Explicitly zero out quadrant and invalid instead of inheriting them from
the root_mmu. Functionally, this patch is a nop as we (should) never
set quadrant for a direct mapped (EPT) root_mmu and nested EPT is only
allowed if EPT is used for L1, and the root_mmu will never be invalid at
this point.
Explicitly setting flags sets the stage for repurposing the legacy
paging bits in role, e.g. nxe, cr0_wp, and sm{a,e}p_andnot_wp, at which
point 'smm' would be the only flag to be inherited from root_mmu.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
"spi-cs-high" is going to be specified in child node of an SPI
controller's representing attached SPI device, so change the code to
look for it there, instead of checking parent node.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
SPI GPIO device has more than just "cs-gpio" property in its node and
would request those GPIOs as a part of its initialization. To avoid
applying CS-specific quirk to all of them add a check to make sure
that propname is "cs-gpios".
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
&cpu_info.x86_capability is __percpu, and the second argument of
x86_this_cpu_test_bit() is expected to be __percpu. Don't cast the
__percpu away and then implicitly add it again. This gets rid of 106
lines of sparse warnings with the kernel config I'm using.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190328154948.152273-1-jannh@google.com
The marshalling of AFS.StoreData, AFS.StoreData64 and YFS.StoreData64 calls
generated by ->setattr() ops for the purpose of expanding a file is
incorrect due to older documentation incorrectly describing the way the RPC
'FileLength' parameter is meant to work.
The older documentation says that this is the length the file is meant to
end up at the end of the operation; however, it was never implemented this
way in any of the servers, but rather the file is truncated down to this
before the write operation is effected, and never expanded to it (and,
indeed, it was renamed to 'TruncPos' in 2014).
Fix this by setting the position parameter to the new file length and doing
a zero-lengh write there.
The bug causes Xwayland to SIGBUS due to unexpected non-expansion of a file
it then mmaps. This can be tested by giving the following test program a
filename in an AFS directory:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
int main(int argc, char *argv[])
{
char *p;
int fd;
if (argc != 2) {
fprintf(stderr,
"Format: test-trunc-mmap <file>\n");
exit(2);
}
fd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC);
if (fd < 0) {
perror(argv[1]);
exit(1);
}
if (ftruncate(fd, 0x140008) == -1) {
perror("ftruncate");
exit(1);
}
p = mmap(NULL, 4096, PROT_READ | PROT_WRITE,
MAP_SHARED, fd, 0);
if (p == MAP_FAILED) {
perror("mmap");
exit(1);
}
p[0] = 'a';
if (munmap(p, 4096) < 0) {
perror("munmap");
exit(1);
}
if (close(fd) < 0) {
perror("close");
exit(1);
}
exit(0);
}
Fixes: 31143d5d51 ("AFS: implement basic file write support")
Reported-by: Jonathan Billings <jsbillin@umich.edu>
Tested-by: Jonathan Billings <jsbillin@umich.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update the mount API docs to reflect recent changes to the code.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fix early free of the channel program in vfio
- On AP device removal make sure that all messages are flushed
with the driver still attached that queued the message
- Limit brk randomization to 32MB to reduce the chance that the
heap of ld.so is placed after the main stack
- Add a rolling average for the steal time of a CPU, this will be
needed for KVM to decide when to do busy waiting
- Fix a warning in the CPU-MF code
- Add a notification handler for AP configuration change to react
faster to new AP devices
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Merge tag 's390-5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky:
"Improvements and bug fixes for 5.1-rc2:
- Fix early free of the channel program in vfio
- On AP device removal make sure that all messages are flushed with
the driver still attached that queued the message
- Limit brk randomization to 32MB to reduce the chance that the heap
of ld.so is placed after the main stack
- Add a rolling average for the steal time of a CPU, this will be
needed for KVM to decide when to do busy waiting
- Fix a warning in the CPU-MF code
- Add a notification handler for AP configuration change to react
faster to new AP devices"
* tag 's390-5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/cpumf: Fix warning from check_processor_id
zcrypt: handle AP Info notification from CHSC SEI command
vfio: ccw: only free cp on final interrupt
s390/vtime: steal time exponential moving average
s390/zcrypt: revisit ap device remove procedure
s390: limit brk randomization to 32MB
A couple of minor fixes only for now
- Incorrect DMA channels on Renesas R-Car
- Broadcom bcm2835 error handling fixes
- Kconfig dependency fixes for bcm2835 and davinci
- CPU idle wakeup fix for i.MX6
- MMC regression on Tegra186
- Incorrect phy settings on one imx board
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Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC fixes from Arnd Bergmann:
"A couple of minor fixes only for now
- fix for incorrect DMA channels on Renesas R-Car
- Broadcom bcm2835 error handling fixes
- Kconfig dependency fixes for bcm2835 and davinci
- CPU idle wakeup fix for i.MX6
- MMC regression on Tegra186
- fix incorrect phy settings on one imx board"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
arm64: tegra: Disable CQE Support for SDMMC4 on Tegra186
ARM: dts: nomadik: Fix polarity of SPI CS
ARM: davinci: fix build failure with allnoconfig
ARM: imx_v4_v5_defconfig: enable PWM driver
ARM: imx_v6_v7_defconfig: continue compiling the pwm driver
ARM: dts: imx6dl-yapp4: Use correct pseudo PHY address for the switch
ARM: dts: imx6qdl: Fix typo in imx6qdl-icore-rqs.dtsi
ARM: dts: imx6ull: Use the correct style for SPDX License Identifier
ARM: dts: pfla02: increase phy reset duration
ARM: imx6q: cpuidle: fix bug that CPU might not wake up at expected time
ARM: imx51: fix a leaked reference by adding missing of_node_put
ARM: dts: imx6dl-yapp4: Use rgmii-id phy mode on the cpu port
arm64: bcm2835: Add missing dependency on MFD_CORE.
ARM: dts: bcm283x: Fix hdmi hpd gpio pull
soc: bcm: bcm2835-pm: Fix error paths of initialization.
soc: bcm: bcm2835-pm: Fix PM_IMAGE_PERI power domain support.
arm64: dts: renesas: r8a774c0: Fix SCIF5 DMA channels
arm64: dts: renesas: r8a77990: Fix SCIF5 DMA channels
Fix commit 56067812d5 ("kbuild: modversions: add infrastructure for
emitting relative CRCs") where CRCs are interpreted in host byte order
rather than proper kernel byte order. The bug is conditional on
CONFIG_MODULE_REL_CRCS.
For example, when loading a BE module into a BE kernel compiled with a LE
system, the error "disagrees about version of symbol module_layout" is
produced. A message such as "Found checksum D7FA6856 vs module 5668FAD7"
will be given with debug enabled, which indicates an obvious endian
problem within __kcrctab within the kernel image.
The general solution is to use the macro TO_NATIVE, as is done in
similar cases throughout modpost.c. With this correction it has been
verified that a BE kernel compiled with a LE system accepts BE modules.
This change has also been verified with a LE kernel compiled with a LE
system, in which case TO_NATIVE returns its value unmodified since the
byte orders match. This is by far the common case.
Fixes: 56067812d5 ("kbuild: modversions: add infrastructure for emitting relative CRCs")
Signed-off-by: Fredrik Noring <noring@nocrew.org>
Cc: stable@vger.kernel.org
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Summary was copy and pasted from array_size.cocci.
Signed-off-by: Michael Stefaniuc <mstefani@mykolab.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
CC_FLAGS_FTRACE may contain trailing whitespace that interferes with
findstring.
For example, commit 6977f95e63 ("powerpc: avoid -mno-sched-epilog on
GCC 4.9 and newer") introduced a change such that on my ppc64le box,
CC_FLAGS_FTRACE="-pg -mprofile-kernel ". (Note the trailing space.)
When cmd_record_mcount is now invoked, findstring fails as the ftrace
flags were found at very end of _c_flags, without the trailing space.
_c_flags=" ... -pg -mprofile-kernel"
CC_FLAGS_FTRACE="-pg -mprofile-kernel "
^
findstring is looking for this extra space
Remove the redundant whitespaces from CC_FLAGS_FTRACE in
cmd_record_mcount to avoid this problem.
[masahiro.yamada: This issue only happens in the released versions
of GNU Make. CC_FLAGS_FTRACE will not contain the trailing space if
you use the latest GNU Make, which contains commit b90fabc8d6f3
("* NEWS: Do not insert a space during '+=' if the value is empty.") ]
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com> (refactoring)
Fixes: 6977f95e63 ("powerpc: avoid -mno-sched-epilog on GCC 4.9 and newer").
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Commit 3a51ff3442 ("kbuild: gitignore output directory") seemed to
bother people who version-control output directories.
Andre Przywara says:
"Unfortunately this breaks my setup, because I keep a totally separate
git repository in my build directories to track (various versions of)
.config. So .gitignore there is carefully crafted to ignore most build
artefacts, but not .config, for instance."
Link: https://lkml.org/lkml/2019/3/22/1819
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
When Make recurses to the top Makefile with sub-make-done unset,
the code block surrounded by 'ifneq ($(sub-make-done),1) ... endif'
is parsed multiple times. This happens for in-tree building of
include/config/auto.conf, *-pkg, etc. with GNU Make 4.x.
This is a slight regression by commit 688931a5ad ("kbuild: skip
sub-make for in-tree build with GNU Make 4.x") in terms of performance
since that code block contains one $(shell ...) invocation.
Fix it by exporting the variable irrespective of sub-make being run.
I renamed it because GNU Make cannot properly export variables
containing hyphens. This is probably a bug of GNU Make, and the issue
in Kbuild had already been reported by commit 2bfbe7881e ("kbuild:
Do not use hyphen in exported variable name").
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Don't complain about a return when this function returns "&pdev->dev".
Fixes: da9cfb87a4 ("coccinelle: semantic code search for missing put_device()")
Reported-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
When CONFIG_VMAP_STACK=y, __pa() returns incorrect physical address for
a stack virtual address. Stack DMA buffers must be avoided.
Signed-off-by: raymond pang <raymondpangxd@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
GT VEBOX DISABLE is only 4 bits wide but it was using a 8 bits wide
mask, the remaning reserved bits is set to 0 causing 4 more
nonexistent VEBOX engines being detected as enabled, triggering the
BUG_ON() because of mismatch between vebox_mask and newly added
VEBOX_MASK().
[ 64.081621] [drm:intel_device_info_init_mmio [i915]] vdbox enable: 0005, instances: 0005
[ 64.081763] [drm:intel_device_info_init_mmio [i915]] vebox enable: 00f1, instances: 0001
[ 64.081825] intel_device_info_init_mmio:925 GEM_BUG_ON(vebox_mask != ({ unsigned int first__ = (VECS0); unsigned int count__ = (2); ((&(dev_priv)->__info)->engine_mask & (((~0UL) - (1UL << (first__)) + 1) & (~0UL >> (64 - 1 - (first__ + count__ - 1))))) >> first__; }))
[ 64.082047] ------------[ cut here ]------------
[ 64.082054] kernel BUG at drivers/gpu/drm/i915/intel_device_info.c:925!
BSpec: 20680
Fixes: 26376a7e74 ("drm/i915/icl: Check for fused-off VDBOX and VEBOX instances")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326230223.26336-1-jose.souza@intel.com
(cherry picked from commit 547fcf9b1c)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
kernel/futex_compat.c was recently removed, but it's still in the
MAINTAINERS file. Remove it there as well.
Fixes: 04e7712f44 ("y2038: futex: Move compat implementation into futex.c")
Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Some comments in virt/kvm/arm/mmu.c are outdated. Update them to
reflect the current state of the code.
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[maz: commit message tidy-up]
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
valid_phys_addr_range() is used to sanity check the physical address range
of an operation, e.g., access to /dev/mem. It uses __pa(high_memory)
internally.
If memory is populated at the end of the physical address space, then
__pa(high_memory) is outside of the physical address space because:
high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
For the comparison in valid_phys_addr_range() this is not an issue, but if
CONFIG_DEBUG_VIRTUAL is enabled, __pa() maps to __phys_addr(), which
verifies that the resulting physical address is within the valid physical
address space of the CPU. So in the case that memory is populated at the
end of the physical address space, this is not true and triggers a
VIRTUAL_BUG_ON().
Use __pa(high_memory - 1) to prevent the conversion from going beyond
the end of valid physical addresses.
Fixes: be62a32044 ("x86/mm: Limit mmap() of /dev/mem to valid physical addresses")
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Craig Bergstrom <craigb@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Cc: Sean Young <sean@mess.org>
Link: https://lkml.kernel.org/r/20190326001817.15413-2-rcampbell@nvidia.com
Commit ce02ef06fc ("x86, retpolines: Raise limit for generating indirect
calls from switch-case") raised the limit under retpolines to 20 switch
cases where gcc would only then start to emit jump tables, and therefore
effectively disabling the emission of slow indirect calls in this area.
After this has been brought to attention to gcc folks [0], Martin Liska
has then fixed gcc to align with clang by avoiding to generate switch jump
tables entirely under retpolines. This is taking effect in gcc starting
from stable version 8.4.0. Given kernel supports compilation with older
versions of gcc where the fix is not being available or backported anymore,
we need to keep the extra KBUILD_CFLAGS around for some time and generally
set the -fno-jump-tables to align with what more recent gcc is doing
automatically today.
More than 20 switch cases are not expected to be fast-path critical, but
it would still be good to align with gcc behavior for versions < 8.4.0 in
order to have consistency across supported gcc versions. vmlinux size is
slightly growing by 0.27% for older gcc. This flag is only set to work
around affected gcc, no change for clang.
[0] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86952
Suggested-by: Martin Liska <mliska@suse.cz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Björn Töpel<bjorn.topel@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Link: https://lkml.kernel.org/r/20190325135620.14882-1-daniel@iogearbox.net
The SMT disable 'nosmt' command line argument is not working properly when
CONFIG_HOTPLUG_CPU is disabled. The teardown of the sibling CPUs which are
required to be brought up due to the MCE issues, cannot work. The CPUs are
then kept in a half dead state.
As the 'nosmt' functionality has become popular due to the speculative
hardware vulnerabilities, the half torn down state is not a proper solution
to the problem.
Enforce CONFIG_HOTPLUG_CPU=y when SMP is enabled so the full operation is
possible.
Reported-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Rik van Riel <riel@surriel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Micheal Kelley <michael.h.kelley@microsoft.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190326163811.598166056@linutronix.de
Tianyu reported a crash in a CPU hotplug teardown callback when booting a
kernel which has CONFIG_HOTPLUG_CPU disabled with the 'nosmt' boot
parameter.
It turns out that the SMP=y CONFIG_HOTPLUG_CPU=n case has been broken
forever in case that a bringup callback fails. Unfortunately this issue was
not recognized when the CPU hotplug code was reworked, so the shortcoming
just stayed in place.
When a bringup callback fails, the CPU hotplug code rolls back the
operation and takes the CPU offline.
The 'nosmt' command line argument uses a bringup failure to abort the
bringup of SMT sibling CPUs. This partial bringup is required due to the
MCE misdesign on Intel CPUs.
With CONFIG_HOTPLUG_CPU=y the rollback works perfectly fine, but
CONFIG_HOTPLUG_CPU=n lacks essential mechanisms to exercise the low level
teardown of a CPU including the synchronizations in various facilities like
RCU, NOHZ and others.
As a consequence the teardown callbacks which must be executed on the
outgoing CPU within stop machine with interrupts disabled are executed on
the control CPU in interrupt enabled and preemptible context causing the
kernel to crash and burn. The pre state machine code has a different
failure mode which is more subtle and resulting in a less obvious use after
free crash because the control side frees resources which are still in use
by the undead CPU.
But this is not a x86 only problem. Any architecture which supports the
SMP=y HOTPLUG_CPU=n combination suffers from the same issue. It's just less
likely to be triggered because in 99.99999% of the cases all bringup
callbacks succeed.
The easy solution of making HOTPLUG_CPU mandatory for SMP is not working on
all architectures as the following architectures have either no hotplug
support at all or not all subarchitectures support it:
alpha, arc, hexagon, openrisc, riscv, sparc (32bit), mips (partial).
Crashing the kernel in such a situation is not an acceptable state
either.
Implement a minimal rollback variant by limiting the teardown to the point
where all regular teardown callbacks have been invoked and leave the CPU in
the 'dead' idle state. This has the following consequences:
- the CPU is brought down to the point where the stop_machine takedown
would happen.
- the CPU stays there forever and is idle
- The CPU is cleared in the CPU active mask, but not in the CPU online
mask which is a legit state.
- Interrupts are not forced away from the CPU
- All facilities which only look at online mask would still see it, but
that is the case during normal hotplug/unplug operations as well. It's
just a (way) longer time frame.
This will expose issues, which haven't been exposed before or only seldom,
because now the normally transient state of being non active but online is
a permanent state. In testing this exposed already an issue vs. work queues
where the vmstat code schedules work on the almost dead CPU which ends up
in an unbound workqueue and triggers 'preemtible context' warnings. This is
not a problem of this change, it merily exposes an already existing issue.
Still this is better than crashing fully without a chance to debug it.
This is mainly thought as workaround for those architectures which do not
support HOTPLUG_CPU. All others should enforce HOTPLUG_CPU for SMP.
Fixes: 2e1a3483ce ("cpu/hotplug: Split out the state walk into functions")
Reported-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Rik van Riel <riel@surriel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Micheal Kelley <michael.h.kelley@microsoft.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190326163811.503390616@linutronix.de
The rework of the watchdog core to use cpu_stop_work broke the watchdog
cpumask on CPU hotplug.
The watchdog_enable/disable() functions are now called unconditionally from
the hotplug callback, i.e. even on CPUs which are not in the watchdog
cpumask. As a consequence the watchdog can become unstoppable.
Only invoke them when the plugged CPU is in the watchdog cpumask.
Fixes: 9cf57731b6 ("watchdog/softlockup: Replace "watchdog/%u" threads with cpu_stop_work")
Reported-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1903262245490.1789@nanos.tec.linutronix.de
Free the priv structure only after we are done using it.
Fixes: 1690d8bb91 ("cpufreq: scpi/scmi: Fix freeing of dynamic OPPs")
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Cc: 4.20+ <stable@vger.kernel.org> # 4.20+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Function __hw_perf_event_init() used a CPU variable without
ensuring CPU preemption has been disabled. This caused the
following warning in the kernel log:
[ 7.277085] BUG: using smp_processor_id() in preemptible
[00000000] code: cf-csdiag/1892
[ 7.277111] caller is cf_diag_event_init+0x13a/0x338
[ 7.277122] CPU: 10 PID: 1892 Comm: cf-csdiag Not tainted
5.0.0-20190318.rc0.git0.9e1a11e0f602.300.fc29.s390x+debug #1
[ 7.277131] Hardware name: IBM 2964 NC9 712 (LPAR)
[ 7.277139] Call Trace:
[ 7.277150] ([<000000000011385a>] show_stack+0x82/0xd0)
[ 7.277161] [<0000000000b7a71a>] dump_stack+0x92/0xd0
[ 7.277174] [<00000000007b7e9c>] check_preemption_disabled+0xe4/0x100
[ 7.277183] [<00000000001228aa>] cf_diag_event_init+0x13a/0x338
[ 7.277195] [<00000000002cf3aa>] perf_try_init_event+0x72/0xf0
[ 7.277204] [<00000000002d0bba>] perf_event_alloc+0x6fa/0xce0
[ 7.277214] [<00000000002dc4a8>] __s390x_sys_perf_event_open+0x398/0xd50
[ 7.277224] [<0000000000b9e8f0>] system_call+0xdc/0x2d8
[ 7.277233] 2 locks held by cf-csdiag/1892:
[ 7.277241] #0: 00000000976f5510 (&sig->cred_guard_mutex){+.+.},
at: __s390x_sys_perf_event_open+0xd2e/0xd50
[ 7.277257] #1: 00000000363b11bd (&pmus_srcu){....},
at: perf_event_alloc+0x52e/0xce0
The variable is now accessed in proper context. Use
get_cpu_var()/put_cpu_var() pair to disable
preemption during access.
As the hardware authorization settings apply to all CPUs, it
does not matter which CPU is used to check the authorization setting.
Remove the event->count assignment. It is not needed as function
perf_event_alloc() allocates memory for the event with kzalloc() and
thus count is already set to zero.
Fixes: fe5908bccc ("s390/cpum_cf_diag: Add support for s390 counter facility diagnostic trace")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Lorenz Messtechnik has a device that is controlled by the cp210x driver,
so add the device id to the driver. The device id was provided by
Silicon-Labs for the devices from this vendor.
Reported-by: Uli <t9cpu@web.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
No change to functionality. Simply make transport event messages a little
clearer, and rework CRQ format enums such that we have separate enums for
INIT messages and XPORT events.
[mkp: typo]
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Status and error codes are returned in big endian from the VIOS. The values
are translated into a human readable format when logged, but the values are
also logged. This patch byte swaps those values so that they are consistent
between BE and LE platforms.
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The VIOS uses the SCSI_ERROR class to report PRLI failures. These errors
are indicated with the combination of a IBMVFC_FC_SCSI_ERROR return status
and 0x8000 error code. Add these codes to cmd_status[] with appropriate
human readable error message.
