If we get a vmalloc fault while current->active_mm->pgd doesn't
match CR3, we'll crash without this change. I've seen this failure
mode on heavily instrumented kernels with virtually mapped stacks.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4650d7674185f165ed8fdf9ac4c5c35c5c179ba8.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If we overflow the stack into a guard page, we'll recursively fault
when trying to dump the contents of the guard page. Use
probe_kernel_address() so we can recover if this happens.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e626d47a55d7b04dcb1b4d33faa95e8505b217c8.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If we overflow the stack, print_context_stack() will abort. Detect
this case and rewind back into the valid part of the stack so that
we can trace it.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/ee1690eb2715ccc5dc187fde94effa4ca0ccbbcd.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel_unmap_pages_in_pgd() is dangerous: if a PGD entry in
init_mm.pgd were to be cleared, callers would need to ensure that
the pgd entry hadn't been propagated to any other pgd.
Its only caller was efi_cleanup_page_tables(), and that, in turn,
was unused, so just delete both functions. This leaves a couple of
other helpers unused, so delete them, too.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/77ff20fdde3b75cd393be5559ad8218870520248.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This avoids pointless races in which another CPU or task might see a
partially populated global PGD entry. These races should normally
be harmless, but, if another CPU propagates the entry via
vmalloc_fault() and then populate_pgd() fails (due to memory allocation
failure, for example), this prevents a use-after-free of the PGD
entry.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/bf99df27eac6835f687005364bd1fbd89130946c.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So when memory hotplug removes a piece of physical memory from pagetable
mappings, it also frees the underlying PGD entry.
This complicates PGD management, so don't do this. We can keep the
PGD mapped and the PUD table all clear - it's only a single 4K page
per 512 GB of memory hotplugged.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <Waiman.Long@hp.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/064ff6c7275734537f969e876f6cd0baa954d2cc.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The page table manipulation code seems to have grown a couple of
sites that are looking for empty PTEs. Just in case one of these
entries got a stray bit set, use pte_none() instead of checking
for a zero pte_val().
The use pte_same() makes me a bit nervous. If we were doing a
pte_same() check against two cleared entries and one of them had
a stray bit set, it might fail the pte_same() check. But, I
don't think we ever _do_ pte_same() for cleared entries. It is
almost entirely used for checking for races in fault-in paths.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dave.hansen@intel.com
Cc: linux-mm@kvack.org
Cc: mhocko@suse.com
Link: http://lkml.kernel.org/r/20160708001915.813703D9@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Intel(R) Xeon Phi(TM) Processor x200 Family (codename: Knights
Landing) has an erratum where a processor thread setting the Accessed
or Dirty bits may not do so atomically against its checks for the
Present bit. This may cause a thread (which is about to page fault)
to set A and/or D, even though the Present bit had already been
atomically cleared.
These bits are truly "stray". In the case of the Dirty bit, the
thread associated with the stray set was *not* allowed to write to
the page. This means that we do not have to launder the bit(s); we
can simply ignore them.
If the PTE is used for storing a swap index or a NUMA migration index,
the A bit could be misinterpreted as part of the swap type. The stray
bits being set cause a software-cleared PTE to be interpreted as a
swap entry. In some cases (like when the swap index ends up being
for a non-existent swapfile), the kernel detects the stray value
and WARN()s about it, but there is no guarantee that the kernel can
always detect it.
When we have 64-bit PTEs (64-bit mode or 32-bit PAE), we were able
to move the swap PTE format around to avoid these troublesome bits.
But, 32-bit non-PAE is tight on bits. So, disallow it from running
on this hardware. I can't imagine anyone wanting to run 32-bit
non-highmem kernels on this hardware, but disallowing them from
running entirely is surely the safe thing to do.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dave.hansen@intel.com
Cc: linux-mm@kvack.org
Cc: mhocko@suse.com
Link: http://lkml.kernel.org/r/20160708001914.D0B50110@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The erratum we are fixing here can lead to stray setting of the
A and D bits. That means that a pte that we cleared might
suddenly have A/D set. So, stop considering those bits when
determining if a pte is pte_none(). The same goes for the
other pmd_none() and pud_none(). pgd_none() can be skipped
because it is not affected; we do not use PGD entries for
anything other than pagetables on affected configurations.
This adds a tiny amount of overhead to all pte_none() checks.
I doubt we'll be able to measure it anywhere.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dave.hansen@intel.com
Cc: linux-mm@kvack.org
Cc: mhocko@suse.com
Link: http://lkml.kernel.org/r/20160708001912.5216F89C@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This erratum can result in Accessed/Dirty getting set by the hardware
when we do not expect them to be (on !Present PTEs).
Instead of trying to fix them up after this happens, we just
allow the bits to get set and try to ignore them. We do this by
shifting the layout of the bits we use for swap offset/type in
our 64-bit PTEs.
It looks like this:
bitnrs: | ... | 11| 10| 9|8|7|6|5| 4| 3|2|1|0|
names: | ... |SW3|SW2|SW1|G|L|D|A|CD|WT|U|W|P|
before: | OFFSET (9-63) |0|X|X| TYPE(1-5) |0|
after: | OFFSET (14-63) | TYPE (9-13) |0|X|X|X| X| X|X|X|0|
Note that D was already a don't care (X) even before. We just
move TYPE up and turn its old spot (which could be hit by the
A bit) into all don't cares.
We take 5 bits away from the offset, but that still leaves us
with 50 bits which lets us index into a 62-bit swapfile (4 EiB).
I think that's probably fine for the moment. We could
theoretically reclaim 5 of the bits (1, 2, 3, 4, 7) but it
doesn't gain us anything.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dave.hansen@intel.com
Cc: linux-mm@kvack.org
Cc: mhocko@suse.com
Link: http://lkml.kernel.org/r/20160708001911.9A3FD2B6@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This matches what is already done for prepare_exit_to_usermode(),
and saves about 60 clock cycles (4% speedup) with the benchmark
in the previous commit message.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1466434712-31440-3-git-send-email-pbonzini@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thanks to all the work that was done by Andy Lutomirski and others,
enter_from_user_mode() and prepare_exit_to_usermode() are now called only with
interrupts disabled. Let's provide them a version of user_enter()/user_exit()
that skips saving and restoring the interrupt flag.
On an AMD-based machine I tested this patch on, with force-enabled
context tracking, the speed-up in system calls was 90 clock cycles or 6%,
measured with the following simple benchmark:
#include <sys/signal.h>
#include <time.h>
#include <unistd.h>
#include <stdio.h>
unsigned long rdtsc()
{
unsigned long result;
asm volatile("rdtsc; shl $32, %%rdx; mov %%eax, %%eax\n"
"or %%rdx, %%rax" : "=a" (result) : : "rdx");
return result;
}
int main()
{
unsigned long tsc1, tsc2;
int pid = getpid();
int i;
tsc1 = rdtsc();
for (i = 0; i < 100000000; i++)
kill(pid, SIGWINCH);
tsc2 = rdtsc();
printf("%ld\n", tsc2 - tsc1);
}
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1466434712-31440-2-git-send-email-pbonzini@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Enforce USER_DS on exception entry from EL1
- Apply workaround for Cavium errata #27456 on Thunderx-81xx parts
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABCgAGBQJXf5pkAAoJELescNyEwWM0CrwH/RTFmTDzlvwJbcmVKLeabfSb
8AUphL7+D8gRLBRy1l+pdjqHli4EuxA34peaIHs91ziPl85wI+l37juTZ08MqYUM
W3lLbKPmJGa39WKYq5rtKqaohCGHRA0SwLSq78kbRFb3GgWUvNbrUaC5oBoEOBkc
x2vEpsVVhAWezly1CaX0zf8yfBuGp5O8rkw2yFqPuD7MKh3D0DLK4F8UCmZ9OqQM
nI10nq9GBdbus8yA/2kIHSvtkGC9l0Cyiu8iJ/Gf4HQnSqVopPAzvP0FdNs5cj9o
5m/BOJUED/pEdps7+PZMlJHYrHpB+VTqrZ/HdFFI4M5EsIltw3OSKp/lA6cA/Xc=
=iKFx
-----END PGP SIGNATURE-----
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"A couple of late fixes here, but one that we've been sitting on for a
few weeks while the details were worked out. Specifically, we now
enforce USER_DS on taking exceptions whilst in the kernel, which
avoids leaking kernel data to userspace through things like perf. The
other patch is an update to a workaround for a hardware erratum on
some Cavium SoCs.
Summary:
- Enforce USER_DS on exception entry from EL1
- Apply workaround for Cavium errata #27456 on Thunderx-81xx parts"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Enable workaround for Cavium erratum 27456 on thunderx-81xx
arm64: kernel: Save and restore UAO and addr_limit on exception entry
Pull x86 fixes from Ingo Molnar:
"Three fixes:
- A boot crash fix with certain configs
- a MAINTAINERS entry update
- Documentation typo fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/Documentation: Fix various typos in Documentation/x86/ files
x86/amd_nb: Fix boot crash on non-AMD systems
MAINTAINERS: Update the Calgary IOMMU entry
Pull perf fixes from Ingo Molnar:
"Various fixes:
- 32-bit callgraph bug fix
- suboptimal event group scheduling bug fix
- event constraint fixes for Broadwell/Skylake
- RAPL module name collision fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix pmu::filter_match for SW-led groups
x86/perf/intel/rapl: Fix module name collision with powercap intel-rapl
perf/x86: Fix 32-bit perf user callgraph collection
perf/x86/intel: Update event constraints when HT is off
No need to have it appear in objdump output.
No functionality change.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160708141016.GH3808@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add possibility for 32-bit user-space applications to move
the vDSO mapping.
Previously, when a user-space app called mremap() for the vDSO
address, in the syscall return path it would land on the previous
address of the vDSOpage, resulting in segmentation violation.
Now it lands fine and returns to userspace with a remapped vDSO.
This will also fix the context.vdso pointer for 64-bit, which does
not affect the user of vDSO after mremap() currently, but this
may change in the future.
As suggested by Andy, return -EINVAL for mremap() that would
split the vDSO image: that operation cannot possibly result in
a working system so reject it.
Renamed and moved the text_mapping structure declaration inside
map_vdso(), as it used only there and now it complements the
vvar_mapping variable.
There is still a problem for remapping the vDSO in glibc
applications: the linker relocates addresses for syscalls
on the vDSO page, so you need to relink with the new
addresses.
Without that the next syscall through glibc may fail:
Program received signal SIGSEGV, Segmentation fault.
#0 0xf7fd9b80 in __kernel_vsyscall ()
#1 0xf7ec8238 in _exit () from /usr/lib32/libc.so.6
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: 0x7f454c46@gmail.com
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20160628113539.13606-2-dsafonov@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently it's possible for broken (or malicious) userspace to flood a
kernel log indefinitely with messages a-la
Program dmidecode tried to access /dev/mem between f0000->100000
because range_is_allowed() is case of CONFIG_STRICT_DEVMEM being turned on
dumps this information each and every time devmem_is_allowed() fails.
Reportedly userspace that is able to trigger contignuous flow of these
messages exists.
It would be possible to rate limit this message, but that'd have a
questionable value; the administrator wouldn't get information about all
the failing accessess, so then the information would be both superfluous
and incomplete at the same time :)
Returning EPERM (which is what is actually happening) is enough indication
for userspace what has happened; no need to log this particular error as
some sort of special condition.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1607081137020.24757@cbobk.fhfr.pm
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Fix a lock ordering issue in ACPICA introduced by a recent commit
that attempted to fix a deadlock in the dynamic table loading code
which in turn appeared after changes related to the handling of
module-level AML also made in this cycle (Lv Zheng).
- Fix a recent regression in the ACPI IRQ management code that may
cause PCI drivers to be unable to register an IRQ if that IRQ
happens to be shared with a device on the ISA bus, like the
parallel port, by reverting one commit entirely and restoring the
previous behavior in two other places (Sinan Kaya).
- Fix a recent regression in the ACPI AML debugger introduced by
the commit that removed incorrect usage of IS_ERR_VALUE() from
multiple places (Lv Zheng).
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=vKn9
-----END PGP SIGNATURE-----
Merge tag 'acpi-4.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fixes from Rafael Wysocki:
"All of these fix recent regressions in ACPICA, in the ACPI PCI IRQ
management code and in the ACPI AML debugger.
Specifics:
- Fix a lock ordering issue in ACPICA introduced by a recent commit
that attempted to fix a deadlock in the dynamic table loading code
which in turn appeared after changes related to the handling of
module-level AML also made in this cycle (Lv Zheng).
- Fix a recent regression in the ACPI IRQ management code that may
cause PCI drivers to be unable to register an IRQ if that IRQ
happens to be shared with a device on the ISA bus, like the
parallel port, by reverting one commit entirely and restoring the
previous behavior in two other places (Sinan Kaya).
- Fix a recent regression in the ACPI AML debugger introduced by the
commit that removed incorrect usage of IS_ERR_VALUE() from multiple
places (Lv Zheng)"
* tag 'acpi-4.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / debugger: Fix regression introduced by IS_ERR_VALUE() removal
ACPICA: Namespace: Fix namespace/interpreter lock ordering
ACPI,PCI,IRQ: separate ISA penalty calculation
Revert "ACPI, PCI, IRQ: remove redundant code in acpi_irq_penalty_init()"
ACPI,PCI,IRQ: factor in PCI possible
Cavium erratum 27456 commit 104a0c02e8
("arm64: Add workaround for Cavium erratum 27456")
is applicable for thunderx-81xx pass1.0 SoC as well.
Adding code to enable to 81xx.
Signed-off-by: Ganapatrao Kulkarni <gkulkarni@cavium.com>
Reviewed-by: Andrew Pinski <apinski@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
If we take an exception while at EL1, the exception handler inherits
the original context's addr_limit and PSTATE.UAO values. To be consistent
always reset addr_limit and PSTATE.UAO on (re-)entry to EL1. This
prevents accidental re-use of the original context's addr_limit.
Based on a similar patch for arm from Russell King.
Cc: <stable@vger.kernel.org> # 4.6-
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Since commit 4b6e2571bf the rapl perf module calls itself intel-rapl. That
name was already in use by the rapl powercap driver, which now fails to load
if the perf module is loaded. Fix the problem by renaming the perf module to
intel-rapl-perf, so that both modules can coexist.
Fixes: 4b6e2571bf ("x86/perf/intel/rapl: Make the Intel RAPL PMU driver modular")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1466694409-3620-1-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch updates the event constraints for non-PEBS mode for
Intel Broadwell and Skylake processors. When HT is off, each
CPU gets 8 generic counters. However, not all events can be
programmed on any of the 8 counters. This patch adds the
constraints for the MEM_* events which can only be measured on the
bottom 4 counters. The constraints are also valid when HT is off
because, then, there are only 4 generic counters and they are the
bottom counters.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1467411742-13245-1-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull MIPS fix from Ralf Baechle:
"Only a single fix for 4.7 pending at this point. It fixes an issue
that may lead to corruption of the cache mode bits in the page table"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: Fix possible corruption of cache mode by mprotect.
- tm: Always reclaim in start_thread() for exec() class syscalls from Cyril Bur
- tm: Avoid SLB faults in treclaim/trecheckpoint when RI=0 from Michael Neuling
- eeh: Fix wrong argument passed to eeh_rmv_device() from Gavin Shan
- Initialise pci_io_base as early as possible from Darren Stevens
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=oEAY
-----END PGP SIGNATURE-----
Merge tag 'powerpc-4.7-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- tm: Always reclaim in start_thread() for exec() class syscalls from
Cyril Bur
- tm: Avoid SLB faults in treclaim/trecheckpoint when RI=0 from Michael
Neuling
- eeh: Fix wrong argument passed to eeh_rmv_device() from Gavin Shan
- Initialise pci_io_base as early as possible from Darren Stevens
* tag 'powerpc-4.7-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: Initialise pci_io_base as early as possible
powerpc/tm: Avoid SLB faults in treclaim/trecheckpoint when RI=0
powerpc/eeh: Fix wrong argument passed to eeh_rmv_device()
powerpc/tm: Always reclaim in start_thread() for exec() class syscalls
The following testcase may result in a page table entries with a invalid
CCA field being generated:
static void *bindstack;
static int sysrqfd;
static void protect_low(int protect)
{
mprotect(bindstack, BINDSTACK_SIZE, protect);
}
static void sigbus_handler(int signal, siginfo_t * info, void *context)
{
void *addr = info->si_addr;
write(sysrqfd, "x", 1);
printf("sigbus, fault address %p (should not happen, but might)\n",
addr);
abort();
}
static void run_bind_test(void)
{
unsigned int *p = bindstack;
p[0] = 0xf001f001;
write(sysrqfd, "x", 1);
/* Set trap on access to p[0] */
protect_low(PROT_NONE);
write(sysrqfd, "x", 1);
/* Clear trap on access to p[0] */
protect_low(PROT_READ | PROT_WRITE | PROT_EXEC);
write(sysrqfd, "x", 1);
/* Check the contents of p[0] */
if (p[0] != 0xf001f001) {
write(sysrqfd, "x", 1);
/* Reached, but shouldn't be */
printf("badness, shouldn't happen but does\n");
abort();
}
}
int main(void)
{
struct sigaction sa;
sysrqfd = open("/proc/sysrq-trigger", O_WRONLY);
if (sigprocmask(SIG_BLOCK, NULL, &sa.sa_mask)) {
perror("sigprocmask");
return 0;
}
sa.sa_sigaction = sigbus_handler;
sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART;
if (sigaction(SIGBUS, &sa, NULL)) {
perror("sigaction");
return 0;
}
bindstack = mmap(NULL,
BINDSTACK_SIZE,
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (bindstack == MAP_FAILED) {
perror("mmap bindstack");
return 0;
}
printf("bindstack: %p\n", bindstack);
run_bind_test();
printf("done\n");
return 0;
}
There are multiple ingredients for this:
1) PAGE_NONE is defined to _CACHE_CACHABLE_NONCOHERENT, which is CCA 3
on all platforms except SB1 where it's CCA 5.
2) _page_cachable_default must have bits set which are not set
_CACHE_CACHABLE_NONCOHERENT.
3) Either the defective version of pte_modify for XPA or the standard
version must be in used. However pte_modify for the 36 bit address
space support is no affected.
In that case additional bits in the final CCA mode may generate an invalid
value for the CCA field. On the R10000 system where this was tracked
down for example a CCA 7 has been observed, which is Uncached Accelerated.
Fixed by:
1) Using the proper CCA mode for PAGE_NONE just like for all the other
PAGE_* pte/pmd bits.
2) Fix the two affected variants of pte_modify.
Further code inspection also shows the same issue to exist in pmd_modify
which would affect huge page systems.
Issue in pte_modify tracked down by Alastair Bridgewater, PAGE_NONE
and pmd_modify issue found by me.
The history of this goes back beyond Linus' git history. Chris Dearman's
commit 351336929c ("[MIPS] Allow setting of
the cache attribute at run time.") missed the opportunity to fix this
but it was originally introduced in lmo commit
d523832cf12007b3242e50bb77d0c9e63e0b6518 ("Missing from last commit.")
and 32cc38229ac7538f2346918a09e75413e8861f87 ("New configuration option
CONFIG_MIPS_UNCACHED.")
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported-by: Alastair Bridgewater <alastair.bridgewater@gmail.com>
Trying to make the ISA and PCI init functionality common turned out
to be a bad idea, because the ISA path depends on external
functionality.
Restore the previous behavior and limit the refactoring to PCI
interrupts only.
Fixes: 1fcb6a813c "ACPI,PCI,IRQ: remove redundant code in acpi_irq_penalty_init()"
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Tested-by: Wim Osterholt <wim@djo.tudelft.nl>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix boot crash that triggers if this driver is built into a kernel and
run on non-AMD systems.
AMD northbridges users call amd_cache_northbridges() and it returns
a negative value to signal that we weren't able to cache/detect any
northbridges on the system.
At least, it should do so as all its callers expect it to do so. But it
does return a negative value only when kmalloc() fails.
Fix it to return -ENODEV if there are no NBs cached as otherwise, amd_nb
users like amd64_edac, for example, which relies on it to know whether
it should load or not, gets loaded on systems like Intel Xeons where it
shouldn't.
Reported-and-tested-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1466097230-5333-2-git-send-email-bp@alien8.de
Link: https://lkml.kernel.org/r/5761BEB0.9000807@cybernetics.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Logan Gunthorpe reports that hibernation stopped working reliably for
him after commit ab76f7b4ab (x86/mm: Set NX on gap between __ex_table
and rodata).
That turns out to be a consequence of a long-standing issue with the
64-bit image restoration code on x86, which is that the temporary
page tables set up by it to avoid page tables corruption when the
last bits of the image kernel's memory contents are copied into
their original page frames re-use the boot kernel's text mapping,
but that mapping may very well get corrupted just like any other
part of the page tables. Of course, if that happens, the final
jump to the image kernel's entry point will go to nowhere.
The exact reason why commit ab76f7b4ab matters here is that it
sometimes causes a PMD of a large page to be split into PTEs
that are allocated dynamically and get corrupted during image
restoration as described above.
To fix that issue note that the code copying the last bits of the
image kernel's memory contents to the page frames occupied by them
previoulsy doesn't use the kernel text mapping, because it runs from
a special page covered by the identity mapping set up for that code
from scratch. Hence, the kernel text mapping is only needed before
that code starts to run and then it will only be used just for the
final jump to the image kernel's entry point.
Accordingly, the temporary page tables set up in swsusp_arch_resume()
on x86-64 need to contain the kernel text mapping too. That mapping
is only going to be used for the final jump to the image kernel, so
it only needs to cover the image kernel's entry point, because the
first thing the image kernel does after getting control back is to
switch over to its own original page tables. Moreover, the virtual
address of the image kernel's entry point in that mapping has to be
the same as the one mapped by the image kernel's page tables.
With that in mind, modify the x86-64's arch_hibernation_header_save()
and arch_hibernation_header_restore() routines to pass the physical
address of the image kernel's entry point (in addition to its virtual
address) to the boot kernel (a small piece of assembly code involved
in passing the entry point's virtual address to the image kernel is
not necessary any more after that, so drop it). Update RESTORE_MAGIC
too to reflect the image header format change.
Next, in set_up_temporary_mappings(), use the physical and virtual
addresses of the image kernel's entry point passed in the image
header to set up a minimum kernel text mapping (using memory pages
that won't be overwritten by the image kernel's memory contents) that
will map those addresses to each other as appropriate.
This makes the concern about the possible corruption of the original
boot kernel text mapping go away and if the the minimum kernel text
mapping used for the final jump marks the image kernel's entry point
memory as executable, the jump to it is guaraneed to succeed.
Fixes: ab76f7b4ab (x86/mm: Set NX on gap between __ex_table and rodata)
Link: http://marc.info/?l=linux-pm&m=146372852823760&w=2
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJXdTiMAAoJEL/70l94x66D070H/ifn+e3nWddEeBTCjyELQiu+
a0h81Vk+QYMbtzZ76lr7gn31LTWbiI/yUBC/kAJCaiN3X44PTqJUhSLPiP/93/2S
A+/LZPtyjT5Qq8t0M4zByveOcT3AXI2akln/7b1rdHN4gyPqFJfGk2y0O5qttfi/
fhHqceKsUWfi2jMw3n6JtbshykhBbUMacq2suQLsX3vDPaC3dn64GAyDVYKfHaCl
7YzUmRJeXceQ4IQBXVoSnj/Bf5JDdUNglJl7zOeZlIcZnxhmCx5Uh3qRm3kdh4K0
yi76iwTAIbDI6DuFB09Sbr8lCxZCTTc2HsII1n8FrqlBZB6rDQlvfuRUR5DgbK0=
=b7zY
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"ARM and x86 fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: nVMX: VMX instructions: fix segment checks when L1 is in long mode.
KVM: LAPIC: cap __delay at lapic_timer_advance_ns
KVM: x86: move nsec_to_cycles from x86.c to x86.h
pvclock: Get rid of __pvclock_read_cycles in function pvclock_read_flags
pvclock: Cleanup to remove function pvclock_get_nsec_offset
pvclock: Add CPU barriers to get correct version value
KVM: arm/arm64: Stop leaking vcpu pid references
arm64: KVM: fix build with CONFIG_ARM_PMU disabled
- Reinstate dwarf unwinder/loadable-modules with new gnu tools
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=ABub
-----END PGP SIGNATURE-----
Merge tag 'arc-4.7-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fix from Vineet Gupta:
"Reinstate dwarf unwinder/loadable-modules with new gnu tools"
* tag 'arc-4.7-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
arc: unwind: warn only once if DW2_UNWIND is disabled
ARC: unwind: ensure that .debug_frame is generated (vs. .eh_frame)
Fixes a build issue without CONFIG_ARM_PMU and plugs pid leak on arm/arm64.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXdSB4AAoJEEtpOizt6ddyg10H/1lQnxqF8K+NOIahMMvDs26N
efujHsGlwHjCQTjThb+BC4qfA2tvcbZ+0UIV0mgvk750llVlrAz83aw83Wvgll9L
hDIwE55yePR9zFeOtTnwLOSIhYyeozSC58RB1OR8oQ1IzHIuokFx/3Iylbk7UjY0
y5LAxdNRWUK7IsFrnC2u8kfYaT+6xxV40KFE23NlCy8drHesrbEPOzDwRpX51u2z
o/68icxpU6TakmTZQwM5RvpgoTn1uEGneSgLSYbVlnHtkA1tr97+fOTFlzmFJyQj
oM7Mk7d9hRSr77dkXKwsDIGVcd0kRvzax2taGHmrrcPgDpkl0PHAfkseWKbb3LI=
=yPs9
-----END PGP SIGNATURE-----
Merge tag 'kvm-arm-for-v4.7-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master
KVM/ARM Fixes for v4.7-rc6:
Fixes a build issue without CONFIG_ARM_PMU and plugs pid leak on arm/arm64.
Commit d6a9996e84 ("powerpc/mm: vmalloc abstraction in preparation for
radix") turned kernel memory and IO addresses from #defined constants to
variables initialised at runtime.
On PA6T (pasemi) systems the setup_arch() machine call initialises the
onboard PCI-e root-ports, and uses pci_io_base to do this, which is now
before its value has been set, resulting in a panic early in boot before
console IO is initialised.
Move the pci_io_base initialisation to the same place as vmalloc ranges
are set (hash__early_init_mmu()/radix__early_init_mmu()) - this is the
earliest possible place we can initialise it.
Fixes: d6a9996e84 ("powerpc/mm: vmalloc abstraction in preparation for radix")
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Add #ifdef CONFIG_PCI, massage change log slightly]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently we have 2 segments that are bolted for the kernel linear
mapping (ie 0xc000... addresses). This is 0 to 1TB and also the kernel
stacks. Anything accessed outside of these regions may need to be
faulted in. (In practice machines with TM always have 1T segments)
If a machine has < 2TB of memory we never fault on the kernel linear
mapping as these two segments cover all physical memory. If a machine
has > 2TB of memory, there may be structures outside of these two
segments that need to be faulted in. This faulting can occur when
running as a guest as the hypervisor may remove any SLB that's not
bolted.
When we treclaim and trecheckpoint we have a window where we need to
run with the userspace GPRs. This means that we no longer have a valid
stack pointer in r1. For this window we therefore clear MSR RI to
indicate that any exceptions taken at this point won't be able to be
handled. This means that we can't take segment misses in this RI=0
window.
In this RI=0 region, we currently access the thread_struct for the
process being context switched to or from. This thread_struct access
may cause a segment fault since it's not guaranteed to be covered by
the two bolted segment entries described above.
We've seen this with a crash when running as a guest with > 2TB of
memory on PowerVM:
Unrecoverable exception 4100 at c00000000004f138
Oops: Unrecoverable exception, sig: 6 [#1]
SMP NR_CPUS=2048 NUMA pSeries
CPU: 1280 PID: 7755 Comm: kworker/1280:1 Tainted: G X 4.4.13-46-default #1
task: c000189001df4210 ti: c000189001d5c000 task.ti: c000189001d5c000
NIP: c00000000004f138 LR: 0000000010003a24 CTR: 0000000010001b20
REGS: c000189001d5f730 TRAP: 4100 Tainted: G X (4.4.13-46-default)
MSR: 8000000100001031 <SF,ME,IR,DR,LE> CR: 24000048 XER: 00000000
CFAR: c00000000004ed18 SOFTE: 0
GPR00: ffffffffc58d7b60 c000189001d5f9b0 00000000100d7d00 000000003a738288
GPR04: 0000000000002781 0000000000000006 0000000000000000 c0000d1f4d889620
GPR08: 000000000000c350 00000000000008ab 00000000000008ab 00000000100d7af0
GPR12: 00000000100d7ae8 00003ffe787e67a0 0000000000000000 0000000000000211
GPR16: 0000000010001b20 0000000000000000 0000000000800000 00003ffe787df110
GPR20: 0000000000000001 00000000100d1e10 0000000000000000 00003ffe787df050
GPR24: 0000000000000003 0000000000010000 0000000000000000 00003fffe79e2e30
GPR28: 00003fffe79e2e68 00000000003d0f00 00003ffe787e67a0 00003ffe787de680
NIP [c00000000004f138] restore_gprs+0xd0/0x16c
LR [0000000010003a24] 0x10003a24
Call Trace:
[c000189001d5f9b0] [c000189001d5f9f0] 0xc000189001d5f9f0 (unreliable)
[c000189001d5fb90] [c00000000001583c] tm_recheckpoint+0x6c/0xa0
[c000189001d5fbd0] [c000000000015c40] __switch_to+0x2c0/0x350
[c000189001d5fc30] [c0000000007e647c] __schedule+0x32c/0x9c0
[c000189001d5fcb0] [c0000000007e6b58] schedule+0x48/0xc0
[c000189001d5fce0] [c0000000000deabc] worker_thread+0x22c/0x5b0
[c000189001d5fd80] [c0000000000e7000] kthread+0x110/0x130
[c000189001d5fe30] [c000000000009538] ret_from_kernel_thread+0x5c/0xa4
Instruction dump:
7cb103a6 7cc0e3a6 7ca222a6 78a58402 38c00800 7cc62838 08860000 7cc000a6
38a00006 78c60022 7cc62838 0b060000 <e8c701a0> 7ccff120 e8270078 e8a70098
---[ end trace 602126d0a1dedd54 ]---
This fixes this by copying the required data from the thread_struct to
the stack before we clear MSR RI. Then once we clear RI, we only access
the stack, guaranteeing there's no segment miss.
We also tighten the region over which we set RI=0 on the treclaim()
path. This may have a slight performance impact since we're adding an
mtmsr instruction.
Fixes: 090b9284d7 ("powerpc/tm: Clear MSR RI in non-recoverable TM code")
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When calling eeh_rmv_device() in eeh_reset_device() for partial hotplug
case, @rmv_data instead of its address is the proper argument.
Otherwise, the stack frame is corrupted when writing to
@rmv_data (actually its address) in eeh_rmv_device(). It results in
kernel crash as observed.
This fixes the issue by passing @rmv_data, not its address to
eeh_rmv_device() in eeh_reset_device().
Fixes: 67086e32b5 ("powerpc/eeh: powerpc/eeh: Support error recovery for VF PE")
Reported-by: Pridhiviraj Paidipeddi <ppaidipe@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The test_fp_ctl function is used to test if a given value is a valid
floating-point control. The inline assembly in test_fp_ctl uses an
incorrect constraint for the 'orig_fpc' variable. If the compiler
chooses the same register for 'fpc' and 'orig_fpc' the test_fp_ctl()
function always returns true. This allows user space to trigger
kernel oopses with invalid floating-point control values on the
signal stack.
This problem has been introduced with git commit 4725c86055
"s390: fix save and restore of the floating-point-control register"
Cc: stable@vger.kernel.org # v3.13+
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This reverts commit 852ffd0f4e.
There are use cases where an intermediate boot kernel (1) uses kexec
to boot the final production kernel (2). For this scenario we should
provide the original boot information to the production kernel (2).
Therefore clearing the boot information during kexec() should not
be done.
Cc: stable@vger.kernel.org # v3.17+
Reported-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If CONFIG_ARC_DW2_UNWIND is disabled every time arc_unwind_core()
gets called following message gets printed in debug console:
----------------->8---------------
CONFIG_ARC_DW2_UNWIND needs to be enabled
----------------->8---------------
That message makes sense if user indeed wants to see a backtrace or
get nice function call-graphs in perf but what if user disabled
unwinder for the purpose? Why pollute his debug console?
So instead we'll warn user about possibly missing feature once and
let him decide if that was what he or she really wanted.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
With recent binutils update to support dwarf CFI pseudo-ops in gas, we
now get .eh_frame vs. .debug_frame. Although the call frame info is
exactly the same in both, the CIE differs, which the current kernel
unwinder can't cope with.
This broke both the kernel unwinder as well as loadable modules (latter
because of a new unhandled relo R_ARC_32_PCREL from .rela.eh_frame in
the module loader)
The ideal solution would be to switch unwinder to .eh_frame.
For now however we can make do by just ensureing .debug_frame is
generated by removing -fasynchronous-unwind-tables
.eh_frame generated with -gdwarf-2 -fasynchronous-unwind-tables
.debug_frame generated with -gdwarf-2
Fixes STAR 9001058196
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
I couldn't get Xen to boot a L2 HVM when it was nested under KVM - it was
getting a GP(0) on a rather unspecial vmread from Xen:
(XEN) ----[ Xen-4.7.0-rc x86_64 debug=n Not tainted ]----
(XEN) CPU: 1
(XEN) RIP: e008:[<ffff82d0801e629e>] vmx_get_segment_register+0x14e/0x450
(XEN) RFLAGS: 0000000000010202 CONTEXT: hypervisor (d1v0)
(XEN) rax: ffff82d0801e6288 rbx: ffff83003ffbfb7c rcx: fffffffffffab928
(XEN) rdx: 0000000000000000 rsi: 0000000000000000 rdi: ffff83000bdd0000
(XEN) rbp: ffff83000bdd0000 rsp: ffff83003ffbfab0 r8: ffff830038813910
(XEN) r9: ffff83003faf3958 r10: 0000000a3b9f7640 r11: ffff83003f82d418
(XEN) r12: 0000000000000000 r13: ffff83003ffbffff r14: 0000000000004802
(XEN) r15: 0000000000000008 cr0: 0000000080050033 cr4: 00000000001526e0
(XEN) cr3: 000000003fc79000 cr2: 0000000000000000
(XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: 0000 cs: e008
(XEN) Xen code around <ffff82d0801e629e> (vmx_get_segment_register+0x14e/0x450):
(XEN) 00 00 41 be 02 48 00 00 <44> 0f 78 74 24 08 0f 86 38 56 00 00 b8 08 68 00
(XEN) Xen stack trace from rsp=ffff83003ffbfab0:
...
(XEN) Xen call trace:
(XEN) [<ffff82d0801e629e>] vmx_get_segment_register+0x14e/0x450
(XEN) [<ffff82d0801f3695>] get_page_from_gfn_p2m+0x165/0x300
(XEN) [<ffff82d0801bfe32>] hvmemul_get_seg_reg+0x52/0x60
(XEN) [<ffff82d0801bfe93>] hvm_emulate_prepare+0x53/0x70
(XEN) [<ffff82d0801ccacb>] handle_mmio+0x2b/0xd0
(XEN) [<ffff82d0801be591>] emulate.c#_hvm_emulate_one+0x111/0x2c0
(XEN) [<ffff82d0801cd6a4>] handle_hvm_io_completion+0x274/0x2a0
(XEN) [<ffff82d0801f334a>] __get_gfn_type_access+0xfa/0x270
(XEN) [<ffff82d08012f3bb>] timer.c#add_entry+0x4b/0xb0
(XEN) [<ffff82d08012f80c>] timer.c#remove_entry+0x7c/0x90
(XEN) [<ffff82d0801c8433>] hvm_do_resume+0x23/0x140
(XEN) [<ffff82d0801e4fe7>] vmx_do_resume+0xa7/0x140
(XEN) [<ffff82d080164aeb>] context_switch+0x13b/0xe40
(XEN) [<ffff82d080128e6e>] schedule.c#schedule+0x22e/0x570
(XEN) [<ffff82d08012c0cc>] softirq.c#__do_softirq+0x5c/0x90
(XEN) [<ffff82d0801602c5>] domain.c#idle_loop+0x25/0x50
(XEN)
(XEN)
(XEN) ****************************************
(XEN) Panic on CPU 1:
(XEN) GENERAL PROTECTION FAULT
(XEN) [error_code=0000]
(XEN) ****************************************
Tracing my host KVM showed it was the one injecting the GP(0) when
emulating the VMREAD and checking the destination segment permissions in
get_vmx_mem_address():
3) | vmx_handle_exit() {
3) | handle_vmread() {
3) | nested_vmx_check_permission() {
3) | vmx_get_segment() {
3) 0.074 us | vmx_read_guest_seg_base();
3) 0.065 us | vmx_read_guest_seg_selector();
3) 0.066 us | vmx_read_guest_seg_ar();
3) 1.636 us | }
3) 0.058 us | vmx_get_rflags();
3) 0.062 us | vmx_read_guest_seg_ar();
3) 3.469 us | }
3) | vmx_get_cs_db_l_bits() {
3) 0.058 us | vmx_read_guest_seg_ar();
3) 0.662 us | }
3) | get_vmx_mem_address() {
3) 0.068 us | vmx_cache_reg();
3) | vmx_get_segment() {
3) 0.074 us | vmx_read_guest_seg_base();
3) 0.068 us | vmx_read_guest_seg_selector();
3) 0.071 us | vmx_read_guest_seg_ar();
3) 1.756 us | }
3) | kvm_queue_exception_e() {
3) 0.066 us | kvm_multiple_exception();
3) 0.684 us | }
3) 4.085 us | }
3) 9.833 us | }
3) + 10.366 us | }
Cross-checking the KVM/VMX VMREAD emulation code with the Intel Software
Developper Manual Volume 3C - "VMREAD - Read Field from Virtual-Machine
Control Structure", I found that we're enforcing that the destination
operand is NOT located in a read-only data segment or any code segment when
the L1 is in long mode - BUT that check should only happen when it is in
protected mode.
Shuffling the code a bit to make our emulation follow the specification
allows me to boot a Xen dom0 in a nested KVM and start HVM L2 guests
without problems.
Fixes: f9eb4af67c ("KVM: nVMX: VMX instructions: add checks for #GP/#SS exceptions")
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Eugene Korenevsky <ekorenevsky@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The host timer which emulates the guest LAPIC TSC deadline
timer has its expiration diminished by lapic_timer_advance_ns
nanoseconds. Therefore if, at wait_lapic_expire, a difference
larger than lapic_timer_advance_ns is encountered, delay at most
lapic_timer_advance_ns.
This fixes a problem where the guest can cause the host
to delay for large amounts of time.
Reported-by: Alan Jenkins <alan.christopher.jenkins@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the inline function nsec_to_cycles from x86.c to x86.h, as
the next patch uses it from lapic.c.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There is a generic function __pvclock_read_cycles to be used to get both
flags and cycles. For function pvclock_read_flags, it's useless to get
cycles value. To make this function be more effective, get this variable
flags directly in function.
Signed-off-by: Minfei Huang <mnghuan@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Function __pvclock_read_cycles is short enough, so there is no need to
have another function pvclock_get_nsec_offset to calculate tsc delta.
It's better to combine it into function __pvclock_read_cycles.
Remove useless variables in function __pvclock_read_cycles.
Signed-off-by: Minfei Huang <mnghuan@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Andy Lutomirski