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2022-03-20Linux 5.17v5.17Linus Torvalds1-1/+1
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-20kvm/emulate: Fix SETcc emulation function offsets with SLSBorislav Petkov1-2/+17
The commit in Fixes started adding INT3 after RETs as a mitigation against straight-line speculation. The fastop SETcc implementation in kvm's insn emulator uses macro magic to generate all possible SETcc functions and to jump to them when emulating the respective instruction. However, it hardcodes the size and alignment of those functions to 4: a three-byte SETcc insn and a single-byte RET. BUT, with SLS, there's an INT3 that gets slapped after the RET, which brings the whole scheme out of alignment: 15: 0f 90 c0 seto %al 18: c3 ret 19: cc int3 1a: 0f 1f 00 nopl (%rax) 1d: 0f 91 c0 setno %al 20: c3 ret 21: cc int3 22: 0f 1f 00 nopl (%rax) 25: 0f 92 c0 setb %al 28: c3 ret 29: cc int3 and this explodes like this: int3: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 2435 Comm: qemu-system-x86 Not tainted 5.17.0-rc8-sls #1 Hardware name: Dell Inc. Precision WorkStation T3400 /0TP412, BIOS A14 04/30/2012 RIP: 0010:setc+0x5/0x8 [kvm] Code: 00 00 0f 1f 00 0f b6 05 43 24 06 00 c3 cc 0f 1f 80 00 00 00 00 0f 90 c0 c3 cc 0f \ 1f 00 0f 91 c0 c3 cc 0f 1f 00 0f 92 c0 c3 cc <0f> 1f 00 0f 93 c0 c3 cc 0f 1f 00 \ 0f 94 c0 c3 cc 0f 1f 00 0f 95 c0 Call Trace: <TASK> ? x86_emulate_insn [kvm] ? x86_emulate_instruction [kvm] ? vmx_handle_exit [kvm_intel] ? kvm_arch_vcpu_ioctl_run [kvm] ? kvm_vcpu_ioctl [kvm] ? __x64_sys_ioctl ? do_syscall_64 ? entry_SYSCALL_64_after_hwframe </TASK> Raise the alignment value when SLS is enabled and use a macro for that instead of hard-coding naked numbers. Fixes: e463a09af2f0 ("x86: Add straight-line-speculation mitigation") Reported-by: Jamie Heilman <jamie@audible.transient.net> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Jamie Heilman <jamie@audible.transient.net> Link: https://lore.kernel.org/r/YjGzJwjrvxg5YZ0Z@audible.transient.net [Add a comment and a bit of safety checking, since this is going to be changed again for IBT support. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-18parisc: Avoid flushing cache on cache-less machinesHelge Deller1-0/+4
Avoid flushing caches in __flush_cache_page() and __purge_cache_page() if the machine hasn't data or instruction caches - as e.g. in qemu. Signed-off-by: Helge Deller <deller@gmx.de>
2022-03-18perf parse-events: Ignore case in topdown.slots checkIan Rogers1-1/+1
An issue with icelakex metrics: https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/tree/tools/perf/pmu-events/arch/x86/icelakex/icx-metrics.json?h=perf/core&id=65eab2bc7dab326ee892ec5a4c749470b368b51a#n48 That causes the slots not to be first. Fixes: 94dbfd6781a0e87b ("perf parse-events: Architecture specific leader override") Reported-by: Caleb Biggers <caleb.biggers@intel.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.garry@huawei.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Zhengjun Xing <zhengjun.xing@linux.intel.com> Link: https://lore.kernel.org/r/20220317224309.543736-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-03-18perf evlist: Avoid iteration for empty evlist.Ian Rogers1-11/+17
As seen with 'perf stat --null ..' and reported in: https://lore.kernel.org/lkml/YjCLcpcX2peeQVCH@kernel.org/ v2. Avoids setting evsel in the empty list case as suggested by Jiri Olsa. Committer testing: Before: $ perf stat --null sleep 1 Segmentation fault (core dumped) $ After: $ perf stat --null sleep 1 Performance counter stats for 'sleep 1': 1.010340646 seconds time elapsed 0.001420000 seconds user 0.000000000 seconds sys $ Fixes: 472832d2c000b961 ("perf evlist: Refactor evlist__for_each_cpu()") Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20220317231643.550902-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-03-18perf symbols: Fix symbol size calculation conditionMichael Petlan1-1/+1
Before this patch, the symbol end address fixup to be called, needed two conditions being met: if (prev->end == prev->start && prev->end != curr->start) Where "prev->end == prev->start" means that prev is zero-long (and thus needs a fixup) and "prev->end != curr->start" means that fixup hasn't been applied yet However, this logic is incorrect in the following situation: *curr = {rb_node = {__rb_parent_color = 278218928, rb_right = 0x0, rb_left = 0x0}, start = 0xc000000000062354, end = 0xc000000000062354, namelen = 40, type = 2 '\002', binding = 0 '\000', idle = 0 '\000', ignore = 0 '\000', inlined = 0 '\000', arch_sym = 0 '\000', annotate2 = false, name = 0x1159739e "kprobe_optinsn_page\t[__builtin__kprobes]"} *prev = {rb_node = {__rb_parent_color = 278219041, rb_right = 0x109548b0, rb_left = 0x109547c0}, start = 0xc000000000062354, end = 0xc000000000062354, namelen = 12, type = 2 '\002', binding = 1 '\001', idle = 0 '\000', ignore = 0 '\000', inlined = 0 '\000', arch_sym = 0 '\000', annotate2 = false, name = 0x1095486e "optinsn_slot"} In this case, prev->start == prev->end == curr->start == curr->end, thus the condition above thinks that "we need a fixup due to zero length of prev symbol, but it has been probably done, since the prev->end == curr->start", which is wrong. After the patch, the execution path proceeds to arch__symbols__fixup_end function which fixes up the size of prev symbol by adding page_size to its end offset. Fixes: 3b01a413c196c910 ("perf symbols: Improve kallsyms symbol end addr calculation") Signed-off-by: Michael Petlan <mpetlan@redhat.