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The text of messages logged with ibmvfc_log_error() always contain the term
"failed". In the case of cancelled commands during EH they are reported
back by the VIOS using error codes. This can be confusing to somebody
looking at these log messages as to whether a command was successfully
cancelled. The following real log message for example it is unclear if the
transaction was actaully cancelled.
<6>sd 0:0:1:1: Cancelling outstanding commands.
<3>sd 0:0:1:1: [sde] Command (28) failed: transaction cancelled (2:6) flags: 0 fcp_rsp: 0, resid=0, scsi_status: 0
Remove prefixing of "failed" to all error logged messages. The
ibmvfc_log_error() function translates the returned error/status codes to a
human readable message already.
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If an incoming ELS of type RSCN contains more than one element, zfcp
suboptimally causes repeated erp trigger NOP trace records for each
previously failed port. These could be ports that went away. It loops over
each RSCN element, and for each of those in an inner loop over all
zfcp_ports.
The trigger to recover failed ports should be just the reception of some
RSCN, no matter how many elements it has. So we can loop over failed ports
separately, and only then loop over each RSCN element to handle the
non-failed ports.
The call chain was:
zfcp_fc_incoming_rscn
for (i = 1; i < no_entries; i++)
_zfcp_fc_incoming_rscn
list_for_each_entry(port, &adapter->port_list, list)
if (masked port->d_id match) zfcp_fc_test_link
if (!port->d_id) zfcp_erp_port_reopen "fcrscn1" <===
In order the reduce the "flooding" of the REC trace area in such cases, we
factor out handling the failed ports to be outside of the entries loop:
zfcp_fc_incoming_rscn
if (no_entries > 1) <===
list_for_each_entry(port, &adapter->port_list, list) <===
if (!port->d_id) zfcp_erp_port_reopen "fcrscn1" <===
for (i = 1; i < no_entries; i++)
_zfcp_fc_incoming_rscn
list_for_each_entry(port, &adapter->port_list, list)
if (masked port->d_id match) zfcp_fc_test_link
Abbreviated example trace records before this code change:
Tag : fcrscn1
WWPN : 0x500507630310d327
ERP want : 0x02
ERP need : 0x02
Tag : fcrscn1
WWPN : 0x500507630310d327
ERP want : 0x02
ERP need : 0x00 NOP => superfluous trace record
The last trace entry repeats if there are more than 2 RSCN elements.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Suppose more than one non-NPIV FCP device is active on the same channel.
Send I/O to storage and have some of the pending I/O run into a SCSI
command timeout, e.g. due to bit errors on the fibre. Now the error
situation stops. However, we saw FCP requests continue to timeout in the
channel. The abort will be successful, but the subsequent TUR fails.
Scsi_eh starts. The LUN reset fails. The target reset fails. The host
reset only did an FCP device recovery. However, for non-NPIV FCP devices,
this does not close and reopen ports on the SAN-side if other non-NPIV FCP
device(s) share the same open ports.
In order to resolve the continuing FCP request timeouts, we need to
explicitly close and reopen ports on the SAN-side.
This was missing since the beginning of zfcp in v2.6.0 history commit
ea127f975424 ("[PATCH] s390 (7/7): zfcp host adapter.").
Note: The FSF requests for forced port reopen could run into FSF request
timeouts due to other reasons. This would trigger an internal FCP device
recovery. Pending forced port reopen recoveries would get dismissed. So
some ports might not get fully reopened during this host reset handler.
However, subsequent I/O would trigger the above described escalation and
eventually all ports would be forced reopen to resolve any continuing FCP
request timeouts due to earlier bit errors.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: <stable@vger.kernel.org> #3.0+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
An already deleted SCSI device can exist on the Scsi_Host and remain there
because something still holds a reference. A new SCSI device with the same
H:C:T:L and FCP device, target port WWPN, and FCP LUN can be created. When
we try to unblock an rport, we still find the deleted SCSI device and
return early because the zfcp_scsi_dev of that SCSI device is not
ZFCP_STATUS_COMMON_UNBLOCKED. Hence we miss to unblock the rport, even if
the new proper SCSI device would be in good state.
Therefore, skip deleted SCSI devices when iterating the sdevs of the shost.
[cf. __scsi_device_lookup{_by_target}() or scsi_device_get()]
The following abbreviated trace sequence can indicate such problem:
Area : REC
Tag : ersfs_3
LUN : 0x4045400300000000
WWPN : 0x50050763031bd327
LUN status : 0x40000000 not ZFCP_STATUS_COMMON_UNBLOCKED
Ready count : n not incremented yet
Running count : 0x00000000
ERP want : 0x01
ERP need : 0xc1 ZFCP_ERP_ACTION_NONE
Area : REC
Tag : ersfs_3
LUN : 0x4045400300000000
WWPN : 0x50050763031bd327
LUN status : 0x41000000
Ready count : n+1
Running count : 0x00000000
ERP want : 0x01
ERP need : 0x01
...
Area : REC
Level : 4 only with increased trace level
Tag : ertru_l
LUN : 0x4045400300000000
WWPN : 0x50050763031bd327
LUN status : 0x40000000
Request ID : 0x0000000000000000
ERP status : 0x01800000
ERP step : 0x1000
ERP action : 0x01
ERP count : 0x00
NOT followed by a trace record with tag "scpaddy"
for WWPN 0x50050763031bd327.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 6f2ce1c6af ("scsi: zfcp: fix rport unblock race with LUN recovery")
Cc: <stable@vger.kernel.org> #2.6.32+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Commit a83da8a450 ("scsi: sd: Optimal I/O size should be a multiple
of physical block size") split one conditional into several separate
statements in an effort to provide more accurate warning messages when
a device reports a nonsensical value. However, this reorganization
accidentally dropped the precondition of the reported value being
larger than zero. This lead to a warning getting emitted on devices
that do not report an optimal I/O size at all.
Remain silent if a device does not report an optimal I/O size.
Fixes: a83da8a450 ("scsi: sd: Optimal I/O size should be a multiple of physical block size")
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: <stable@vger.kernel.org>
Reported-by: Hussam Al-Tayeb <ht990332@gmx.com>
Tested-by: Hussam Al-Tayeb <ht990332@gmx.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The scsi_end_request() function calls scsi_cmd_to_driver() indirectly and
hence needs the disk->private_data pointer. Avoid that that pointer is
cleared before all affected I/O requests have finished. This patch avoids
that the following crash occurs:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Call trace:
scsi_mq_uninit_cmd+0x1c/0x30
scsi_end_request+0x7c/0x1b8
scsi_io_completion+0x464/0x668
scsi_finish_command+0xbc/0x160
scsi_eh_flush_done_q+0x10c/0x170
sas_scsi_recover_host+0x84c/0xa98 [libsas]
scsi_error_handler+0x140/0x5b0
kthread+0x100/0x12c
ret_from_fork+0x10/0x18
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reported-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use dd to test a SCSI device:
1. echo "blocked" >/sys/block/sda/device/state
2. dd if=/dev/sda of=/mnt/t.log bs=1M count=10
3. echo "running" >/sys/block/sda/device/state
dd should finish this work after step 3, but it hangs.
After step2, the call chain is this:
blk_mq_dispatch_rq_list-->scsi_queue_rq-->prep_to_mq
prep_to_mq will return BLK_STS_RESOURCE, and scsi_queue_rq will
transition it to BLK_STS_DEV_RESOURCE which means that driver can
guarantee that IO dispatch will be triggered in future when the
resource is available. Need to follow the rule if we set the device
state to running.
[mkp: tweaked commit description and code comment as suggested by Bart]
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Pull networking fixes from David Miller:
"Fixes here and there, a couple new device IDs, as usual:
1) Fix BQL race in dpaa2-eth driver, from Ioana Ciornei.
2) Fix 64-bit division in iwlwifi, from Arnd Bergmann.
3) Fix documentation for some eBPF helpers, from Quentin Monnet.
4) Some UAPI bpf header sync with tools, also from Quentin Monnet.
5) Set descriptor ownership bit at the right time for jumbo frames in
stmmac driver, from Aaro Koskinen.
6) Set IFF_UP properly in tun driver, from Eric Dumazet.
7) Fix load/store doubleword instruction generation in powerpc eBPF
JIT, from Naveen N. Rao.
8) nla_nest_start() return value checks all over, from Kangjie Lu.
9) Fix asoc_id handling in SCTP after the SCTP_*_ASSOC changes this
merge window. From Marcelo Ricardo Leitner and Xin Long.
10) Fix memory corruption with large MTUs in stmmac, from Aaro
Koskinen.
