BMC/Intel-BMC/linux.git/kernel, branch dev-5.15-intel

perf/core: Fix perf_mmap fail when CONFIG_PERF_USE_VMALLOC enabled

2022-04-27T12:38:58+00:00

[ Upstream commit 60490e7966659b26d74bf1fa4aa8693d9a94ca88 ] This problem can be reproduced with CONFIG_PERF_USE_VMALLOC enabled on both x86_64 and aarch64 arch when using sysdig -B(using ebpf)[1]. sysdig -B works fine after rebuilding the kernel with CONFIG_PERF_USE_VMALLOC disabled. I tracked it down to the if condition event->rb->nr_pages != nr_pages in perf_mmap is true when CONFIG_PERF_USE_VMALLOC is enabled where event->rb->nr_pages = 1 and nr_pages = 2048 resulting perf_mmap to return -EINVAL. This is because when CONFIG_PERF_USE_VMALLOC is enabled, rb->nr_pages is always equal to 1. Arch with CONFIG_PERF_USE_VMALLOC enabled by default: arc/arm/csky/mips/sh/sparc/xtensa Arch with CONFIG_PERF_USE_VMALLOC disabled by default: x86_64/aarch64/... Fix this problem by using data_page_nr() [1] https://github.com/draios/sysdig Fixes: 906010b2134e ("perf_event: Provide vmalloc() based mmap() backing") Signed-off-by: Zhipeng Xie Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220209145417.6495-1-xiezhipeng1@huawei.com Signed-off-by: Sasha Levin

sched/pelt: Fix attach_entity_load_avg() corner case

2022-04-27T12:38:58+00:00

[ Upstream commit 40f5aa4c5eaebfeaca4566217cb9c468e28ed682 ] The warning in cfs_rq_is_decayed() triggered: SCHED_WARN_ON(cfs_rq->avg.load_avg || cfs_rq->avg.util_avg || cfs_rq->avg.runnable_avg) There exists a corner case in attach_entity_load_avg() which will cause load_sum to be zero while load_avg will not be. Consider se_weight is 88761 as per the sched_prio_to_weight[] table. Further assume the get_pelt_divider() is 47742, this gives: se->avg.load_avg is 1. However, calculating load_sum: se->avg.load_sum = div_u64(se->avg.load_avg * se->avg.load_sum, se_weight(se)); se->avg.load_sum = 1*47742/88761 = 0. Then enqueue_load_avg() adds this to the cfs_rq totals: cfs_rq->avg.load_avg += se->avg.load_avg; cfs_rq->avg.load_sum += se_weight(se) * se->avg.load_sum; Resulting in load_avg being 1 with load_sum is 0, which will trigger the WARN. Fixes: f207934fb79d ("sched/fair: Align PELT windows between cfs_rq and its se") Signed-off-by: kuyo chang [peterz: massage changelog] Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Vincent Guittot Tested-by: Dietmar Eggemann Link: https://lkml.kernel.org/r/20220414090229.342-1-kuyo.chang@mediatek.com Signed-off-by: Sasha Levin

dma-mapping: remove bogus test for pfn_valid from dma_map_resource

2022-04-27T12:38:50+00:00

commit a9c38c5d267cb94871dfa2de5539c92025c855d7 upstream. dma_map_resource() uses pfn_valid() to ensure the range is not RAM. However, pfn_valid() only checks for availability of the memory map for a PFN but it does not ensure that the PFN is actually backed by RAM. As dma_map_resource() is the only method in DMA mapping APIs that has this check, simply drop the pfn_valid() test from dma_map_resource(). Link: https://lore.kernel.org/all/20210824173741.GC623@arm.com/ Signed-off-by: Mike Rapoport Reviewed-by: Christoph Hellwig Acked-by: David Hildenbrand Link: https://lore.kernel.org/r/20210930013039.11260-2-rppt@kernel.org Signed-off-by: Will Deacon Fixes: 859a85ddf90e ("mm: remove pfn_valid_within() and CONFIG_HOLES_IN_ZONE") Link: https://lore.kernel.org/r/Yl0IZWT2nsiYtqBT@linux.ibm.com Signed-off-by: Georgi Djakov Signed-off-by: Greg Kroah-Hartman

cpu/hotplug: Remove the 'cpu' member of cpuhp_cpu_state

2022-04-20T07:34:21+00:00

commit b7ba6d8dc3569e49800ef0136799f26f43e237e8 upstream. Currently the setting of the 'cpu' member of struct cpuhp_cpu_state in cpuhp_create() is too late as it is used earlier in _cpu_up(). If kzalloc_node() in __smpboot_create_thread() fails then the rollback will be done with st->cpu==0 causing CPU0 to be erroneously set to be dying, causing the scheduler to get mightily confused and throw its toys out of the pram. However the cpu number is actually available directly, so simply remove the 'cpu' member and avoid the problem in the first place. Fixes: 2ea46c6fc945 ("cpumask/hotplug: Fix cpu_dying() state tracking") Signed-off-by: Steven Price Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20220411152233.474129-2-steven.price@arm.com Signed-off-by: Greg Kroah-Hartman