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Link: http://lore.kernel.org/lkml/20220317135536.805-1-mpetlan@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-03-18io_uring: terminate manual loop iterator loop correctly for non-vecsJens Axboe1-2/+4
The fix for not advancing the iterator if we're using fixed buffers is broken in that it can hit a condition where we don't terminate the loop. This results in io-wq looping forever, asking to read (or write) 0 bytes for every subsequent loop. Reported-by: Joel Jaeschke <joel.jaeschke@gmail.com> Link: https://github.com/axboe/liburing/issues/549 Fixes: 16c8d2df7ec0 ("io_uring: ensure symmetry in handling iter types in loop_rw_iter()") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18io_uring: don't check unrelated req->open.how in accept requestJens Axboe1-2/+1
Looks like a victim of too much copy/paste, we should not be looking at req->open.how in accept. The point is to check CLOEXEC and error out, which we don't invalid direct descriptors on exec. Hence any attempt to get a direct descriptor with CLOEXEC is invalid. No harm is done here, as req->open.how.flags overlaps with req->accept.flags, but it's very confusing and might change if either of those command structs are modified. Fixes: aaa4db12ef7b ("io_uring: accept directly into fixed file table") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18block: cancel all throttled bios in del_gendisk()Yu Kuai3-1/+41
Throttled bios can't be issued after del_gendisk() is done, thus it's better to cancel them immediately rather than waiting for throttle is done. For example, if user thread is throttled with low bps while it's issuing large io, and the device is deleted. The user thread will wait for a long time for io to return. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220318130144.1066064-4-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18block: let blkcg_gq grab request queue's refcntMing Lei1-0/+5
In the whole lifetime of blkcg_gq instance, ->q will be referred, such as, ->pd_free_fn() is called in blkg_free, and throtl_pd_free() still may touch the request queue via &tg->service_queue.pending_timer which is handled by throtl_pending_timer_fn(), so it is reasonable to grab request queue's refcnt by blkcg_gq instance. Previously blkcg_exit_queue() is called from blk_release_queue, and it is hard to avoid the use-after-free. But recently commit 1059699f87eb ("block: move blkcg initialization/destroy into disk allocation/release handler") is merged to for-5.18/block, it becomes simple to fix the issue by simply grabbing request queue's refcnt. Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220318130144.1066064-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18block: avoid use-after-free on throttle dataMing Lei1-1/+11
In throtl_pending_timer_fn(), request queue is retrieved from throttle data. And tg's pending timer is deleted synchronously when releasing the associated blkg, at that time, throttle data may have been freed since commit 1059699f87eb ("block: move blkcg initialization/destroy into disk allocation/release handler") moves freeing q->td to disk_release() from blk_release_queue(). So use-after-free on q->td in throtl_pending_timer_fn can be triggered. Fixes the issue by: - do nothing in case that disk is released, when there isn't any bio to dispatch - retrieve request queue from blkg instead of throttle data for non top-level pending timer. Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220318130144.1066064-2-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18arm64: errata: avoid duplicate field initializerArnd Bergmann1-1/+0
The '.type' field is initialized both in place and in the macro as reported by this W=1 warning: arch/arm64/include/asm/cpufeature.h:281:9: error: initialized field overwritten [-Werror=override-init] 281 | (ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU) | ^ arch/arm64/kernel/cpu_errata.c:136:17: note: in expansion of macro 'ARM64_CPUCAP_LOCAL_CPU_ERRATUM' 136 | .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/arm64/kernel/cpu_errata.c:145:9: note: in expansion of macro 'ERRATA_MIDR_RANGE' 145 | ERRATA_MIDR_RANGE(m, var, r_min, var, r_max) | ^~~~~~~~~~~~~~~~~ arch/arm64/kernel/cpu_errata.c:613:17: note: in expansion of macro 'ERRATA_MIDR_REV_RANGE' 613 | ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2), | ^~~~~~~~~~~~~~~~~~~~~ arch/arm64/include/asm/cpufeature.h:281:9: note: (near initialization for 'arm64_errata[18].type') 281 | (ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU) | ^ Remove the extranous initializer. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 1dd498e5e26a ("KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata") Link: https://lore.kernel.org/r/20220316183800.1546731-1-arnd@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-03-18clocksource: acpi_pm: fix return value of __setup handlerRandy Dunlap1-2/+4
__setup() handlers should return 1 to obsolete_checksetup() in init/main.c to indicate that the boot option has been handled. A return of 0 causes the boot option/value to be listed as an Unknown kernel parameter and added to init's (limited) environment strings. The __setup() handler interface isn't meant to handle negative return values -- they are non-zero, so they mean "handled" (like a return value of 1 does), but that's just a quirk. So return 1 from parse_pmtmr(). Also print a warning message if kstrtouint() returns an error. Fixes: 6b148507d3d0 ("pmtmr: allow command line override of ioport") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-18arm64: fix clang warning about TRAMP_VALIASArnd Bergmann1-2/+2
The newly introduced TRAMP_VALIAS definition causes a build warning with clang-14: arch/arm64/include/asm/vectors.h:66:31: error: arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension [-Werror,-Wnull-pointer-arithmetic] return (char *)TRAMP_VALIAS + SZ_2K * slot; Change the addition to something clang does not complain about. Fixes: bd09128d16fa ("arm64: Add percpu vectors for EL1") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: James Morse <james.morse@arm.com> Link: https://lore.kernel.org/r/20220316183833.1563139-1-arnd@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-03-18parisc: Avoid using hardware single-step in kprobesHelge Deller3-19/+24
This patch changes the kprobe and kretprobe feature to use another break instruction instead of relying on the hardware single-step feature. That way those kprobes now work in qemu as well, because in qemu we don't emulate yet single-stepping. Signed-off-by: Helge Deller <deller@gmx.de>
2022-03-18block: limit request dispatch loop durationShin'ichiro Kawasaki1-1/+8
When IO requests are made continuously and the target block device handles requests faster than request arrival, the request dispatch loop keeps on repeating to dispatch the arriving requests very long time, more than a minute. Since the loop runs as a workqueue worker task, the very long loop duration triggers workqueue watchdog timeout and BUG [1]. To avoid the very long loop duration, break the loop periodically. When opportunity to dispatch requests still exists, check need_resched(). If need_resched() returns true, the dispatch loop already consumed its time slice, then reschedule the dispatch work and break the loop. With heavy IO load, need_resched() does not return true for 20~30 seconds. To cover such case, check time spent in the dispatch loop with jiffies. If more than 1 second is spent, reschedule the dispatch work and break the loop. [1] [ 609.691437] BUG: workqueue lockup - pool cpus=10 node=1 flags=0x0 nice=-20 stuck for 35s! [ 609.701820] Showing busy workqueues and worker pools: [ 609.707915] workqueue events: flags=0x0 [ 609.712615] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 [ 609.712626] pending: drm_fb_helper_damage_work [drm_kms_helper] [ 609.712687] workqueue events_freezable: flags=0x4 [ 609.732943] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 [ 609.732952] pending: pci_pme_list_scan [ 609.732968] workqueue events_power_efficient: flags=0x80 [ 609.751947] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 [ 609.751955] pending: neigh_managed_work [ 609.752018] workqueue kblockd: flags=0x18 [ 609.769480] pwq 21: cpus=10 node=1 flags=0x0 nice=-20 active=3/256 refcnt=4 [ 609.769488] in-flight: 1020:blk_mq_run_work_fn [ 609.769498] pending: blk_mq_timeout_work, blk_mq_run_work_fn [ 609.769744] pool 21: cpus=10 node=1 flags=0x0 nice=-20 hung=35s workers=2 idle: 67 [ 639.899730] BUG: workqueue lockup - pool cpus=10 node=1 flags=0x0 nice=-20 stuck for 66s! [ 639.909513] Showing busy workqueues and worker pools: [ 639.915404] workqueue events: flags=0x0 [ 639.920197] pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 [ 639.920215] pending: drm_fb_helper_damage_work [drm_kms_helper] [ 639.920365] workqueue kblockd: flags=0x18 [ 639.939932] pwq 21: cpus=10 node=1 flags=0x0 nice=-20 active=3/256 refcnt=4 [ 639.939942] in-flight: 1020:blk_mq_run_work_fn [ 639.939955] pending: blk_mq_timeout_work, blk_mq_run_work_fn [ 639.940212] pool 21: cpus=10 node=1 flags=0x0 nice=-20 hung=66s workers=2 idle: 67 Fixes: 6e6fcbc27e778 ("blk-mq: support batching dispatch in case of io") Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Cc: stable@vger.kernel.org # v5.10+ Link: https://lore.kernel.org/linux-block/20220310091649.zypaem5lkyfadymg@shindev/ Link: https://lore.kernel.org/r/20220318022641.133484-1-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18io_uring: manage provided buffers strictly orderedJens Axboe1-62/+92
Workloads using provided buffers benefit from using and returning buffers in the right order, and so does TLBs for that matter. Manage the internal buffer list in a straight list, rather than use the head buffer as the insertion node. Use a hashed list for the buffer group IDs instead of xarray, the overhead is much lower this way. xarray provides internal locking and other trickery that is handy for some uses cases, but io_uring already locks internally for the buffer manipulation and needs none of that. This is good for about a 2% reduction in overhead, combination of the improved management and the fact that the workload has an easier time bundling back provided buffers. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17parisc: Improve CPU socket and core bootup info textHelge Deller1-2/+2
Improve CPU bootup info text from: CPU1: thread -1, cpu 0, socket 1 to CPU1: cpu core 0 of socket 1 Signed-off-by: Helge Deller <deller@gmx.de>
2022-03-17parisc: Enable ARCH_HAS_DEBUG_VM_PGTABLEHelge Deller1-0/+1
Allow to enable page table boot-up checks. Suggested-by: Rolf Eike Beer <eike-kernel@sf-tec.de> Signed-off-by: Helge Deller <deller@gmx.de>
2022-03-17selftests: vm: fix clang build error multiple output filesYosry Ahmed1-4/+2
When building the vm selftests using clang, some errors are seen due to having headers in the compilation command: clang -Wall -I ../../../../usr/include -no-pie gup_test.c ../../../../mm/gup_test.h -lrt -lpthread -o .../tools/testing/selftests/vm/gup_test clang: error: cannot specify -o when generating multiple output files make[1]: *** [../lib.mk:146: .../tools/testing/selftests/vm/gup_test] Error 1 Rework to add the header files to LOCAL_HDRS before including ../lib.mk, since the dependency is evaluated in '$(OUTPUT)/%:%.c $(LOCAL_HDRS)' in file lib.mk. Link: https://lkml.kernel.org/r/20220304000645.1888133-1-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-17ocfs2: fix crash when initialize filecheck kobj failsJoseph Qi1-11/+11
Once s_root is set, genric_shutdown_super() will be called if fill_super() fails. That means, we will call ocfs2_dismount_volume() twice in such case, which can lead to kernel crash. Fix this issue by initializing filecheck kobj before setting s_root. Link: https://lkml.kernel.org/r/20220310081930.86305-1-joseph.qi@linux.alibaba.com Fixes: 5f483c4abb50 ("ocfs2: add kobject for online file check") Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-17configs/debug: restore DEBUG_INFO=y for overridingQian Cai1-0/+1
Previously, I failed to realize that Kees' patch [1] has not been merged into the mainline yet, and dropped DEBUG_INFO=y too eagerly from the mainline. As the results, "make debug.config" won't be able to flip DEBUG_INFO=n from the existing .config. This should close the gaps of a few weeks before Kees' patch is there, and work regardless of their merging status anyway. Link: https://lore.kernel.org/all/20220125075126.891825-1-keescook@chromium.org/ [1] Link: https://lkml.kernel.org/r/20220308153524.8618-1-quic_qiancai@quicinc.com Signed-off-by: Qian Cai <quic_qiancai@quicinc.com> Reported-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-17mm: swap: get rid of livelock in swapin readaheadGuo Ziliang1-1/+1
In our testing, a livelock task was found. Through sysrq printing, same stack was found every time, as follows: __swap_duplicate+0x58/0x1a0 swapcache_prepare+0x24/0x30 __read_swap_cache_async+0xac/0x220 read_swap_cache_async+0x58/0xa0 swapin_readahead+0x24c/0x628 do_swap_page+0x374/0x8a0 __handle_mm_fault+0x598/0xd60 handle_mm_fault+0x114/0x200 do_page_fault+0x148/0x4d0 do_translation_fault+0xb0/0xd4 do_mem_abort+0x50/0xb0 The reason for the livelock is that swapcache_prepare() always returns EEXIST, indicating that SWAP_HAS_CACHE has not been cleared, so that it cannot jump out of the loop. We suspect that the task that clears the SWAP_HAS_CACHE flag never gets a chance to run. We try to lower the priority of the task stuck in a livelock so that the task that clears the SWAP_HAS_CACHE flag will run. The results show that the system returns to normal after the priority is lowered. In our testing, multiple real-time tasks are bound to the same core, and the task in the livelock is the highest priority task of the core, so the livelocked task cannot be preempted. Although cond_resched() is used by __read_swap_cache_async, it is an empty function in the preemptive system and cannot achieve the purpose of releasing the CPU. A high-priority task cannot release the CPU unless preempted by a higher-priority task. But when this task is already the highest priority task on this core, other tasks will not be able to be scheduled. So we think we should replace cond_resched() with schedule_timeout_uninterruptible(1), schedule_timeout_interruptible will call set_current_state first to set the task state, so the task will be removed from the running queue, so as to achieve the purpose of giving up the CPU and prevent it from running in kernel mode for too long. (akpm: ugly hack becomes uglier. But it fixes the issue in a backportable-to-stable fashion while we hopefully work on something better) Link: https://lkml.kernel.org/r/20220221111749.1928222-1-cgel.zte@gmail.com Signed-off-by: Guo Ziliang <guo.ziliang@zte.com.cn> Reported-by: Zeal Robot <zealci@zte.com.cn> Reviewed-by: Ran Xiaokai <ran.xiaokai@zte.com.cn> Reviewed-by: Jiang Xuexin <jiang.xuexin@zte.com.cn> Reviewed-by: Yang Yang <yang.yang29@zte.com.cn> Acked-by: Hugh Dickins <hughd@google.com> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roger Quadros <rogerq@kernel.org> Cc: Ziliang Guo <guo.ziliang@zte.com.cn> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-17iavf: Fix hang during reboot/shutdownIvan Vecera1-0/+7
Recent commit 974578017fc1 ("iavf: Add waiting so the port is initialized in remove") adds a wait-loop at the beginning of iavf_remove() to ensure that port initialization is finished prior unregistering net device. This causes a regression in reboot/shutdown scenario because in this case callback iavf_shutdown() is called and this callback detaches the device, makes it down if it is running and sets its state to __IAVF_REMOVE. Later shutdown callback of associated PF driver (e.g. ice_shutdown) is called. That callback calls among other things sriov_disable() that calls indirectly iavf_remove() (see stack trace below). As the adapter state is already __IAVF_REMOVE then the mentioned loop is end-less and shutdown process hangs. The patch fixes this by checking adapter's state at the beginning of iavf_remove() and skips the rest of the function if the adapter is already in remove state (shutdown is in progress). Reproducer: 1. Create VF on PF driven by ice or i40e driver 2. Ensure that the VF is bound to iavf driver 3. Reboot [52625.981294] sysrq: SysRq : Show Blocked State [52625.988377] task:reboot state:D stack: 0 pid:17359 ppid: 1 f2 [52625.996732] Call Trace: [52625.999187] __schedule+0x2d1/0x830 [52626.007400] schedule+0x35/0xa0 [52626.010545] schedule_hrtimeout_range_clock+0x83/0x100 [52626.020046] usleep_range+0x5b/0x80 [52626.023540] iavf_remove+0x63/0x5b0 [iavf] [52626.027645] pci_device_remove+0x3b/0xc0 [52626.031572] device_release_driver_internal+0x103/0x1f0 [52626.036805] pci_stop_bus_device+0x72/0xa0 [52626.040904] pci_stop_and_remove_bus_device+0xe/0x20 [52626.045870] pci_iov_remove_virtfn+0xba/0x120 [52626.050232] sriov_disable+0x2f/0xe0 [52626.053813] ice_free_vfs+0x7c/0x340 [ice] [52626.057946] ice_remove+0x220/0x240 [ice] [52626.061967] ice_shutdown+0x16/0x50 [ice] [52626.065987] pci_device_shutdown+0x34/0x60 [52626.070086] device_shutdown+0x165/0x1c5 [52626.074011] kernel_restart+0xe/0x30 [52626.077593] __do_sys_reboot+0x1d2/0x210 [52626.093815] do_syscall_64+0x5b/0x1a0 [52626.097483] entry_SYSCALL_64_after_hwframe+0x65/0xca Fixes: 974578017fc1 ("iavf: Add waiting so the port is initialized in remove") Signed-off-by: Ivan Vecera <ivecera@redhat.com> Link: https://lore.kernel.org/r/20220317104524.2802848-1-ivecera@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17net: mscc: ocelot: fix backwards compatibility with single-chain tc-flower ↵Vladimir Oltean1-1/+15
offload ACL rules can be offloaded to VCAP IS2 either through chain 0, or, since the blamed commit, through a chain index whose number encodes a specific PAG (Policy Action Group) and lookup number. The chain number is translated through ocelot_chain_to_pag() into a PAG, and through ocelot_chain_to_lookup() into a lookup number. The problem with the blamed commit is that the above 2 functions don't have special treatment for chain 0. So ocelot_chain_to_pag(0) returns filter->pag = 224, which is in fact -32, but the "pag" field is an u8. So we end up programming the hardware with VCAP IS2 entries having a PAG of 224. But the way in which the PAG works is that it defines a subset of VCAP IS2 filters which should match on a packet. The default PAG is 0, and previous VCAP IS1 rules (which we offload using 'goto') can modify it. So basically, we are installing filters with a PAG on which no packet will ever match. This is the hardware equivalent of adding filters to a chain which has no 'goto' to it. Restore the previous functionality by making ACL filters offloaded to chain 0 go to PAG 0 and lookup number 0. The choice of PAG is clearly correct, but the choice of lookup number isn't "as before" (which was to leave the lookup a "don't care"). However, lookup 0 should be fine, since even though there are ACL actions (policers) which have a requirement to be used in a specific lookup, that lookup is 0. Fixes: 226e9cd82a96 ("net: mscc: ocelot: only install TCAM entries into a specific lookup and PAG") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://lore.kernel.org/r/20220316192117.2568261-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17net: bcmgenet: skip invalid partial checksumsDoug Berger1-2/+4
The RXCHK block will return a partial checksum of 0 if it encounters a problem while receiving a packet. Since a 1's complement sum can only produce this result if no bits are set in the received data stream it is fair to treat it as an invalid partial checksum and not pass it up the stack. Fixes: 810155397890 ("net: bcmgenet: use CHECKSUM_COMPLETE for NETIF_F_RXCSUM") Signed-off-by: Doug Berger <opendmb@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20220317012812.1313196-1-opendmb@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17bnx2x: fix built-in kernel driver load failureManish Chopra3-26/+19
Commit b7a49f73059f ("bnx2x: Utilize firmware 7.13.21.0") added request_firmware() logic in probe() which caused load failure when firmware file is not present in initrd (below), as access to firmware file is not feasible during probe. Direct firmware load for bnx2x/bnx2x-e2-7.13.15.0.fw failed with error -2 Direct firmware load for bnx2x/bnx2x-e2-7.13.21.0.fw failed with error -2 This patch fixes this issue by - 1. Removing request_firmware() logic from the probe() such that .ndo_open() handle it as it used to handle it earlier 2. Given request_firmware() is removed from probe(), so driver has to relax FW version comparisons a bit against the already loaded FW version (by some other PFs of same adapter) to allow different compatible/close enough FWs with which multiple PFs may run with (in different environments), as the given PF who is in probe flow has no idea now with which firmware file version it is going to initialize the device in ndo_open() Link: https://lore.kernel.org/all/46f2d9d9-ae7f-b332-ddeb-b59802be2bab@molgen.mpg.de/ Reported-by: Paul Menzel <pmenzel@molgen.mpg.de> Tested-by: Paul Menzel <pmenzel@molgen.mpg.de> Fixes: b7a49f73059f ("bnx2x: Utilize firmware 7.13.21.0") Signed-off-by: Manish Chopra <manishc@marvell.com> Signed-off-by: Ariel Elior <aelior@marvell.com> Link: https://lore.kernel.org/r/20220316214613.6884-1-manishc@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17net: phy: mscc: Add MODULE_FIRMWARE macrosJuerg Haefliger1-0/+3
The driver requires firmware so define MODULE_FIRMWARE so that modinfo provides the details. Fixes: fa164e40c53b ("net: phy: mscc: split the driver into separate files") Signed-off-by: Juerg Haefliger <juergh@canonical.com> Link: https://lore.kernel.org/r/20220316151835.88765-1-juergh@canonical.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17cpufreq: powernow-k8: Re-order the init checksMario Limonciello1-3/+3
The powernow-k8 driver will do checks at startup that the current active driver is acpi-cpufreq and show a warning when they're not expected. Because of this the following warning comes up on systems that support amd-pstate and compiled in both drivers: `WTF driver: amd-pstate` The systems that support powernow-k8 will not support amd-pstate, so re-order the checks to validate the CPU model number first to avoid this warning being displayed on modern SOCs. Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-17ACPI: bus: Avoid using CPPC if not supported by firmwareRafael J. Wysocki3-0/+12
If the platform firmware indicates that it does not support CPPC by clearing the OSC_SB_CPC_SUPPORT and OSC_SB_CPCV2_SUPPORT bits in the platform _OSC capabilities mask, avoid attempting to evaluate _CPC which may fail in that case. Because the OSC_SB_CPC_SUPPORT and OSC_SB_CPCV2_SUPPORT bits are only added to the supported platform capabilities mask on x86, when X86_FEATURE_HWP is supported, allow _CPC to be evaluated regardless in the other cases. Link: https://lore.kernel.org/linux-acpi/CAJZ5v0i=ecAksq0TV+iLVObm-=fUfdqPABzzkgm9K6KxO1ZCcg@mail.gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2022-03-17Revert "ACPI: Pass the same capabilities to the _OSC regardless of the query ↵Rafael J. Wysocki1-8/+19
flag" Revert commit 159d8c274fd9 ("ACPI: Pass the same capabilities to the _OSC regardless of the query flag") which caused legitimate usage scenarios (when the platform firmware does not want the OS to control certain platform features controlled by the system bus scope _OSC) to break and was misguided by some misleading language in the _OSC definition in the ACPI specification (in particular, Section 6.2.11.1.3 "Sequence of _OSC Calls" that contradicts other perts of the _OSC definition). Link: https://lore.kernel.org/linux-acpi/CAJZ5v0iStA0JmO0H3z+VgQsVuQONVjKPpw0F5HKfiq=Gb6B5yw@mail.gmail.com Reported-by: Mario Limonciello <Mario.Limonciello@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2022-03-17cpuidle: intel_idle: Drop redundant backslash at line endRafael J. Wysocki1-1/+1
Drop a redundant backslash character at the end of a line in the spr_cstates[] definition. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2022-03-17cpuidle: intel_idle: Update intel_idle() kerneldoc commentRafael J. Wysocki1-3/+0
Commit bf9282dc26e7 ("cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic") moved the leave_mm() call away from intel_idle(), but it didn't update its kerneldoc comment accordingly, so do that now. Fixes: bf9282dc26e7 ("cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-17ACPI: video: Force backlight native for Clevo NL5xRU and NL5xNUWerner Sembach1-0/+75
Clevo NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2 have both a working native and video interface. However the default detection mechanism first registers the video interface before unregistering it again and switching to the native interface during boot. This results in a dangling SBIOS request for backlight change for some reason, causing the backlight to switch to ~2% once per boot on the first power cord connect or disconnect event. Setting the native interface explicitly circumvents this buggy behaviour by avoiding the unregistering process. Signed-off-by: Werner Sembach <wse@tuxedocomputers.com> Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-17net: dsa: Add missing of_node_put() in dsa_port_parse_ofMiaoqian Lin1-0/+1
The device_node pointer is returned by of_parse_phandle() with refcount incremented. We should use of_node_put() on it when done. Fixes: 6d4e5c570c2d ("net: dsa: get port type at parse time") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> Link: https://lore.kernel.org/r/20220316082602.10785-1-linmq006@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-03-17drm: Don't make DRM_PANEL_BRIDGE dependent on DRM_KMS_HELPERSThomas Zimmermann2-1/+2
Fix a number of undefined references to drm_kms_helper.ko in drm_dp_helper.ko: arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_mst_duplicate_state': drm_dp_mst_topology.c:(.text+0x2df0): undefined reference to `__drm_atomic_helper_private_obj_duplicate_state' arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_delayed_destroy_work': drm_dp_mst_topology.c:(.text+0x370c): undefined reference to `drm_kms_helper_hotplug_event' arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_mst_up_req_work': drm_dp_mst_topology.c:(.text+0x7938): undefined reference to `drm_kms_helper_hotplug_event' arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_mst_link_probe_work': drm_dp_mst_topology.c:(.text+0x82e0): undefined reference to `drm_kms_helper_hotplug_event' This happens if panel-edp.ko has been configured with DRM_PANEL_EDP=y DRM_DP_HELPER=y DRM_KMS_HELPER=m which builds DP helpers into the kernel and KMS helpers sa a module. Making DRM_PANEL_EDP select DRM_KMS_HELPER resolves this problem. To avoid a resulting cyclic dependency with DRM_PANEL_BRIDGE, don't make the latter depend on DRM_KMS_HELPER and fix the one DRM bridge drivers that doesn't already select DRM_KMS_HELPER. As KMS helpers cannot be selected directly by the user, config symbols should avoid depending on it anyway. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Fixes: 3755d35ee1d2 ("drm/panel: Select DRM_DP_HELPER for DRM_PANEL_EDP") Acked-by: Sam Ravnborg <sam@ravnborg.org> Tested-by: Brian Masney <bmasney@redhat.com> Reported-by: kernel test robot <lkp@intel.com> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Naresh Kamboju <naresh.kamboju@linaro.org> Cc: Linux Kernel Functional Testing <lkft@linaro.org> Cc: Lyude Paul <lyude@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: dri-devel@lists.freedesktop.org Cc: Dave Airlie <airlied@redhat.com> Cc: Thierry Reding <thierry.reding@gmail.com> Link: https://patchwork.freedesktop.org/patch/478296/
2022-03-17smb3: fix incorrect session setup check for multiuser mountsSteve French1-1/+2
A recent change to how the SMB3 server (socket) and session status is managed regressed multiuser mounts by changing the check for whether session setup is needed to the socket (TCP_Server_info) structure instead of the session struct (cifs_ses). Add additional check in cifs_setup_sesion to fix this. Fixes: 73f9bfbe3d81 ("cifs: maintain a state machine for tcp/smb/tcon sessions") Reported-by: Ronnie Sahlberg <lsahlber@redhat.com> Acked-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-17net: handle ARPHRD_PIMREG in dev_is_mac_header_xmit()Nicolas Dichtel1-0/+1
This kind of interface doesn't have a mac header. This patch fixes bpf_redirect() to a PIM interface. Fixes: 27b29f63058d ("bpf: add bpf_redirect() helper") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Link: https://lore.kernel.org/r/20220315092008.31423-1-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-17io_uring: fold evfd signalling under a slower pathPavel Begunkov1-26/+34
Add ->has_evfd flag, which is true IFF there is an eventfd attached, and use it to hide io_eventfd_signal() into __io_commit_cqring_flush() and combine fast checks in a single if. Also, gcc 11.2 wasn't inlining io_cqring_ev_posted() without this change, so helps with that as well. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/f6168471997decded475a063f92915787975a30b.1647481208.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17io_uring: thin down io_commit_cqring()Pavel Begunkov1-8/+15
