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Linux kernel
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the problems which may result by upgrading your kernel.
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Pull libnvdimm fix from Dan Williams:
"Fix compilation for the new dax_supported() exported helper"
* tag 'libnvdimm-fixes-5.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
dax: Fix compilation for CONFIG_DAX && !CONFIG_FS_DAX
dax_supported() is defined whenever CONFIG_DAX is enabled. So dummy
implementation should be defined only in !CONFIG_DAX case, not in
!CONFIG_FS_DAX case.
Fixes: e2ec51282545 ("dm: Call proper helper to determine dax support")
Cc: <stable@vger.kernel.org>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull syscall tracing fix from Borislav Petkov:
"Fix the seccomp syscall rewriting so that trace and audit see the
rewritten syscall number, from Kees Cook"
* tag 'core_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
core/entry: Report syscall correctly for trace and audit
Pull objtool fix from Borislav Petkov:
"Fix noreturn detection for ignored sibling functions (Josh Poimboeuf)"
* tag 'objtool_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Fix noreturn detection for ignored functions
On v5.8 when doing seccomp syscall rewrites (e.g. getpid into getppid
as seen in the seccomp selftests), trace (and audit) correctly see the
rewritten syscall on entry and exit:
seccomp_bpf-1307 [000] .... 22974.874393: sys_enter: NR 110 (...
seccomp_bpf-1307 [000] .N.. 22974.874401: sys_exit: NR 110 = 1304
With mainline we see a mismatched enter and exit (the original syscall
is incorrectly visible on entry):
seccomp_bpf-1030 [000] .... 21.806766: sys_enter: NR 39 (...
seccomp_bpf-1030 [000] .... 21.806767: sys_exit: NR 110 = 1027
When ptrace or seccomp change the syscall, this needs to be visible to
trace and audit at that time as well. Update the syscall earlier so they
see the correct value.
Fixes: d88d59b64ca3 ("core/entry: Respect syscall number rewrites")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200912005826.586171-1-keescook@chromium.org
Pull locking fixes from Borislav Petkov:
"Two fixes from the locking/urgent pile:
- Fix lockdep's detection of "USED" <- "IN-NMI" inversions (Peter
Zijlstra)
- Make percpu-rwsem operations on the semaphore's ->read_count
IRQ-safe because it can be used in an IRQ context (Hou Tao)"
* tag 'locking_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/percpu-rwsem: Use this_cpu_{inc,dec}() for read_count
locking/lockdep: Fix "USED" <- "IN-NMI" inversions
When a function is annotated with STACK_FRAME_NON_STANDARD, objtool
doesn't validate its code paths. It also skips sibling call detection
within the function.
But sibling call detection is actually needed for the case where the
ignored function doesn't have any return instructions. Otherwise
objtool naively marks the function as implicit static noreturn, which
affects the reachability of its callers, resulting in "unreachable
instruction" warnings.
Fix it by just enabling sibling call detection for ignored functions.
The 'insn->ignore' check in add_jump_destinations() is no longer needed
after
e6da9567959e ("objtool: Don't use ignore flag for fake jumps").
Fixes the following warning:
arch/x86/kvm/vmx/vmx.o: warning: objtool: vmx_handle_exit_irqoff()+0x142: unreachable instruction
which triggers on an allmodconfig with CONFIG_GCOV_KERNEL unset.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/5b1e2536cdbaa5246b60d7791b76130a74082c62.1599751464.git.jpoimboe@redhat.com
Pull EFI fix from Borislav Petkov:
"Ensure that the EFI bootloader control module only probes successfully
on systems that support the EFI SetVariable runtime service"
[ Tag and commit from Ard Biesheuvel, forwarded by Borislav ]
* tag 'efi-urgent-for-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: efibc: check for efivars write capability
The __this_cpu*() accessors are (in general) IRQ-unsafe which, given
that percpu-rwsem is a blocking primitive, should be just fine.
However, file_end_write() is used from IRQ context and will cause
load-store issues on architectures where the per-cpu accessors are not
natively irq-safe.
Fix it by using the IRQ-safe this_cpu_*() for operations on
read_count. This will generate more expensive code on a number of
platforms, which might cause a performance regression for some of the
other percpu-rwsem users.
If any such is reported, we can consider alternative solutions.
Fixes: 70fe2f48152e ("aio: fix freeze protection of aio writes")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/20200915140750.137881-1-houtao1@huawei.com
Pull ARM SoC fixes from Olof Johansson:
"A collection of fixes I've been accruing over the last few weeks, none
of them have been severe enough to warrant flushing the queue but it's
been long enough now that it's a good idea to send them in.
A handful of them are fixups for QSPI DT/bindings/compatibles, some
smaller fixes for system DMA clock control and TMU interrupts on i.MX,
a handful of fixes for OMAP, including a fix for DSI (display) on
omap5"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (27 commits)
arm64: dts: ns2: Fixed QSPI compatible string
ARM: dts: BCM5301X: Fixed QSPI compatible string
ARM: dts: NSP: Fixed QSPI compatible string
ARM: dts: bcm: HR2: Fixed QSPI compatible string
dt-bindings: spi: Fix spi-bcm-qspi compatible ordering
ARM: dts: imx6sx: fix the pad QSPI1B_SCLK mux mode for uart3
arm64: dts: imx8mp: correct sdma1 clk setting
arm64: dts: imx8mq: Fix TMU interrupt property
ARM: dts: imx7d-zii-rmu2: fix rgmii phy-mode for ksz9031 phy
ARM: dts: vfxxx: Add syscon compatible with OCOTP
ARM: dts: imx6q-logicpd: Fix broken PWM
arm64: dts: imx: Add missing imx8mm-beacon-kit.dtb to build
ARM: dts: imx6q-prtwd2: Remove unneeded i2c unit name
ARM: dts: imx6qdl-gw51xx: Remove unneeded #address-cells/#size-cells
ARM: dts: imx7ulp: Correct gpio ranges
ARM: dts: ls1021a: fix QuadSPI-memory reg range
arm64: defconfig: Enable ptn5150 extcon driver
arm64: defconfig: Enable USB gadget with configfs
ARM: configs: Update Integrator defconfig
ARM: dts: omap5: Fix DSI base address and clocks
...
Pull x86 fixes from Borislav Petkov:
- A defconfig fix (Daniel Díaz)
- Disable relocation relaxation for the compressed kernel when not
built as -pie as in that case kernels built with clang and linked
with LLD fail to boot due to the linker optimizing some instructions
in non-PIE form; the gory details in the commit message (Arvind
Sankar)
- A fix for the "bad bp value" warning issued by the frame-pointer
unwinder (Josh Poimboeuf)
* tag 'x86_urgent_for_v5.9_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/unwind/fp: Fix FP unwinding in ret_from_fork
x86/boot/compressed: Disable relocation relaxation
x86/defconfigs: Explicitly unset CONFIG_64BIT in i386_defconfig
Branden reports that commit
f88814cc2578c1 ("efi/efivars: Expose RT service availability via efivars abstraction")
regresses UEFI platforms that implement GetVariable but not SetVariable
when booting kernels that have EFIBC (bootloader control) enabled.
The reason is that EFIBC is a user of the efivars abstraction, which was
updated to permit users that rely only on the read capability, but not on
the write capability. EFIBC is in the latter category, so it has to check
explicitly whether efivars supports writes.
Fixes: f88814cc2578c1 ("efi/efivars: Expose RT service availability via efivars abstraction")
Tested-by: Branden Sherrell <sherrellbc@gmail.com>
Link: https://lore.kernel.org/linux-efi/AE217103-C96F-4AFC-8417-83EC11962004@gmail.com/
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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