivers/firmware/efi into a static library.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
For boot efi kernel directly without bootloader.
If the kernel support XLF_CAN_BE_LOADED_ABOVE_4G, we should
not limit initrd under hdr->initrd_add_max.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Changes kASLR from being compile-time selectable (blocked by
CONFIG_HIBERNATION), to being boot-time selectable (with hibernation
available by default) via the "kaslr" kernel command line.
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Now that 3.15 is released, this merges the 'next' branch into 'master',
bringing us to the normal situation where my 'master' branch is the
merge window.
* accumulated work in next: (6809 commits)
ufs: sb mutex merge + mutex_destroy
powerpc: update comments for generic idle conversion
cris: update comments for generic idle conversion
idle: remove cpu_idle() forward declarations
nbd: zero from and len fields in NBD_CMD_DISCONNECT.
mm: convert some level-less printks to pr_*
MAINTAINERS: adi-buildroot-devel is moderated
MAINTAINERS: add linux-api for review of API/ABI changes
mm/kmemleak-test.c: use pr_fmt for logging
fs/dlm/debug_fs.c: replace seq_printf by seq_puts
fs/dlm/lockspace.c: convert simple_str to kstr
fs/dlm/config.c: convert simple_str to kstr
mm: mark remap_file_pages() syscall as deprecated
mm: memcontrol: remove unnecessary memcg argument from soft limit functions
mm: memcontrol: clean up memcg zoneinfo lookup
mm/memblock.c: call kmemleak directly from memblock_(alloc|free)
mm/mempool.c: update the kmemleak stack trace for mempool allocations
lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations
mm: introduce kmemleak_update_trace()
mm/kmemleak.c: use %u to print ->checksum
...