io_commit_cqring() is currently always under spinlock section, so it's always better to keep it as slim as possible. Move __io_commit_cqring_flush() out of it into ev_posted*(). If fast checks do fail and this post-processing is required, we'll reacquire ->completion_lock, which is fine as we don't care about performance of draining and offset timeouts. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/ec4e81fd720d3bc7bca8cb9152e080dad1a052f1.1647481208.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17io_uring: shuffle io_eventfd_signal() bits aroundPavel Begunkov1-8/+5
A preparation patch, which moves a fast ->io_ev_fd check out of io_eventfd_signal() into ev_posted*(). Compilers are smart enough for it to not change anything, but will need it later. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/ec4091ac76d43912b73917e8db651c2dac4b7b01.1647481208.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17io_uring: remove extra barrier for non-sqpoll iopollPavel Begunkov1-4/+1
smp_mb() in io_cqring_ev_posted_iopoll() is only there because of waitqueue_active(). However, non-SQPOLL IOPOLL ring doesn't wake the CQ and so the barrier there is useless. Kill it, it's usually pretty expensive. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/d72e8ef6f7a3f6a72e18fad8409f7d47afc8da7d.1647481208.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17io_uring: fix provided buffer return on failure for kiocb_done()Pavel Begunkov1-7/+3
Use io_req_complete_failed() in kiocb_done(). This cleans up the code, but also ensures that a provided buffers is correctly freed on failure. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/a4880106fcf199d5810707fe2d17126fcdf18bc4.1647481208.git.asml.silence@gmail.com [axboe: split from previous patch] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17io_uring: extend provided buf return to failsPavel Begunkov1-1/+1
It's never a good idea to put provided buffers without notifying the userspace, it'll lead to userspace leaks, so add io_put_kbuf() in io_req_complete_failed(). The fail helper is called by all sorts of requests, but it's still safe to do as io_put_kbuf() will return 0 in for all requests that don't support and so don't expect provided buffers. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/a4880106fcf199d5810707fe2d17126fcdf18bc4.1647481208.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17io_uring: refactor timeout cancellation cqe postingPavel Begunkov1-4/+1
io_fill_cqe*() is not always the best way to post CQEs just because there is enough of infrastructure on top. Replace a raw call to a variant of it inside of io_timeout_cancel(), which also saves us some bloating and might help with batching later. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/46113ec4345764b4aef3b384ce38cceabaeedcbb.1647481208.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-17io_uring: normilise naming for fill_cqe*Pavel Begunkov1-8/+8
Restore consistency in __io_fill_cqe* like helpers, always honouring "io_" prefix and adding "req" when we're passing in a request. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/bd016ff5c1a4f74687828069d2619d8a65e0c6d7.1647481208.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-16io_uring: cache poll/double-poll state with a request flagJens Axboe1-5/+19
With commit "io_uring: cache req->apoll->events in req->cflags" applied, we now have just io_poll_remove_entries() dipping into req->apoll when it isn't strictly necessary. Mark poll and double-poll with a flag, so we know if we need to look at apoll->double_poll. This avoids pulling in those cachelines if we don't need them. The common case is that the poll wake handler already removed these entries while hot off the completion path. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-16io_uring: cache req->apoll->events in req->cflagsJens Axboe1-12/+19
When we arm poll on behalf of a different type of request, like a network receive, then we allocate req->apoll as our poll entry. Running network workloads shows io_poll_check_events() as the most expensive part of io_uring, and it's all due to having to pull in req->apoll instead of just the request which we have hot already. Cache poll->events in req->cflags, which isn't used until the request completes anyway. This isn't strictly needed for regular poll, where req->poll.events is used and thus already hot, but for the sake of unification we do it all around. This saves 3-4% of overhead in certain request workloads. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-16docs/kernel-parameters: update description of mem=Mike Rapoport1-0/+18
The existing description of mem= does not cover all the cases and differences between how architectures treat it. Extend the description to match the code. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/r/20220310082736.1346366-1-rppt@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-03-16parisc: Avoid calling SMP cache flush functions on cache-less machinesHelge Deller3-34/+40
At least the qemu virtual machine does not provide D- and I-caches, so skip triggering SMP irqs to flush caches on such machines. Further optimize the caching code by using static branches and making some functions static. Signed-off-by: Helge Deller <deller@gmx.de>