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Linux kernel
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If a callback break occurs (change notification), afs_getattr() needs to
issue an FS.FetchStatus RPC operation to update the status of the file
being examined by the stat-family of system calls.
Fix afs_getattr() to do this if AFS_VNODE_CB_PROMISED has been cleared
on a vnode by a callback break. Skip this if AT_STATX_DONT_SYNC is set.
This can be tested by appending to a file on one AFS client and then
using "stat -L" to examine its length on a machine running kafs. This
can also be watched through tracing on the kafs machine. The callback
break is seen:
kworker/1:1-46 [001] ..... 978.910812: afs_cb_call: c=0000005f YFSCB.CallBack
kworker/1:1-46 [001] ...1. 978.910829: afs_cb_break: 100058:23b4c:242d2c2 b=2 s=1 break-cb
kworker/1:1-46 [001] ..... 978.911062: afs_call_done: c=0000005f ret=0 ab=0 [0000000082994ead]
And then the stat command generated no traffic if unpatched, but with
this change a call to fetch the status can be observed:
stat-4471 [000] ..... 986.744122: afs_make_fs_call: c=000000ab 100058:023b4c:242d2c2 YFS.FetchStatus
stat-4471 [000] ..... 986.745578: afs_call_done: c=000000ab ret=0 ab=0 [0000000087fc8c84]
Fixes: 08e0e7c82eea ("[AF_RXRPC]: Make the in-kernel AFS filesystem use AF_RXRPC.")
Reported-by: Markus Suvanto <markus.suvanto@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
Tested-by: kafs-testing+fedora34_64checkkafs-build-496@auristor.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216010
Link: https://lore.kernel.org/r/165308359800.162686.14122417881564420962.stgit@warthog.procyon.org.uk/ # v1
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull i2c fixes from Wolfram Sang:
"Some I2C driver bugfixes for 5.18. Nothing spectacular but worth
fixing"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
drivers: i2c: thunderx: Allow driver to work with ACPI defined TWSI controllers
i2c: ismt: Provide a DMA buffer for Interrupt Cause Logging
i2c: mt7621: fix missing clk_disable_unprepare() on error in mtk_i2c_probe()
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix and validate CPU map inputs in synthetic PERF_RECORD_STAT events
in 'perf stat'.
- Fix x86's arch__intr_reg_mask() for the hybrid platform.
- Address 'perf bench numa' compiler error on s390.
- Fix check for btf__load_from_kernel_by_id() in libbpf.
- Fix "all PMU test" 'perf test' to skip hv_24x7/hv_gpci tests on
powerpc.
- Fix session topology test to skip the test in guest environment.
- Skip BPF 'perf test' if clang is not present.
- Avoid shell test description infinite loop in 'perf test'.
- Fix Intel LBR callstack entries and nr print message.
* tag 'perf-tools-fixes-for-v5.18-2022-05-21' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf session: Fix Intel LBR callstack entries and nr print message
perf test bpf: Skip test if clang is not present
perf test session topology: Fix test to skip the test in guest environment
perf bench numa: Address compiler error on s390
perf test: Avoid shell test description infinite loop
perf regs x86: Fix arch__intr_reg_mask() for the hybrid platform
perf test: Fix "all PMU test" to skip hv_24x7/hv_gpci tests on powerpc
perf stat: Fix and validate CPU map inputs in synthetic PERF_RECORD_STAT events
perf build: Fix check for btf__load_from_kernel_by_id() in libbpf
Due to i2c->adap.dev.fwnode not being set, ACPI_COMPANION() wasn't properly
found for TWSI controllers.
Signed-off-by: Szymon Balcerak <sbalcerak@marvell.com>
Signed-off-by: Piyush Malgujar <pmalgujar@marvell.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Pull input fixes from Dmitry Torokhov:
"A small fixup to ili210x touchscreen driver, and updated maintainer
entry for the device tree binding of Mediatek 6779 keypad:
- fix reset timing of Ilitek touchscreens
- update maintainer entry of DT binding of Mediatek 6779 keypad"
* tag 'input-for-v5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: ili210x - use one common reset implementation
Input: ili210x - fix reset timing
dt-bindings: input: mediatek,mt6779-keypad: update maintainer
When generating callstack information from branch_stack(Intel LBR), the
actual number of callstack entry should be bigger than the number of
branch_stack, for example:
branch_stack records:
B() -> C()
A() -> B()
converted callstack records should be:
C()
B()
A()
though, the number of callstack equals
to the number of branch stack plus 1.
This patch fixes above issue in branch_stack__printf(). For example,
# echo 'scale=2000; 4*a(1)' > cmd
# perf record --call-graph lbr bc -l < cmd
Before applying this patch, `perf script -D` output:
1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
... LBR call chain: nr:8
..... 0: fffffffffffffe00
..... 1: 000000000040a410
..... 2: 000000000040573c
..... 3: 0000000000408650
..... 4: 00000000004022f2
..... 5: 00000000004015f5
..... 6: 00007f5ed6dcb553
..... 7: 0000000000401698
... FP chain: nr:2
..... 0: fffffffffffffe00
..... 1: 000000000040a6d8
... branch callstack: nr:6 # which is not consistent with LBR records.
..... 0: 000000000040a410
..... 1: 0000000000408650 # ditto
..... 2: 00000000004022f2
..... 3: 00000000004015f5
..... 4: 00007f5ed6dcb553
..... 5: 0000000000401698
... thread: bc:17990
...... dso: /usr/bin/bc
bc 17990 1220022.677386: 894172 cycles:
40a410 [unknown] (/usr/bin/bc)
40573c [unknown] (/usr/bin/bc)
408650 [unknown] (/usr/bin/bc)
4022f2 [unknown] (/usr/bin/bc)
4015f5 [unknown] (/usr/bin/bc)
7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
401698 [unknown] (/usr/bin/bc)
After applied:
1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
... LBR call chain: nr:8
..... 0: fffffffffffffe00
..... 1: 000000000040a410
..... 2: 000000000040573c
..... 3: 0000000000408650
..... 4: 00000000004022f2
..... 5: 00000000004015f5
..... 6: 00007f5ed6dcb553
..... 7: 0000000000401698
... FP chain: nr:2
..... 0: fffffffffffffe00
..... 1: 000000000040a6d8
... branch callstack: nr:7
..... 0: 000000000040a410
..... 1: 000000000040573c
..... 2: 0000000000408650
..... 3: 00000000004022f2
..... 4: 00000000004015f5
..... 5: 00007f5ed6dcb553
..... 6: 0000000000401698
... thread: bc:17990
...... dso: /usr/bin/bc
bc 17990 1220022.677386: 894172 cycles:
40a410 [unknown] (/usr/bin/bc)
40573c [unknown] (/usr/bin/bc)
408650 [unknown] (/usr/bin/bc)
4022f2 [unknown] (/usr/bin/bc)
4015f5 [unknown] (/usr/bin/bc)
7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
401698 [unknown] (/usr/bin/bc)
Change from v1:
- refined code style according to Jiri's review comments.
Signed-off-by: Chengdong Li <chengdongli@tencent.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: likexu@tencent.com
Link: https://lore.kernel.org/r/20220517015726.96131-1-chengdongli@tencent.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before sending a MSI the hardware writes information pertinent to the
interrupt cause to a memory location pointed by SMTICL register. This
memory holds three double words where the least significant bit tells
whether the interrupt cause of master/target/error is valid. The driver
does not use this but we need to set it up because otherwise it will
perform DMA write to the default address (0) and this will cause an
IOMMU fault such as below:
DMAR: DRHD: handling fault status reg 2
DMAR: [DMA Write] Request device [00:12.0] PASID ffffffff fault addr 0
[fault reason 05] PTE Write access is not set
To prevent this from happening, provide a proper DMA buffer for this
that then gets mapped by the IOMMU accordingly.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Pull SCSI fixes from James Bottomley:
"Two patches, both in drivers.
The iscsi one is fixing the cpumask issue you commented on and the ufs
one is a late arriving fix for conditions that can occur in Host
Performance Booster reads"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: core: Fix referencing invalid rsp field
scsi: target: Fix incorrect use of cpumask_t
Rename ili251x_hardware_reset() to ili210x_hardware_reset(), change its
parameter from struct device * to struct gpio_desc *, and use it as one
single consistent reset implementation all over the driver. Also increase
the minimum reset duration to 12ms, to make sure the reset is really
within the spec.
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20220518210423.106555-1-marex@denx.de
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Perf BPF filter test fails in environment where "clang" is not
installed.
Test failure logs:
<<>>
42: BPF filter :
42.1: Basic BPF filtering : Skip
42.2: BPF pinning : FAILED!
42.3: BPF prologue generation : FAILED!
<<>>
Enabling verbose option provided debug logs which says clang/llvm needs
to be installed. Snippet of verbose logs:
<<>>
42.2: BPF pinning :
--- start ---
test child forked, pid 61423
ERROR: unable to find clang.
Hint: Try to install latest clang/llvm to support BPF.
Check your $PATH
<<logs_here>>
Failed to compile test case: 'Basic BPF llvm compile'
Unable to get BPF object, fix kbuild first
test child finished with -1
---- end ----
BPF filter subtest 2: FAILED!
<<>>
Here subtests, "BPF pinning" and "BPF prologue generation" failed and
logs shows clang/llvm is needed. After installing clang, testcase
passes.
Reason on why subtest failure happens though logs has proper debug
information:
Main function __test__bpf calls test_llvm__fetch_bpf_obj by
passing 4th argument as true ( 4th arguments maps to parameter
"force" in test_llvm__fetch_bpf_obj ). But this will cause
test_llvm__fetch_bpf_obj to skip the check for clang/llvm.
Snippet of code part which checks for clang based on
parameter "force" in test_llvm__fetch_bpf_obj:
<<>>
if (!force && (!llvm_param.user_set_param &&
<<>>
Since force is set to "false", test won't get skipped and fails to
compile test case. The BPF code compilation needs clang, So pass the
fourth argument as "false" and also skip the test if reason for return
is "TEST_SKIP"
After the patch:
<<>>
42: BPF filter :
42.1: Basic BPF filtering : Skip
42.2: BPF pinning : Skip
42.3: BPF prologue generation : Skip
<<>>
Fixes: ba1fae431e74bb42 ("perf test: Add 'perf test BPF'")
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nageswara R Sastry <rnsastry@linux.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lore.kernel.org/r/20220511115438.84032-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix the missing clk_disable_unprepare() before return
from mtk_i2c_probe() in the error handling case.
Fixes: d04913ec5f89 ("i2c: mt7621: Add MediaTek MT7621/7628/7688 I2C driver")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Correctly expose GICv3 support even if no irqchip is created so
that userspace doesn't observe it changing pointlessly (fixing a
regression with QEMU)
- Don't issue a hypercall to set the id-mapped vectors when protected
mode is enabled (fix for pKVM in combination with CPUs affected by
Spectre-v3a)
x86 (five oneliners, of which the most interesting two are):
- a NULL pointer dereference on INVPCID executed with paging
disabled, but only if KVM is using shadow paging
- an incorrect bsearch comparison function which could truncate the
result and apply PMU event filtering incorrectly. This one comes
with a selftests update too"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86/mmu: fix NULL pointer dereference on guest INVPCID
KVM: x86: hyper-v: fix type of valid_bank_mask
KVM: Free new dirty bitmap if creating a new memslot fails
KVM: eventfd: Fix false positive RCU usage warning
selftests: kvm/x86: Verify the pmu event filter matches the correct event
selftests: kvm/x86: Add the helper function create_pmu_event_filter
kvm: x86/pmu: Fix the compare function used by the pmu event filter
KVM: arm64: Don't hypercall before EL2 init
KVM: arm64: vgic-v3: Consistently populate ID_AA64PFR0_EL1.GIC
KVM: x86/mmu: Update number of zapped pages even if page list is stable
Fix referencing sense data when it is invalid. When the length of the data
segment is 0, there is no valid information in the rsp field, so
ufshpb_rsp_upiu() is returned without additional operation.
Link: https://lore.kernel.org/r/252651381.41652940482659.JavaMail.epsvc@epcpadp4
Fixes: 4b5f49079c52 ("scsi: ufs: ufshpb: L2P map management for HPB read")
Acked-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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