dma-direct: avoid redundant memory sync for swiotlb

2022-04-20T07:34:21+00:00

commit 9e02977bfad006af328add9434c8bffa40e053bb upstream. When we looked into FIO performance with swiotlb enabled in VM, we found swiotlb_bounce() is always called one more time than expected for each DMA read request. It turns out that the bounce buffer is copied to original DMA buffer twice after the completion of a DMA request (one is done by in dma_direct_sync_single_for_cpu(), the other by swiotlb_tbl_unmap_single()). But the content in bounce buffer actually doesn't change between the two rounds of copy. So, one round of copy is redundant. Pass DMA_ATTR_SKIP_CPU_SYNC flag to swiotlb_tbl_unmap_single() to skip the memory copy in it. This fix increases FIO 64KB sequential read throughput in a guest with swiotlb=force by 5.6%. Fixes: 55897af63091 ("dma-direct: merge swiotlb_dma_ops into the dma_direct code") Reported-by: Wang Zhaoyang1 Reported-by: Gao Liang Signed-off-by: Chao Gao Reviewed-by: Kevin Tian Signed-off-by: Christoph Hellwig Signed-off-by: Greg Kroah-Hartman

timers: Fix warning condition in __run_timers()

2022-04-20T07:34:21+00:00

commit c54bc0fc84214b203f7a0ebfd1bd308ce2abe920 upstream. When the timer base is empty, base::next_expiry is set to base::clk + NEXT_TIMER_MAX_DELTA and base::next_expiry_recalc is false. When no timer is queued until jiffies reaches base::next_expiry value, the warning for not finding any expired timer and base::next_expiry_recalc is false in __run_timers() triggers. To prevent triggering the warning in this valid scenario base::timers_pending needs to be added to the warning condition. Fixes: 31cd0e119d50 ("timers: Recalculate next timer interrupt only when necessary") Reported-by: Johannes Berg Signed-off-by: Anna-Maria Behnsen Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Link: https://lore.kernel.org/r/20220405191732.7438-3-anna-maria@linutronix.de Signed-off-by: Greg Kroah-Hartman

smp: Fix offline cpu check in flush_smp_call_function_queue()

2022-04-20T07:34:21+00:00

commit 9e949a3886356fe9112c6f6f34a6e23d1d35407f upstream. The check in flush_smp_call_function_queue() for callbacks that are sent to offline CPUs currently checks whether the queue is empty. However, flush_smp_call_function_queue() has just deleted all the callbacks from the queue and moved all the entries into a local list. This checks would only be positive if some callbacks were added in the short time after llist_del_all() was called. This does not seem to be the intention of this check. Change the check to look at the local list to which the entries were moved instead of the queue from which all the callbacks were just removed. Fixes: 8d056c48e4862 ("CPU hotplug, smp: flush any pending IPI callbacks before CPU offline") Signed-off-by: Nadav Amit Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20220319072015.1495036-1-namit@vmware.com Signed-off-by: Greg Kroah-Hartman

tick/nohz: Use WARN_ON_ONCE() to prevent console saturation

2022-04-20T07:34:20+00:00

commit 40e97e42961f8c6cc7bd5fe67cc18417e02d78f1 upstream. While running some testing on code that happened to allow the variable tick_nohz_full_running to get set but with no "possible" NOHZ cores to back up that setting, this warning triggered: if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE)) WARN_ON(tick_nohz_full_running); The console was overwhemled with an endless stream of one WARN per tick per core and there was no way to even see what was going on w/o using a serial console to capture it and then trace it back to this. Change it to WARN_ON_ONCE(). Fixes: 08ae95f4fd3b ("nohz_full: Allow the boot CPU to be nohz_full") Signed-off-by: Paul Gortmaker Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20211206145950.10927-3-paul.gortmaker@windriver.com Signed-off-by: Greg Kroah-Hartman

genirq/affinity: Consider that CPUs on nodes can be unbalanced

2022-04-20T07:34:20+00:00

commit 08d835dff916bfe8f45acc7b92c7af6c4081c8a7 upstream. If CPUs on a node are offline at boot time, the number of nodes is different when building affinity masks for present cpus and when building affinity masks for possible cpus. This causes the following problem: In the case that the number of vectors is less than the number of nodes there are cases where bits of masks for present cpus are overwritten when building masks for possible cpus. Fix this by excluding CPUs, which are not part of the current build mask (present/possible). [ tglx: Massaged changelog and added comment ] Fixes: b82592199032 ("genirq/affinity: Spread IRQs to all available NUMA nodes") Signed-off-by: Rei Yamamoto Signed-off-by: Thomas Gleixner Reviewed-by: Ming Lei Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220331003309.10891-1-yamamoto.rei@jp.fujitsu.com Signed-off-by: Greg Kroah-Hartman

stacktrace: move filter_irq_stacks() to kernel/stacktrace.c

2022-04-13T18:59:28+00:00

commit f39f21b3ddc7fc0f87eb6dc75ddc81b5bbfb7672 upstream. filter_irq_stacks() has little to do with the stackdepot implementation, except that it is usually used by users (such as KASAN) of stackdepot to reduce the stack trace. However, filter_irq_stacks() itself is not useful without a stack trace as obtained by stack_trace_save() and friends. Therefore, move filter_irq_stacks() to kernel/stacktrace.c, so that new users of filter_irq_stacks() do not have to start depending on STACKDEPOT only for filter_irq_stacks(). Link: https://lkml.kernel.org/r/20210923104803.2620285-1-elver@google.com Signed-off-by: Marco Elver Acked-by: Dmitry Vyukov Cc: Alexander Potapenko Cc: Jann Horn Cc: Aleksandr Nogikh Cc: Taras Madan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman