There is already defined macro KEEP_SEGMENTS in
<asm/bootparam.h>, let's use it instead of hardcoded
constants.
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1424331298-7456-1-git-send-email-kuleshovmail@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
video.c is the only real user of the 'video_segment' variable,
so move it to video.c and make it static.
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Martin Mares <mj@ucw.cz>
Link: http://lkml.kernel.org/r/1422123092-28750-1-git-send-email-kuleshovmail@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
calls to avoid triple faults if an NMI/MCE is received.
* Revert Ard's change to the libstub get_memory_map() that went into
the v3.20 merge window because it causes boot regressions on Qemu and
Xen.
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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:
" - Leave a valid 64-bit IDT installed during runtime EFI mixed mode
calls to avoid triple faults if an NMI/MCE is received.
- Revert Ard's change to the libstub get_memory_map() that went into
the v3.20 merge window because it causes boot regressions on Qemu and
Xen. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Recently instrumentation of builtin functions calls was removed from GCC
5.0. To check the memory accessed by such functions, userspace asan
always uses interceptors for them.
So now we should do this as well. This patch declares
memset/memmove/memcpy as weak symbols. In mm/kasan/kasan.c we have our
own implementation of those functions which checks memory before accessing
it.
Default memset/memmove/memcpy now now always have aliases with '__'
prefix. For files that built without kasan instrumentation (e.g.
mm/slub.c) original mem* replaced (via #define) with prefixed variants,
cause we don't want to check memory accesses there.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds arch specific code for kernel address sanitizer.
16TB of virtual addressed used for shadow memory. It's located in range
[ffffec0000000000 - fffffc0000000000] between vmemmap and %esp fixup
stacks.
At early stage we map whole shadow region with zero page. Latter, after
pages mapped to direct mapping address range we unmap zero pages from
corresponding shadow (see kasan_map_shadow()) and allocate and map a real
shadow memory reusing vmemmap_populate() function.
Also replace __pa with __pa_nodebug before shadow initialized. __pa with
CONFIG_DEBUG_VIRTUAL=y make external function call (__phys_addr)
__phys_addr is instrumented, so __asan_load could be called before shadow
area initialized.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andy pointed out that if an NMI or MCE is received while we're in the
middle of an EFI mixed mode call a triple fault will occur. This can
happen, for example, when issuing an EFI mixed mode call while running
perf.
The reason for the triple fault is that we execute the mixed mode call
in 32-bit mode with paging disabled but with 64-bit kernel IDT handlers
installed throughout the call.
At Andy's suggestion, stop playing the games we currently do at runtime,
such as disabling paging and installing a 32-bit GDT for __KERNEL_CS. We
can simply switch to the __KERNEL32_CS descriptor before invoking
firmware services, and run in compatibility mode. This way, if an
NMI/MCE does occur the kernel IDT handler will execute correctly, since
it'll jump to __KERNEL_CS automatically.
However, this change is only possible post-ExitBootServices(). Before
then the firmware "owns" the machine and expects for its 32-bit IDT
handlers to be left intact to service interrupts, etc.
So, we now need to distinguish between early boot and runtime
invocations of EFI services. During early boot, we need to restore the
GDT that the firmware expects to be present. We can only jump to the
__KERNEL32_CS code segment for mixed mode calls after ExitBootServices()
has been invoked.
A liberal sprinkling of comments in the thunking code should make the
differences in early and late environments more apparent.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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
...
commit 7d453eee36 ("x86/efi: Wire up CONFIG_EFI_MIXED") introduced a
regression for the functionality to load kernels above 4G. The relevant
(incorrect) reasoning behind this change can be seen in the commit
message,
"The xloadflags field in the bzImage header is also updated to reflect
that the kernel supports both entry points by setting both of
XLF_EFI_HANDOVER_32 and XLF_EFI_HANDOVER_64 when CONFIG_EFI_MIXED=y.
XLF_CAN_BE_LOADED_ABOVE_4G is disabled so that the kernel text is
guaranteed to be addressable with 32-bits."
This is obviously bogus since 32-bit EFI loaders will never place the
kernel above the 4G mark. So this restriction is entirely unnecessary.
But things are worse than that - since we want to encourage people to
always compile with CONFIG_EFI_MIXED=y so that their kernels work out of
the box for both 32-bit and 64-bit firmware, commit 7d453eee36
effectively disables XLF_CAN_BE_LOADED_ABOVE_4G completely.
Remove the overzealous and superfluous restriction and restore the
XLF_CAN_BE_LOADED_ABOVE_4G functionality.
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1402140380-15377-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Pull x86 EFI updates from Peter Anvin:
"A collection of EFI changes. The perhaps most important one is to
fully save and restore the FPU state around each invocation of EFI
runtime, and to not choke on non-ASCII characters in the boot stub"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efivars: Add compatibility code for compat tasks
efivars: Refactor sanity checking code into separate function
efivars: Stop passing a struct argument to efivar_validate()
efivars: Check size of user object
efivars: Use local variables instead of a pointer dereference
x86/efi: Save and restore FPU context around efi_calls (i386)
x86/efi: Save and restore FPU context around efi_calls (x86_64)
x86/efi: Implement a __efi_call_virt macro
x86, fpu: Extend the use of static_cpu_has_safe
x86/efi: Delete most of the efi_call* macros
efi: x86: Handle arbitrary Unicode characters
efi: Add get_dram_base() helper function
efi: Add shared printk wrapper for consistent prefixing
efi: create memory map iteration helper
efi: efi-stub-helper cleanup
By changing code16gcc.h from a C header to an assembly header and use
the -Wa,... option to gcc to force it to be added to the assembly
input, we can avoid the problems with gcc reordering code bits on us.
If we have -m16, we still use it, of course.
Suggested-by: Kevin O'Connor <kevin@koconnor.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-xw8ibgdemucl9fz3i1bymu6w@git.kernel.org
Pull x86 boot changes from Ingo Molnar:
"Two small cleanups"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, boot: Remove misc.h inclusion from compressed/string.c
x86, boot: Do not include boot.h in string.c
Given the fact that we removed inclusion of boot.h from boot/string.c
does not look like we need misc.h inclusion in compressed/string.c. So
remove it.
misc.h was also pulling in string_32.h which in turn had macros for
memcmp and memcpy. So we don't need to #undef memcmp and memcpy anymore.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1398447972-27896-3-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
string.c does not require whole of boot.h. Just inclusion of linux/types.h
and ctypes.h seems to be sufficient.
Keep list of stuff being included in string.c to bare minimal so that
string.c can be included in other places easily.
For example, Currently boot/compressed/string.c includes boot/string.c
but looks like it does not want boot/boot.h. Hence there is a define
in boot/compressed/misc.h "define BOOT_BOOT_H" which prevents inclusion
of boot.h in compressed/string.c. And compressed/string.c is forced to
include misc.h just for that reason.
So by removing inclusion of boot.h, we can also get rid of inclusion of
misch.h in compressed/misc.c.
This also enables including of boot/string.c in purgatory/ code relatively
easily.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1398447972-27896-2-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
As requested by Linus add explicit __visible to the asmlinkage users.
This marks all functions visible to assembler.
Tree sweep for arch/x86/*
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1398984278-29319-3-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
arch/x86/crypto/sha1_avx2_x86_64_asm.S introduced _end as a local
symbol, which broke the build under certain circumstances. Although
the wisdom of _end as a local symbol can definitely be questioned, the
build should not break for that reason.
Thus, filter the output of nm to only get global symbols of
appropriate type.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Cc: Chandramouli Narayanan <mouli@linux.intel.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-uxm3j3w3odglcwhafwq5tjqu@git.kernel.org
We really only need one phys and one virt function call, and then only
one assembly function to make firmware calls.
Since we are not using the C type system anyway, we're not really losing
much by deleting the macros apart from no longer having a check that
we are passing the correct number of parameters. The lack of duplicated
code seems like a worthwhile trade-off.
Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Instead of truncating UTF-16 assuming all characters is ASCII,
properly convert it to UTF-8.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
[ Bug and style fixes. ]
Signed-off-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Pull x86 fixes from Peter Anvin:
"This is a collection of minor fixes for x86, plus the IRET information
leak fix (forbid the use of 16-bit segments in 64-bit mode)"
NOTE! We may have to relax the "forbid the use of 16-bit segments in
64-bit mode" part, since there may be people who still run and depend on
16-bit Windows binaries under Wine.
But I'm taking this in the current unconditional form for now to see who
(if anybody) screams bloody murder. Maybe nobody cares. And maybe
we'll have to update it with some kind of runtime enablement (like our
vm.mmap_min_addr tunable that people who run dosemu/qemu/wine already
need to tweak).
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels
efi: Pass correct file handle to efi_file_{read,close}
x86/efi: Correct EFI boot stub use of code32_start
x86/efi: Fix boot failure with EFI stub
x86/platform/hyperv: Handle VMBUS driver being a module
x86/apic: Reinstate error IRQ Pentium erratum 3AP workaround
x86, CMCI: Add proper detection of end of CMCI storms
firmware was reading random values from the stack because we were
passing a pointer to the wrong object type.
* Kernel corruption has been reported when booting with the EFI boot
stub which was tracked down to setting a bogus value for
bp->hdr.code32_start, resulting in corruption during relocation.
* Olivier Martin reported that the wrong file handles were being passed
to efi_file_(read|close), which works for x86 by luck due to the way
that the FAT driver is implemented, but doesn't work on ARM.
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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:
"* Fix EFI boot regression introduced during the merge window where the
firmware was reading random values from the stack because we were
passing a pointer to the wrong object type.
* Kernel corruption has been reported when booting with the EFI boot
stub which was tracked down to setting a bogus value for
bp->hdr.code32_start, resulting in corruption during relocation.
* Olivier Martin reported that the wrong file handles were being passed
to efi_file_(read|close), which works for x86 by luck due to the way
that the FAT driver is implemented, but doesn't work on ARM."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We're currently passing the file handle for the root file system to
efi_file_read() and efi_file_close(), instead of the file handle for the
file we wish to read/close.
While this has worked up until now, it seems that it has only been by
pure luck. Olivier explains,
"The issue is the UEFI Fat driver might return the same function for
'fh->read()' and 'h->read()'. While in our case it does not work with
a different implementation of EFI_SIMPLE_FILE_SYSTEM_PROTOCOL. In our
case, we return a different pointer when reading a directory and
reading a file."
Fixing this actually clears up the two functions because we can drop one
of the arguments, and instead only pass a file 'handle' argument.
Reported-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
code32_start should point at the start of the protected mode code, and
*not* at the beginning of the bzImage. This is much easier to do in
assembly so document that callers of make_boot_params() need to fill out
code32_start.
The fallout from this bug is that we would end up relocating the image
but copying the image at some offset, resulting in what appeared to be
memory corruption.
Reported-by: Thomas Bächler <thomas@archlinux.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
commit 54b52d8726 ("x86/efi: Build our own EFI services pointer
table") introduced a regression because the 64-bit file_size()
implementation passed a pointer to a 32-bit data object, instead of a
pointer to a 64-bit object.
Because the firmware treats the object as 64-bits regardless it was
reading random values from the stack for the upper 32-bits.
This resulted in people being unable to boot their machines, after
seeing the following error messages,
Failed to get file info size
Failed to alloc highmem for files
Reported-by: Dzmitry Sledneu <dzmitry.sledneu@gmail.com>
Reported-by: Koen Kooi <koen@dominion.thruhere.net>
Tested-by: Koen Kooi <koen@dominion.thruhere.net>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Pull x86 boot changes from Peter Anvin:
"This patchset is a set of cleanups aiming at librarize some of the
common code from the boot environments. We currently have three
different "little environments" (boot, boot/compressed, and
realmode/rm) in x86, and we are likely to soon get a fourth one
(kexec/purgatory, which will have to be integrated in the kernel to
support secure kexec). This is primarily a cleanup in the
anticipation of the latter.
While Vivek implemented this, he ran into some bugs, in particular the
memcmp implementation for when gcc punts from using the builtin would
have a misnamed symbol, causing compilation errors if we were ever
unlucky enough that gcc didn't want to inline the test"
* 'x86/boot' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, boot: Move memset() definition in compressed/string.c
x86, boot: Move memcmp() into string.h and string.c
x86, boot: Move optimized memcpy() 32/64 bit versions to compressed/string.c
x86, boot: Create a separate string.h file to provide standard string functions
x86, boot: Undef memcmp before providing a new definition
Pull x86 EFI changes from Ingo Molnar:
"The main changes:
- Add debug code to the dump EFI pagetable - Borislav Petkov
- Make 1:1 runtime mapping robust when booting on machines with lots
of memory - Borislav Petkov
- Move the EFI facilities bits out of 'x86_efi_facility' and into
efi.flags which is the standard architecture independent place to
keep EFI state, by Matt Fleming.
- Add 'EFI mixed mode' support: this allows 64-bit kernels to be
booted from 32-bit firmware. This needs a bootloader that supports
the 'EFI handover protocol'. By Matt Fleming"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
x86, efi: Abstract x86 efi_early calls
x86/efi: Restore 'attr' argument to query_variable_info()
x86/efi: Rip out phys_efi_get_time()
x86/efi: Preserve segment registers in mixed mode
x86/boot: Fix non-EFI build
x86, tools: Fix up compiler warnings
x86/efi: Re-disable interrupts after calling firmware services
x86/boot: Don't overwrite cr4 when enabling PAE
x86/efi: Wire up CONFIG_EFI_MIXED
x86/efi: Add mixed runtime services support
x86/efi: Firmware agnostic handover entry points
x86/efi: Split the boot stub into 32/64 code paths
x86/efi: Add early thunk code to go from 64-bit to 32-bit
x86/efi: Build our own EFI services pointer table
efi: Add separate 32-bit/64-bit definitions
x86/efi: Delete dead code when checking for non-native
x86/mm/pageattr: Always dump the right page table in an oops
x86, tools: Consolidate #ifdef code
x86/boot: Cleanup header.S by removing some #ifdefs
efi: Use NULL instead of 0 for pointer
...
Pull x86 cpu handling changes from Ingo Molnar:
"Bigger changes:
- Intel CPU hardware-enablement: new vector instructions support
(AVX-512), by Fenghua Yu.
- Support the clflushopt instruction and use it in appropriate
places. clflushopt is similar to clflush but with more relaxed
ordering, by Ross Zwisler.
- MSR accessor cleanups, by Borislav Petkov.
- 'forcepae' boot flag for those who have way too much time to spend
on way too old Pentium-M systems and want to live way too
dangerously, by Chris Bainbridge"
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M
Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC
x86, intel: Make MSR_IA32_MISC_ENABLE bit constants systematic
x86, Intel: Convert to the new bit access MSR accessors
x86, AMD: Convert to the new bit access MSR accessors
x86: Add another set of MSR accessor functions
x86: Use clflushopt in drm_clflush_virt_range
x86: Use clflushopt in drm_clflush_page
x86: Use clflushopt in clflush_cache_range
x86: Add support for the clflushopt instruction
x86, AVX-512: Enable AVX-512 States Context Switch
x86, AVX-512: AVX-512 Feature Detection
The ARM EFI boot stub doesn't need to care about the efi_early
infrastructure that x86 requires in order to do mixed mode thunking. So
wrap everything up in an efi_call_early() macro.
This allows x86 to do the necessary indirection jumps to call whatever
firmware interface is necessary (native or mixed mode), but also allows
the ARM folks to mask the fact that they don't support relocation in the
boot stub and need to pass 'sys_table_arg' to every function.
[ hpa: there are no object code changes from this patch ]
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/20140326091011.GB2958@console-pimps.org
Cc: Roy Franz <roy.franz@linaro.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Many Pentium M systems disable PAE but may have a functionally usable PAE
implementation. This adds the "forcepae" parameter which bypasses the boot
check for PAE, and sets the CPU as being PAE capable. Using this parameter
will taint the kernel with TAINT_CPU_OUT_OF_SPEC.
Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Currently compressed/misc.c needs to link against memset(). I think one of
the reasons of this need is inclusion of various header files which define
static inline functions and use memset() inside these. For example,
include/linux/bitmap.h
I think trying to include "../string.h" and using builtin version of memset
does not work because by the time "#define memset" shows up, it is too
late. Some other header file has already used memset() and expects to
find a definition during link phase.
Currently we have a C definitoin of memset() in misc.c. Move it to
compressed/string.c so that others can use it if need be.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-6-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Try to treat memcmp() in same way as memcpy() and memset(). Provide a
declaration in boot/string.h and by default user gets a memcmp() which
maps to builtin function.
Move optimized definition of memcmp() in boot/string.c. Now a user can
do #undef memcmp and link against string.c to use optimzied memcmp().
It also simplifies boot/compressed/string.c where we had to redefine
memcmp(). That extra definition is gone now.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-5-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Move optimized versions of memcpy to compressed/string.c This will allow
any other code to use these functions too if need be in future. Again
trying to put definition in a common place instead of hiding it in misc.c
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-4-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Create a separate arch/x86/boot/string.h file to provide declaration of
some of the common string functions.
By default memcpy, memset and memcmp functions will default to gcc
builtin functions. If code wants to use an optimized version of any
of these functions, they need to #undef the respective macro and link
against a local file providing definition of undefed function.
For example, arch/x86/boot/* code links against copy.S to get memcpy()
and memcmp() definitions. arch/86/boot/compressed/* links against
compressed/string.c.
There are quite a few places in arch/x86/ where these functions are
used. Idea is to try to consilidate their declaration and possibly
definitions so that it can be reused.
I am planning to reuse boot/string.h in arch/x86/purgatory/ and use
gcc builtin functions for memcpy, memset and memcmp.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-3-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
With CONFIG_X86_32=y, string_32.h gets pulled in compressed/string.c by
"misch.h". string_32.h defines a macro to map memcmp to __builtin_memcmp().
And that macro in turn changes the name of memcmp() defined here and
converts it to __builtin_memcmp().
I thought that's not the intention though. We probably want to provide
our own optimized definition of memcmp(). If yes, then undef the memcmp
before we define a new memcmp.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-2-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The kbuild test robot reported the following errors, introduced with
commit 54b52d8726 ("x86/efi: Build our own EFI services pointer
table"),
arch/x86/boot/compressed/head_32.o: In function `efi32_config':
>> (.data+0x58): undefined reference to `efi_call_phys'
arch/x86/boot/compressed/head_64.o: In function `efi64_config':
>> (.data+0x90): undefined reference to `efi_call6'
Wrap the efi*_config structures in #ifdef CONFIG_EFI_STUB so that we
don't make references to EFI functions if they're not compiled in.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
The kbuild test robot reported the following errors that were introduced
with commit 993c30a04e ("x86, tools: Consolidate #ifdef code"),
arch/x86/boot/tools/build.c: In function 'update_pecoff_setup_and_reloc':
>> arch/x86/boot/tools/build.c:252:1: error: parameter name omitted
static inline void update_pecoff_setup_and_reloc(unsigned int) {}
^
arch/x86/boot/tools/build.c: In function 'update_pecoff_text':
>> arch/x86/boot/tools/build.c:253:1: error: parameter name omitted
static inline void update_pecoff_text(unsigned int, unsigned int) {}
^
>> arch/x86/boot/tools/build.c:253:1: error: parameter name omitted
arch/x86/boot/tools/build.c: In function 'main':
>> arch/x86/boot/tools/build.c:372:2: warning: implicit declaration of function 'efi_stub_entry_update' [-Wimplicit-function-declaration]
efi_stub_entry_update();
^
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Some EFI firmware makes use of the FPU during boottime services and
clearing X86_CR4_OSFXSR by overwriting %cr4 causes the firmware to
crash.
Add the PAE bit explicitly instead of trashing the existing contents,
leaving the rest of the bits as the firmware set them.
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Add the Kconfig option and bump the kernel header version so that boot
loaders can check whether the handover code is available if they want.
The xloadflags field in the bzImage header is also updated to reflect
that the kernel supports both entry points by setting both of
XLF_EFI_HANDOVER_32 and XLF_EFI_HANDOVER_64 when CONFIG_EFI_MIXED=y.
XLF_CAN_BE_LOADED_ABOVE_4G is disabled so that the kernel text is
guaranteed to be addressable with 32-bits.
Note that no boot loaders should be using the bits set in xloadflags to
decide which entry point to jump to. The entire scheme is based on the
concept that 32-bit bootloaders always jump to ->handover_offset and
64-bit loaders always jump to ->handover_offset + 512. We set both bits
merely to inform the boot loader that it's safe to use the native
handover offset even if the machine type in the PE/COFF header claims
otherwise.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
The EFI handover code only works if the "bitness" of the firmware and
the kernel match, i.e. 64-bit firmware and 64-bit kernel - it is not
possible to mix the two. This goes against the tradition that a 32-bit
kernel can be loaded on a 64-bit BIOS platform without having to do
anything special in the boot loader. Linux distributions, for one thing,
regularly run only 32-bit kernels on their live media.
Despite having only one 'handover_offset' field in the kernel header,
EFI boot loaders use two separate entry points to enter the kernel based
on the architecture the boot loader was compiled for,
(1) 32-bit loader: handover_offset
(2) 64-bit loader: handover_offset + 512
Since we already have two entry points, we can leverage them to infer
the bitness of the firmware we're running on, without requiring any boot
loader modifications, by making (1) and (2) valid entry points for both
CONFIG_X86_32 and CONFIG_X86_64 kernels.
To be clear, a 32-bit boot loader will always use (1) and a 64-bit boot
loader will always use (2). It's just that, if a single kernel image
supports (1) and (2) that image can be used with both 32-bit and 64-bit
boot loaders, and hence both 32-bit and 64-bit EFI.
(1) and (2) must be 512 bytes apart at all times, but that is already
part of the boot ABI and we could never change that delta without
breaking existing boot loaders anyhow.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Implement the transition code to go from IA32e mode to protected mode in
the EFI boot stub. This is required to use 32-bit EFI services from a
64-bit kernel.
Since EFI boot stub is executed in an identity-mapped region, there's
not much we need to do before invoking the 32-bit EFI boot services.
However, we do reload the firmware's global descriptor table
(efi32_boot_gdt) in case things like timer events are still running in
the firmware.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
It's not possible to dereference the EFI System table directly when
booting a 64-bit kernel on a 32-bit EFI firmware because the size of
pointers don't match.
In preparation for supporting the above use case, build a list of
function pointers on boot so that callers don't have to worry about
converting pointer sizes through multiple levels of indirection.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
The traditional approach of using machine-specific types such as
'unsigned long' does not allow the kernel to interact with firmware
running in a different CPU mode, e.g. 64-bit kernel with 32-bit EFI.
Add distinct EFI structure definitions for both 32-bit and 64-bit so
that we can use them in the 32-bit and 64-bit code paths.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Instead of littering main() with #ifdef CONFIG_EFI_STUB, move the logic
into separate functions that do nothing if the config option isn't set.
This makes main() much easier to read.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
handover_offset is now filled out by build.c. Don't set a default value
as it will be overwritten anyway.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Commit dd78b97367 ("x86, boot: Move CPU
flags out of cpucheck") introduced ambiguous inline asm in the
has_eflag() function. In 16-bit mode want the instruction to be
'pushfl', but we just say 'pushf' and hope the compiler does what we
wanted.
When building with 'clang -m16', it won't, because clang doesn't use
the horrid '.code16gcc' hack that even 'gcc -m16' uses internally.
Say what we mean and don't make the compiler make assumptions.
[ hpa: ideally we would be able to use the gcc %zN construct here, but
that is broken for 64-bit integers in gcc < 4.5.
The code with plain "pushf/popf" is fine for 32- or 64-bit mode, but
not for 16-bit mode; in 16-bit mode those are 16-bit instructions in
.code16 mode, and 32-bit instructions in .code16gcc mode. ]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1391079628.26079.82.camel@shinybook.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
It looks like GCC will always emit an object that is marked with an
explicit section, although the documentation doesn't say that and we
possibly shouldn't be relying on it.
Clang does *not* do so, so add __attribute__((used)) to make sure.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1389180083-23249-2-git-send-email-David.Woodhouse@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