11) Do not use ipv4 header for ipv6 flows in TCP and DCCP, from Eric
Dumazet.
12) Fix topology subscription cancellation in tipc, from Erik Hugne.
13) Memory leak in genetlink error path, from Yue Haibing.
14) Valid control actions properly in packet scheduler, from Davide
Caratti.
15) Even if we get EEXIST, we still need to rehash if a shrink was
delayed. From Herbert Xu.
16) Fix interrupt mask handling in interrupt handler of r8169, from
Heiner Kallweit.
17) Fix leak in ehea driver, from Wen Yang"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (168 commits)
dpaa2-eth: fix race condition with bql frame accounting
chelsio: use BUG() instead of BUG_ON(1)
net: devlink: skip info_get op call if it is not defined in dumpit
net: phy: bcm54xx: Encode link speed and activity into LEDs
tipc: change to check tipc_own_id to return in tipc_net_stop
net: usb: aqc111: Extend HWID table by QNAP device
net: sched: Kconfig: update reference link for PIE
net: dsa: qca8k: extend slave-bus implementations
net: dsa: qca8k: remove leftover phy accessors
dt-bindings: net: dsa: qca8k: support internal mdio-bus
dt-bindings: net: dsa: qca8k: fix example
net: phy: don't clear BMCR in genphy_soft_reset
bpf, libbpf: clarify bump in libbpf version info
bpf, libbpf: fix version info and add it to shared object
rxrpc: avoid clang -Wuninitialized warning
tipc: tipc clang warning
net: sched: fix cleanup NULL pointer exception in act_mirr
r8169: fix cable re-plugging issue
net: ethernet: ti: fix possible object reference leak
net: ibm: fix possible object reference leak
...
free the symlink body after the same RCU delay we have for freeing the
struct inode itself, so that traversal during RCU pathwalk wouldn't step
into freed memory.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
VirtualBox 6.0.x has a new feature where the guest kernel driver passes
info about the origin of the request (e.g. userspace or kernelspace) to
the hypervisor.
If we do not pass this information then when running the 6.0.x userspace
guest-additions tools on a 6.0.x host, some requests will get denied
with a VERR_VERSION_MISMATCH error, breaking vboxservice.service and
the mounting of shared folders marked to be auto-mounted.
This commit implements passing the requestor info to the host, fixing this.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Unlike 'client_ops' which is initialized to 'default_client_ops', the
port operations 'ops' may be left to NULL.
Check the 'ops' value before checking the 'ops->x' value.
Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Echo "" to /sys/module/kgdboc/parameters/kgdboc will fail with "No such
device” error.
This is caused by function "configure_kgdboc" who init err to ENODEV
when the config is empty (legal input) the code go out with ENODEV
returned.
Fixes: 2dd4531686 ("kgdboc: Fix restrict error")
Signed-off-by: Wentao Wang <witallwang@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In half-duplex operation, RX should be started after TX completes.
If DMA is used, there is a case when the DMA transfer completes but the
TX FIFO is not emptied, so the RX cannot be restarted just yet.
Use a boolean variable to store this state and rearm TX interrupt mask
to be signaled again that the transfer finished. In interrupt transmit
handler this variable is used to start RX. A warning message is generated
if RX is activated before TX fifo is cleared.
Fixes: b389f173aa ("tty/serial: atmel: RS485 half duplex w/DMA: enable
RX after TX is done")
Signed-off-by: Razvan Stefanescu <razvan.stefanescu@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use a helper function to check that a port needs to use half duplex
communication, replacing several occurrences of multi-line bit checking.
Fixes: b389f173aa ("tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Razvan Stefanescu <razvan.stefanescu@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the kernel is compiled with preemption enabled, the URB completion
handler can run in parallel with the work responsible for waking up the
tty layer. If the URB handler sets the EVENT_TTY_WAKEUP bit during the
call to tty_port_tty_wakeup() to signal that there is room for additional
input, it will be cleared at the end of this call. As a result, TX traffic
on the upper layer will be blocked.
This can be seen with a kernel configured with CONFIG_PREEMPT, and a fast
modem connected with PPP running over a USB CDC-ACM port.
Use test_and_clear_bit() instead, which ensures that each wakeup requested
by the URB completion code will trigger a call to tty_port_tty_wakeup().
Fixes: 1aba579f3c cdc-acm: handle read pipe errors
Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
