- 01 Feb, 2019 27 commits
-
-
Dan Carpenter authored
There is a copy and paste bug so we set "config->test_driver" to NULL twice instead of setting "config->test_fs". Smatch complains that it leads to a double free: lib/test_kmod.c:840 __kmod_config_init() warn: 'config->test_fs' double freed Link: http://lkml.kernel.org/r/20190121140011.GA14283@kadam Fixes: d9c6a72d ("kmod: add test driver to stress test the module loader") Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Acked-by:
Luis Chamberlain <mcgrof@kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Shakeel Butt authored
Syzbot instance running on upstream kernel found a use-after-free bug in oom_kill_process. On further inspection it seems like the process selected to be oom-killed has exited even before reaching read_lock(&tasklist_lock) in oom_kill_process(). More specifically the tsk->usage is 1 which is due to get_task_struct() in oom_evaluate_task() and the put_task_struct within for_each_thread() frees the tsk and for_each_thread() tries to access the tsk. The easiest fix is to do get/put across the for_each_thread() on the selected task. Now the next question is should we continue with the oom-kill as the previously selected task has exited? However before adding more complexity and heuristics, let's answer why we even look at the children of oom-kill selected task? The select_bad_process() has already selected the worst process in the system/memcg. Due to race, the selected process might not be the worst at the kill time but does that matter? The userspace can use the oom_score_adj interface to prefer children to be killed before the parent. I looked at the history but it seems like this is there before git history. Link: http://lkml.kernel.org/r/20190121215850.221745-1-shakeelb@google.com Reported-by: syzbot+7fbbfa368521945f0e3d@syzkaller.appspotmail.com Fixes: 6b0c81b3 ("mm, oom: reduce dependency on tasklist_lock") Signed-off-by:
Shakeel Butt <shakeelb@google.com> Reviewed-by:
Roman Gushchin <guro@fb.com> Acked-by:
Michal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: <stable@vger.kernel.org> Signed-off-by:
-
Qian Cai authored
On an arm64 ThunderX2 server, the first kmemleak scan would crash [1] with CONFIG_DEBUG_VM_PGFLAGS=y due to page_to_nid() found a pfn that is not directly mapped (MEMBLOCK_NOMAP). Hence, the page->flags is uninitialized. This is due to the commit 9f1eb38e ("mm, kmemleak: little optimization while scanning") starts to use pfn_to_online_page() instead of pfn_valid(). However, in the CONFIG_MEMORY_HOTPLUG=y case, pfn_to_online_page() does not call memblock_is_map_memory() while pfn_valid() does. Historically, the commit 68709f45 ("arm64: only consider memblocks with NOMAP cleared for linear mapping") causes pages marked as nomap being no long reassigned to the new zone in memmap_init_zone() by calling __init_single_page(). Since the commit 2d070eab ("mm: consider zone which is not fully populated to have holes") introduced pfn_to_online_page() and was designed to return a valid pfn only, but it is clearly broken on arm64. Therefore, let pfn_to_online_page() call pfn_valid_within(), so it can handle nomap thanks to the commit f52bb98f ("arm64: mm: always enable CONFIG_HOLES_IN_ZONE"), while it will be optimized away on architectures where have no HOLES_IN_ZONE. [1] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000006 Mem abort info: ESR = 0x96000005 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000005 CM = 0, WnR = 0 Internal error: Oops: 96000005 [#1] SMP CPU: 60 PID: 1408 Comm: kmemleak Not tainted 5.0.0-rc2+ #8 pstate: 60400009 (nZCv daif +PAN -UAO) pc : page_mapping+0x24/0x144 lr : __dump_page+0x34/0x3dc sp : ffff00003a5cfd10 x29: ffff00003a5cfd10 x28: 000000000000802f x27: 0000000000000000 x26: 0000000000277d00 x25: ffff000010791f56 x24: ffff7fe000000000 x23: ffff000010772f8b x22: ffff00001125f670 x21: ffff000011311000 x20: ffff000010772f8b x19: fffffffffffffffe x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: ffff802698b19600 x13: ffff802698b1a200 x12: ffff802698b16f00 x11: ffff802698b1a400 x10: 0000000000001400 x9 : 0000000000000001 x8 : ffff00001121a000 x7 : 0000000000000000 x6 : ffff0000102c53b8 x5 : 0000000000000000 x4 : 0000000000000003 x3 : 0000000000000100 x2 : 0000000000000000 x1 : ffff000010772f8b x0 : ffffffffffffffff Process kmemleak (pid: 1408, stack limit = 0x(____ptrval____)) Call trace: page_mapping+0x24/0x144 __dump_page+0x34/0x3dc dump_page+0x28/0x4c kmemleak_scan+0x4ac/0x680 kmemleak_scan_thread+0xb4/0xdc kthread+0x12c/0x13c ret_from_fork+0x10/0x18 Code: d503201f f9400660 36000040 d1000413 (f9400661) ---[ end trace 4d4bd7f573490c8e ]--- Kernel panic - not syncing: Fatal exception SMP: stopping secondary CPUs Kernel Offset: disabled CPU features: 0x002,20000c38 Memory Limit: none ---[ end Kernel panic - not syncing: Fatal exception ]--- Link: http://lkml.kernel.org/r/20190122132916.28360-1-cai@lca.pw Fixes: 9f1eb38e ("mm, kmemleak: little optimization while scanning") Signed-off-by:
Qian Cai <cai@lca.pw> Acked-by:
-
Oscar Salvador authored
This is the same sort of error we saw in commit 17e2e7d7 ("mm, page_alloc: fix has_unmovable_pages for HugePages"). Gigantic hugepages cross several memblocks, so it can be that the page we get in scan_movable_pages() is a page-tail belonging to a 1G-hugepage. If that happens, page_hstate()->size_to_hstate() will return NULL, and we will blow up in hugepage_migration_supported(). The splat is as follows: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 #PF error: [normal kernel read fault] PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 1 PID: 1350 Comm: bash Tainted: G E 5.0.0-rc1-mm1-1-default+ #27 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014 RIP: 0010:__offline_pages+0x6ae/0x900 Call Trace: memory_subsys_offline+0x42/0x60 device_offline+0x80/0xa0 state_store+0xab/0xc0 kernfs_fop_write+0x102/0x180 __vfs_write+0x26/0x190 vfs_write+0xad/0x1b0 ksys_write+0x42/0x90 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Modules linked in: af_packet(E) xt_tcpudp(E) ipt_REJECT(E) xt_conntrack(E) nf_conntrack(E) nf_defrag_ipv4(E) ip_set(E) nfnetlink(E) ebtable_nat(E) ebtable_broute(E) bridge(E) stp(E) llc(E) iptable_mangle(E) iptable_raw(E) iptable_security(E) ebtable_filter(E) ebtables(E) iptable_filter(E) ip_tables(E) x_tables(E) kvm_intel(E) kvm(E) irqbypass(E) crct10dif_pclmul(E) crc32_pclmul(E) ghash_clmulni_intel(E) bochs_drm(E) ttm(E) aesni_intel(E) drm_kms_helper(E) aes_x86_64(E) crypto_simd(E) cryptd(E) glue_helper(E) drm(E) virtio_net(E) syscopyarea(E) sysfillrect(E) net_failover(E) sysimgblt(E) pcspkr(E) failover(E) i2c_piix4(E) fb_sys_fops(E) parport_pc(E) parport(E) button(E) btrfs(E) libcrc32c(E) xor(E) zstd_decompress(E) zstd_compress(E) xxhash(E) raid6_pq(E) sd_mod(E) ata_generic(E) ata_piix(E) ahci(E) libahci(E) libata(E) crc32c_intel(E) serio_raw(E) virtio_pci(E) virtio_ring(E) virtio(E) sg(E) scsi_mod(E) autofs4(E) [akpm@linux-foundation.org: fix brace layout, per David. Reduce indentation] Link: http://lkml.kernel.org/r/20190122154407.18417-1-osalvador@suse.deSigned-off-by:
Oscar Salvador <osalvador@suse.de> Reviewed-by:
Anthony Yznaga <anthony.yznaga@oracle.com> Acked-by:
David Hildenbrand <david@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by:
-
Johannes Weiner authored
psi has provisions to shut off the periodic aggregation worker when there is a period of no task activity - and thus no data that needs aggregating. However, while developing psi monitoring, Suren noticed that the aggregation clock currently won't stay shut off for good. Debugging this revealed a flaw in the idle design: an aggregation run will see no task activity and decide to go to sleep; shortly thereafter, the kworker thread that executed the aggregation will go idle and cause a scheduling change, during which the psi callback will kick the !pending worker again. This will ping-pong forever, and is equivalent to having no shut-off logic at all (but with more code!) Fix this by exempting aggregation workers from psi's clock waking logic when the state change is them going to sleep. To do this, tag workers with the last work function they executed, and if in psi we see a worker going to sleep after aggregating psi data, we will not reschedule the aggregation work item. What if the worker is also executing other items before or after? Any psi state times that were incurred by work items preceding the aggregation work will have been collected from the per-cpu buckets during the aggregation itself. If there are work items following the aggregation work, the worker's last_func tag will be overwritten and the aggregator will be kept alive to process this genuine new activity. If the aggregation work is the last thing the worker does, and we decide to go idle, the brief period of non-idle time incurred between the aggregation run and the kworker's dequeue will be stranded in the per-cpu buckets until the clock is woken by later activity. But that should not be a problem. The buckets can hold 4s worth of time, and future activity will wake the clock with a 2s delay, giving us 2s worth of data we can leave behind when disabling aggregation. If it takes a worker more than two seconds to go idle after it finishes its last work item, we likely have bigger problems in the system, and won't notice one sample that was averaged with a bogus per-CPU weight. Link: http://lkml.kernel.org/r/20190116193501.1910-1-hannes@cmpxchg.org Fixes: eb414681 ("psi: pressure stall information for CPU, memory, and IO") Signed-off-by:
Johannes Weiner <hannes@cmpxchg.org> Reported-by:
Suren Baghdasaryan <surenb@google.com> Acked-by:
Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by:
-
Mikhail Zaslonko authored
If memory end is not aligned with the sparse memory section boundary, the mapping of such a section is only partly initialized. This may lead to VM_BUG_ON due to uninitialized struct pages access from test_pages_in_a_zone() function triggered by memory_hotplug sysfs handlers. Here are the the panic examples: CONFIG_DEBUG_VM_PGFLAGS=y kernel parameter mem=2050M -------------------------- page:000003d082008000 is uninitialized and poisoned page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p)) Call Trace: test_pages_in_a_zone+0xde/0x160 show_valid_zones+0x5c/0x190 dev_attr_show+0x34/0x70 sysfs_kf_seq_show+0xc8/0x148 seq_read+0x204/0x480 __vfs_read+0x32/0x178 vfs_read+0x82/0x138 ksys_read+0x5a/0xb0 system_call+0xdc/0x2d8 Last Breaking-Event-Address: test_pages_in_a_zone+0xde/0x160 Kernel panic - not syncing: Fatal exception: panic_on_oops Fix this by checking whether the pfn to check is within the zone. [mhocko@suse.com: separated this change from http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com] Link: http://lkml.kernel.org/r/20190128144506.15603-3-mhocko@kernel.org [mhocko@suse.com: separated this change from http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com] Signed-off-by:
Mikhail Zaslonko <zaslonko@linux.ibm.com> Tested-by:
Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Reviewed-by:
Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by:
-
Michal Hocko authored
Patch series "mm, memory_hotplug: fix uninitialized pages fallouts", v2. Mikhail Zaslonko has posted fixes for the two bugs quite some time ago [1]. I have pushed back on those fixes because I believed that it is much better to plug the problem at the initialization time rather than play whack-a-mole all over the hotplug code and find all the places which expect the full memory section to be initialized. We have ended up with commit 2830bf6f ("mm, memory_hotplug: initialize struct pages for the full memory section") merged and cause a regression [2][3]. The reason is that there might be memory layouts when two NUMA nodes share the same memory section so the merged fix is simply incorrect. In order to plug this hole we really have to be zone range aware in those handlers. I have split up the original patch into two. One is unchanged (patch 2) and I took a different approach for `removable' crash. [1] http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com [2] https://bugzilla.redhat.com/show_bug.cgi?id=1666948 [3] http://lkml.kernel.org/r/20190125163938.GA20411@dhcp22.suse.cz This patch (of 2): Mikhail has reported the following VM_BUG_ON triggered when reading sysfs removable state of a memory block: page:000003d08300c000 is uninitialized and poisoned page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p)) Call Trace: is_mem_section_removable+0xb4/0x190 show_mem_removable+0x9a/0xd8 dev_attr_show+0x34/0x70 sysfs_kf_seq_show+0xc8/0x148 seq_read+0x204/0x480 __vfs_read+0x32/0x178 vfs_read+0x82/0x138 ksys_read+0x5a/0xb0 system_call+0xdc/0x2d8 Last Breaking-Event-Address: is_mem_section_removable+0xb4/0x190 Kernel panic - not syncing: Fatal exception: panic_on_oops The reason is that the memory block spans the zone boundary and we are stumbling over an unitialized struct page. Fix this by enforcing zone range in is_mem_section_removable so that we never run away from a zone. Link: http://lkml.kernel.org/r/20190128144506.15603-2-mhocko@kernel.orgSigned-off-by:
-
Tetsuo Handa authored
Arkadiusz reported that enabling memcg's group oom killing causes strange memcg statistics where there is no task in a memcg despite the number of tasks in that memcg is not 0. It turned out that there is a bug in wake_oom_reaper() which allows enqueuing same task twice which makes impossible to decrease the number of tasks in that memcg due to a refcount leak. This bug existed since the OOM reaper became invokable from task_will_free_mem(current) path in out_of_memory() in Linux 4.7, T1@P1 |T2@P1 |T3@P1 |OOM reaper ----------+----------+----------+------------ # Processing an OOM victim in a different memcg domain. try_charge() mem_cgroup_out_of_memory() mutex_lock(&oom_lock) try_charge() mem_cgroup_out_of_memory() mutex_lock(&oom_lock) try_charge() mem_cgroup_out_of_memory() mutex_lock(&oom_lock) out_of_memory() oom_kill_process(P1) do_send_sig_info(SIGKILL, @P1) mark_oom_victim(T1@P1) wake_oom_reaper(T1@P1) # T1@P1 is enqueued. mutex_unlock(&oom_lock) out_of_memory() mark_oom_victim(T2@P1) wake_oom_reaper(T2@P1) # T2@P1 is enqueued. mutex_unlock(&oom_lock) out_of_memory() mark_oom_victim(T1@P1) wake_oom_reaper(T1@P1) # T1@P1 is enqueued again due to oom_reaper_list == T2@P1 && T1@P1->oom_reaper_list == NULL. mutex_unlock(&oom_lock) # Completed processing an OOM victim in a different memcg domain. spin_lock(&oom_reaper_lock) # T1P1 is dequeued. spin_unlock(&oom_reaper_lock) but memcg's group oom killing made it easier to trigger this bug by calling wake_oom_reaper() on the same task from one out_of_memory() request. Fix this bug using an approach used by commit 855b0183 ("oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task"). As a side effect of this patch, this patch also avoids enqueuing multiple threads sharing memory via task_will_free_mem(current) path. Link: http://lkml.kernel.org/r/e865a044-2c10-9858-f4ef-254bc71d6cc2@i-love.sakura.ne.jp Link: http://lkml.kernel.org/r/5ee34fc6-1485-34f8-8790-903ddabaa809@i-love.sakura.ne.jp Fixes: af8e15cc ("oom, oom_reaper: do not enqueue task if it is on the oom_reaper_list head") Signed-off-by:Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by:
Arkadiusz Miskiewicz <arekm@maven.pl> Tested-by:
-
Jan Kara authored
Currently, buffer_migrate_page_norefs() was constantly failing because buffer_migrate_lock_buffers() grabbed reference on each buffer. In fact, there's no reason for buffer_migrate_lock_buffers() to grab any buffer references as the page is locked during all our operation and thus nobody can reclaim buffers from the page. So remove grabbing of buffer references which also makes buffer_migrate_page_norefs() succeed. Link: http://lkml.kernel.org/r/20190116131217.7226-1-jack@suse.cz Fixes: 89cb0888 "mm: migrate: provide buffer_migrate_page_norefs()" Signed-off-by:
Jan Kara <jack@suse.cz> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> Signed-off-by:
-
Andrei Vagin authored
Currently, exit_ptrace() adds all ptraced tasks in a dead list, then zap_pid_ns_processes() waits on all tasks in a current pidns, and only then are tasks from the dead list released. zap_pid_ns_processes() can get stuck on waiting tasks from the dead list. In this case, we will have one unkillable process with one or more dead children. Thanks to Oleg for the advice to release tasks in find_child_reaper(). Link: http://lkml.kernel.org/r/20190110175200.12442-1-avagin@gmail.com Fixes: 7c8bd232 ("exit: ptrace: shift "reap dead" code from exit_ptrace() to forget_original_parent()") Signed-off-by:
Andrei Vagin <avagin@gmail.com> Signed-off-by:
Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by:
-
Qian Cai authored
If the kernel is configured with KASAN_EXTRA, the stack size is increasted significantly because this option sets "-fstack-reuse" to "none" in GCC [1]. As a result, it triggers stack overrun quite often with 32k stack size compiled using GCC 8. For example, this reproducer https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/syscalls/madvise/madvise06.c triggers a "corrupted stack end detected inside scheduler" very reliably with CONFIG_SCHED_STACK_END_CHECK enabled. There are just too many functions that could have a large stack with KASAN_EXTRA due to large local variables that have been called over and over again without being able to reuse the stacks. Some noticiable ones are size 7648 shrink_page_list 3584 xfs_rmap_convert 3312 migrate_page_move_mapping 3312 dev_ethtool 3200 migrate_misplaced_transhuge_page 3168 copy_process There are other 49 functions are over 2k in size while compiling kernel with "-Wframe-larger-than=" even with a related minimal config on this machine. Hence, it is too much work to change Makefiles for each object to compile without "-fsanitize-address-use-after-scope" individually. [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715#c23 Although there is a patch in GCC 9 to help the situation, GCC 9 probably won't be released in a few months and then it probably take another 6-month to 1-year for all major distros to include it as a default. Hence, the stack usage with KASAN_EXTRA can be revisited again in 2020 when GCC 9 is everywhere. Until then, this patch will help users avoid stack overrun. This has already been fixed for arm64 for the same reason via 6e883067 ("arm64: kasan: Increase stack size for KASAN_EXTRA"). Link: http://lkml.kernel.org/r/20190109215209.2903-1-cai@lca.pwSigned-off-by:
-
Andrea Arcangeli authored
hugetlb needs the same fix as faultin_nopage (which was applied in commit 96312e61 ("mm/gup.c: teach get_user_pages_unlocked to handle FOLL_NOWAIT")) or KVM hangs because it thinks the mmap_sem was already released by hugetlb_fault() if it returned VM_FAULT_RETRY, but it wasn't in the FOLL_NOWAIT case. Link: http://lkml.kernel.org/r/20190109020203.26669-2-aarcange@redhat.com Fixes: ce53053c ("kvm: switch get_user_page_nowait() to get_user_pages_unlocked()") Signed-off-by:
Andrea Arcangeli <aarcange@redhat.com> Tested-by:
"Dr. David Alan Gilbert" <dgilbert@redhat.com> Reported-by:
Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by:
Peter Xu <peterx@redhat.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by:
-
Masahiro Yamada authored
Most architectures do not export shmparam.h to user-space. $ find arch -name shmparam.h | sort arch/alpha/include/asm/shmparam.h arch/arc/include/asm/shmparam.h arch/arm64/include/asm/shmparam.h arch/arm/include/asm/shmparam.h arch/csky/include/asm/shmparam.h arch/ia64/include/asm/shmparam.h arch/mips/include/asm/shmparam.h arch/nds32/include/asm/shmparam.h arch/nios2/include/asm/shmparam.h arch/parisc/include/asm/shmparam.h arch/powerpc/include/asm/shmparam.h arch/s390/include/asm/shmparam.h arch/sh/include/asm/shmparam.h arch/sparc/include/asm/shmparam.h arch/x86/include/asm/shmparam.h arch/xtensa/include/asm/shmparam.h Strangely, some users of the asm-generic wrapper export shmparam.h $ git grep 'generic-y += shmparam.h' arch/c6x/include/uapi/asm/Kbuild:generic-y += shmparam.h arch/h8300/include/uapi/asm/Kbuild:generic-y += shmparam.h arch/hexagon/include/uapi/asm/Kbuild:generic-y += shmparam.h arch/m68k/include/uapi/asm/Kbuild:generic-y += shmparam.h arch/microblaze/include/uapi/asm/Kbuild:generic-y += shmparam.h arch/openrisc/include/uapi/asm/Kbuild:generic-y += shmparam.h arch/riscv/include/asm/Kbuild:generic-y += shmparam.h arch/unicore32/include/uapi/asm/Kbuild:generic-y += shmparam.h The newly added riscv correctly creates the asm-generic wrapper in the kernel space, but the others (c6x, h8300, hexagon, m68k, microblaze, openrisc, unicore32) create the one in the uapi directory. Digging into the git history, now I guess fcc8487d ("uapi: export all headers under uapi directories") was the misconversion. Prior to that commit, no architecture exported to shmparam.h As its commit description said, that commit exported shmparam.h for c6x, h8300, hexagon, m68k, openrisc, unicore32. 83f0124a ("microblaze: remove asm-generic wrapper headers") accidentally exported shmparam.h for microblaze. This commit unexports shmparam.h for those architectures. There is no more reason to export include/uapi/asm-generic/shmparam.h, so it has been moved to include/asm-generic/shmparam.h Link: http://lkml.kernel.org/r/1546904307-11124-1-git-send-email-yamada.masahiro@socionext.comSigned-off-by:
Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by:
Stafford Horne <shorne@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Guo Ren <guoren@kernel.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Mark Salter <msalter@redhat.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Vincent Chen <deanbo422@gmail.com> Signed-off-by:
-
Alexey Dobriyan authored
/proc entries under /proc/net/* can't be cached into dcache because setns(2) can change current net namespace. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: avoid vim miscolorization] [adobriyan@gmail.com: write test, add dummy ->d_revalidate hook: necessary if /proc/net/* is pinned at setns time] Link: http://lkml.kernel.org/r/20190108192350.GA12034@avx2 Link: http://lkml.kernel.org/r/20190107162336.GA9239@avx2 Fixes: 1da4d377 ("proc: revalidate misc dentries") Signed-off-by:
Alexey Dobriyan <adobriyan@gmail.com> Reported-by:
Mateusz Stępień <mateusz.stepien@netrounds.com> Reported-by:
Ahmad Fatoum <a.fatoum@pengutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
-
Oscar Salvador authored
do_migrate_range() takes a memory range and tries to isolate the pages to put them into a list. This list will be later on used in migrate_pages() to know the pages we need to migrate. Currently, if we fail to isolate a single page, we put all already isolated pages back to their LRU and we bail out from the function. This is quite suboptimal, as this will force us to start over again because scan_movable_pages will give us the same range. If there is no chance that we can isolate that page, we will loop here forever. Issue debugged in [1] has proved that. During the debugging of that issue, it was noticed that if do_migrate_ranges() fails to isolate a single page, we will just discard the work we have done so far and bail out, which means that scan_movable_pages() will find again the same set of pages. Instead, we can just skip the error, keep isolating as much pages as possible and then proceed with the call to migrate_pages(). This will allow us to do as much work as possible at once. [1] https://lkml.org/lkml/2018/12/6/324 Michal said: : I still think that this doesn't give us a whole picture. Looping for : ever is a bug. Failing the isolation is quite possible and it should : be a ephemeral condition (e.g. a race with freeing the page or : somebody else isolating the page for whatever reason). And here comes : the disadvantage of the current implementation. We simply throw : everything on the floor just because of a ephemeral condition. The : racy page_count check is quite dubious to prevent from that. Link: http://lkml.kernel.org/r/20181211135312.27034-1-osalvador@suse.deSigned-off-by:
-
git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds authored
Pull rdma fixes from Jason Gunthorpe: "Still not much going on, the usual set of oops and driver fixes this time: - Fix two uapi breakage regressions in mlx5 drivers - Various oops fixes in hfi1, mlx4, umem, uverbs, and ipoib - A protocol bug fix for hfi1 preventing it from implementing the verbs API properly, and a compatability fix for EXEC STACK user programs - Fix missed refcounting in the 'advise_mr' patches merged this cycle. - Fix wrong use of the uABI in the hns SRQ patches merged this cycle" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: IB/uverbs: Fix OOPs in uverbs_user_mmap_disassociate IB/ipoib: Fix for use-after-free in ipoib_cm_tx_start IB/uverbs: Fix ioctl query port to consider device disassociation RDMA/mlx5: Fix flow creation on representors IB/uverbs: Fix OOPs upon device disassociation RDMA/umem: Add missing initialization of owning_mm RDMA/hns: Update the kernel header file of hns IB/mlx5: Fix how advise_mr() launches async work RDMA/device: Expose ib_device_try_get(() IB/hfi1: Add limit test for RC/UC send via loopback IB/hfi1: Remove overly conservative VM_EXEC flag check IB/{hfi1, qib}: Fix WC.byte_len calculation for UD_SEND_WITH_IMM IB/mlx4: Fix using wrong function to destroy sqp AHs under SRIOV RDMA/mlx5: Fix check for supported user flags when creating a QP -
git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds authored
Pull iomap fixes from Darrick Wong: "A couple of iomap fixes to eliminate some memory corruption and hang problems that were reported: - fix page migration when using iomap for pagecache management - fix a use-after-free bug in the directio code" * tag 'iomap-5.0-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: iomap: fix a use after free in iomap_dio_rw iomap: get/put the page in iomap_page_create/release()
-
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds authored
Pull power management fixes from Rafael Wysocki: "These fix a PM-runtime framework regression introduced by the recent switch-over of device autosuspend to hrtimers and a mistake in the "poll idle state" code introduced by a recent change in it. Specifics: - Since ktime_get() turns out to be problematic for device autosuspend in the PM-runtime framework, make it use ktime_get_mono_fast_ns() instead (Vincent Guittot). - Fix an initial value of a local variable in the "poll idle state" code that makes it behave not exactly as expected when all idle states except for the "polling" one are disabled (Doug Smythies)" * tag 'pm-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpuidle: poll_state: Fix default time limit PM-runtime: Fix deadlock with ktime_get() -
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds authored
Pull ACPI Kconfig fixes from Rafael Wysocki: "Prevent invalid configurations from being created (e.g. by randconfig) due to some ACPI-related Kconfig options' dependencies that are not specified directly (Sinan Kaya)" * tag 'acpi-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: platform/x86: Fix unmet dependency warning for SAMSUNG_Q10 platform/x86: Fix unmet dependency warning for ACPI_CMPC mfd: Fix unmet dependency warning for MFD_TPS68470
-
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmcLinus Torvalds authored
Pull MMC host fixes from Ulf Hansson: - mediatek: Fix incorrect register write for tunings - bcm2835: Fixup leakage of DMA channel on probe errors * tag 'mmc-v5.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: mmc: mediatek: fix incorrect register setting of hs400_cmd_int_delay mmc: bcm2835: Fix DMA channel leak on probe error
-
git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxLinus Torvalds authored
Pull i3c fixes from Boris Brezillon: - Fix a deadlock in the designware driver - Fix the error path in i3c_master_add_i3c_dev_locked() * tag 'i3c/fixes-for-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: i3c: master: dw: fix deadlock i3c: fix missing detach if failed to retrieve i3c dev
-
Linus Torvalds authored
In commit 170d13ca ("x86: re-introduce non-generic memcpy_{to,from}io") I made our copy from IO space use a separate copy routine rather than rely on the generic memcpy. I did that because our generic memory copy isn't actually well-defined when it comes to internal access ordering or alignment, and will in fact depend on various CPUID flags. In particular, the default memcpy() for a modern Intel CPU will generally be just a "rep movsb", which works reasonably well for medium-sized memory copies of regular RAM, since the CPU will turn it into fairly optimized microcode. However, for non-cached memory and IO, "rep movs" ends up being horrendously slow and will just do the architectural "one byte at a time" accesses implied by the movsb. At the other end of the spectrum, if you _don't_ end up using the "rep movsb" code, you'd likely fall back to the software copy, which does overlapping accesses for the tail, and may copy things backwards. Again, for regular memory that's fine, for IO memory not so much. The thinking was that clearly nobody really cared (because things worked), but some people had seen horrible performance due to the byte accesses, so let's just revert back to our long ago version that dod "rep movsl" for the bulk of the copy, and then fixed up the potentially last few bytes of the tail with "movsw/b". Interestingly (and perhaps not entirely surprisingly), while that was our original memory copy implementation, and had been used before for IO, in the meantime many new users of memcpy_*io() had come about. And while the access patterns for the memory copy weren't well-defined (so arguably _any_ access pattern should work), in practice the "rep movsb" case had been very common for the last several years. In particular Jarkko Sakkinen reported that the memcpy_*io() change resuled in weird errors from his Geminilake NUC TPM module. And it turns out that the TPM TCG accesses according to spec require that the accesses be (a) done strictly sequentially (b) be naturally aligned otherwise the TPM chip will abort the PCI transaction. And, in fact, the tpm_crb.c driver did this: memcpy_fromio(buf, priv->rsp, 6); ... memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6); which really should never have worked in the first place, but back before commit 170d13ca it *happened* to work, because the memcpy_fromio() would be expanded to a regular memcpy, and (a) gcc would expand the first memcpy in-line, and turn it into a 4-byte and a 2-byte read, and they happened to be in the right order, and the alignment was right. (b) gcc would call "memcpy()" for the second one, and the machines that had this TPM chip also apparently ended up always having ERMS ("Enhanced REP MOVSB/STOSB instructions"), so we'd use the "rep movbs" for that copy. In other words, basically by pure luck, the code happened to use the right access sizes in the (two different!) memcpy() implementations to make it all work. But after commit 170d13ca, both of the memcpy_fromio() calls resulted in a call to the routine with the consistent memory accesses, and in both cases it started out transferring with 4-byte accesses. Which worked for the first copy, but resulted in the second copy doing a 32-bit read at an address that was only 2-byte aligned. Jarkko is actually fixing the fragile code in the TPM driver, but since this is an excellent example of why we absolutely must not use a generic memcpy for IO accesses, _and_ an IO-specific one really should strive to align the IO accesses, let's do exactly that. Side note: Jarkko also noted that the driver had been used on ARM platforms, and had worked. That was because on 32-bit ARM, memcpy_*io() ends up always doing byte accesses, and on 64-bit ARM it first does byte accesses to align to 8-byte boundaries, and then does 8-byte accesses for the bulk. So ARM actually worked by design, and the x86 case worked by pure luck. We *might* want to make x86-64 do the 8-byte case too. That should be a pretty straightforward extension, but let's do one thing at a time. And generally MMIO accesses aren't really all that performance-critical, as shown by the fact that for a long time we just did them a byte at a time, and very few people ever noticed. Reported-and-tested-by:
Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Tested-by:
Jerry Snitselaar <jsnitsel@redhat.com> Cc: David Laight <David.Laight@aculab.com> Fixes: 170d13ca ("x86: re-introduce non-generic memcpy_{to,from}io") Signed-off-by:
-
Rafael J. Wysocki authored
* acpi-misc: platform/x86: Fix unmet dependency warning for SAMSUNG_Q10 platform/x86: Fix unmet dependency warning for ACPI_CMPC
-
Rafael J. Wysocki authored
* pm-cpuidle-fixes: cpuidle: poll_state: Fix default time limit
-
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linuxLinus Torvalds authored
Pull clk fixes from Stephen Boyd: "Mostly driver fixes, but there's a core framework fix in here too: - Revert the commits that introduce clk management for the SP clk on MMP2 SoCs (used for OLPC). Turns out it wasn't a good idea and there isn't any need to manage this clk, it just causes more headaches. - A performance regression that went unnoticed for many years where we would traverse the entire clk tree looking for a clk by name when we already have the pointer to said clk that we're looking for - A parent linkage fix for the qcom SDM845 clk driver - An i.MX clk driver rate miscalculation fix where order of operations were messed up - One error handling fix from the static checkers" * tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: clk: qcom: gcc: Use active only source for CPUSS clocks clk: ti: Fix error handling in ti_clk_parse_divider_data() clk: imx: Fix fractional clock set rate computation clk: Remove global clk traversal on fetch parent index Revert "dt-bindings: marvell,mmp2: Add clock id for the SP clock" Revert "clk: mmp2: add SP clock" Revert "Input: olpc_apsp - enable the SP clock" -
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds authored
Pull crypto fix from Herbert Xu: "This fixes a bug in cavium/nitrox where the callback is invoked prior to the DMA unmap" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: cavium/nitrox - Invoke callback after DMA unmap
-
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pciLinus Torvalds authored
Pull PCI fixes from Bjorn Helgaas: - Revert armada8k GPIO reset change that broke Macchiatobin booting (Baruch Siach) - Use actual size config reads on ARM cns3xxx (Koen Vandeputte) - Fix ARM cns3xxx config write alignment issue (Koen Vandeputte) - Fix imx6 PHY device link error checking (Leonard Crestez) - Fix imx6 probe failure on chips without separate PCI power domain (Leonard Crestez) * tag 'pci-v5.0-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: Revert "PCI: armada8k: Add support for gpio controlled reset signal" ARM: cns3xxx: Use actual size reads for PCIe ARM: cns3xxx: Fix writing to wrong PCI config registers after alignment PCI: imx: Fix checking pd_pcie_phy device link addition PCI: imx: Fix probe failure without power domain
-
- 31 Jan, 2019 9 commits
-
-
Baruch Siach authored
Revert commit 3d71746c ("PCI: armada8k: Add support for gpio controlled reset signal"). That commit breaks boot on Macchiatobin board when a Mellanox NIC is present in the PCIe slot. It turns out that full reset cycle requires first comphy serdes initialization. Reset signal toggle without comphy initialization makes access to PCI configuration registers stall indefinitely. U-Boot toggles the Macchiatobin PCIe reset line already at boot, after initializing the comphy serdes. So while commit 3d71746c ("PCI: armada8k: Add support for gpio controlled reset signal") enables PCIe on platforms that U-Boot does not touch the reset line (like Clearfog GT-8K), it breaks PCIe (and boot) on the Macchiatobin board. Revert commit 3d71746c ("PCI: armada8k: Add support for gpio controlled reset signal") entirely to fix the Macchiatobin regression. Reported-by:
Sven Auhagen <sven.auhagen@voleatech.de> Signed-off-by:
Baruch Siach <baruch@tkos.co.il> Signed-off-by:
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
-
Koen Vandeputte authored
commit 802b7c06 ("ARM: cns3xxx: Convert PCI to use generic config accessors") reimplemented cns3xxx_pci_read_config() using pci_generic_config_read32(), which preserved the property of only doing 32-bit reads. It also replaced cns3xxx_pci_write_config() with pci_generic_config_write(), so it changed writes from always being 32 bits to being the actual size, which works just fine. Given that: - The documentation does not mention that only 32 bit access is allowed. - Writes are already executed using the actual size - Extensive testing shows that 8b, 16b and 32b reads work as intended Allow read access of any size by replacing pci_generic_config_read32() with the pci_generic_config_read() accessors. Fixes: 802b7c06 ("ARM: cns3xxx: Convert PCI to use generic config accessors") Suggested-by:
Bjorn Helgaas <bhelgaas@google.com> Signed-off-by:
Koen Vandeputte <koen.vandeputte@ncentric.com> [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by:
Krzysztof Halasa <khalasa@piap.pl> Acked-by:
Arnd Bergmann <arnd@arndb.de> CC: Krzysztof Halasa <khalasa@piap.pl> CC: Olof Johansson <olof@lixom.net> CC: Robin Leblon <robin.leblon@ncentric.com> CC: Rob Herring <robh@kernel.org> CC: Russell King <linux@armlinux.org.uk> CC: Tim Harvey <tharvey@gateworks.com>
-
Koen Vandeputte authored
Originally, cns3xxx used its own functions for mapping, reading and writing config registers. Commit 802b7c06 ("ARM: cns3xxx: Convert PCI to use generic config accessors") removed the internal PCI config write function in favor of the generic one: cns3xxx_pci_write_config() --> pci_generic_config_write() cns3xxx_pci_write_config() expected aligned addresses, being produced by cns3xxx_pci_map_bus() while the generic one pci_generic_config_write() actually expects the real address as both the function and hardware are capable of byte-aligned writes. This currently leads to pci_generic_config_write() writing to the wrong registers. For instance, upon ath9k module loading: - driver ath9k gets loaded - The driver wants to write value 0xA8 to register PCI_LATENCY_TIMER, located at 0x0D - cns3xxx_pci_map_bus() aligns the address to 0x0C - pci_generic_config_write() effectively writes 0xA8 into register 0x0C (CACHE_LINE_SIZE) Fix the bug by removing the alignment in the cns3xxx mapping function. Fixes: 802b7c06 ("ARM: cns3xxx: Convert PCI to use generic config accessors") Signed-off-by:
Tim Harvey <tharvey@gateworks.com> Acked-by:
-
Leonard Crestez authored
The check on the device_link_add() return value is wrong; this leads to erroneous code execution, so fix it. Fixes: 3f7cceea ("PCI: imx: Add multi-pd support") Signed-off-by:
Leonard Crestez <leonard.crestez@nxp.com> [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by:
-
Leonard Crestez authored
On chips without a separate power domain for PCI (such as 6q/6qp) the imx6_pcie_attach_pd() function incorrectly returns an error. Fix by returning 0 if dev_pm_domain_attach_by_name() does not find anything. Fixes: 3f7cceea ("PCI: imx: Add multi-pd support") Reported-by:
Lukas F.Hartmann <lukas@mntmn.com> Signed-off-by:
-
Andreas Gruenbacher authored
This reverts commit 2d29f6b9. It turns out that the fix can lead to a ~20 percent performance regression in initial writes to the page cache according to iozone. Let's revert this for now to have more time for a proper fix. Cc: stable@vger.kernel.org # v3.13+ Signed-off-by:
Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by:
Bob Peterson <rpeterso@redhat.com> Signed-off-by:
-
Linus Torvalds authored
Merge tag 'linux-kselftest-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kselftest fixes from Shuah Khan: "This consists of run-time fixes to cpu-hotplug, and seccomp tests, compile fixes to ir, net, and timers Makefiles" * tag 'linux-kselftest-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: selftests: timers: use LDLIBS instead of LDFLAGS selftests: net: use LDLIBS instead of LDFLAGS selftests/seccomp: Enhance per-arch ptrace syscall skip tests selftests: Use lirc.h from kernel tree, not from system selftests: cpu-hotplug: fix case where CPUs offline > CPUs present
-
git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds authored
Pull NFS client fixes from Anna Schumaker: "This addresses two bugs, one in the error code handling of nfs_page_async_flush() and one to fix a potential NULL pointer dereference in nfs_parse_devname(). Stable bugfix: - Fix up return value on fatal errors in nfs_page_async_flush() Other bugfix: - Fix NULL pointer dereference of dev_name" * tag 'nfs-for-5.0-3' of git://git.linux-nfs.org/projects/anna/linux-nfs: NFS: Fix up return value on fatal errors in nfs_page_async_flush() nfs: Fix NULL pointer dereference of dev_name
-
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/soundLinus Torvalds authored
Pull sound fixes from Takashi Iwai: "Only three fixes. The fix for Realtek HD-audio looks lengthy, but it's just a code shuffling, and the actual changes are fairly small. The rest are a PCM core fix for a long-standing bug that was recently scratched by syzkaller, and a trivial USB-audio quirk for DSD support" * tag 'sound-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ALSA: hda/realtek - Fixed hp_pin no value ALSA: pcm: Fix tight loop of OSS capture stream ALSA: usb-audio: Add Opus #3 to quirks for native DSD support
-
- 30 Jan, 2019 4 commits
-
-
Doug Smythies authored
The default time is declared in units of microsecnds, but is used as nanoseconds, resulting in significant accounting errors for idle state 0 time when all idle states deeper than 0 are disabled. Under these unusual conditions, we don't really care about the poll time limit anyhow. Fixes: 800fb34a ("cpuidle: poll_state: Disregard disable idle states") Signed-off-by:
Doug Smythies <dsmythies@telus.net> Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com>
-
Vincent Guittot authored
A deadlock has been seen when swicthing clocksources which use PM-runtime. The call path is: change_clocksource ... write_seqcount_begin ... timekeeping_update ... sh_cmt_clocksource_enable ... rpm_resume pm_runtime_mark_last_busy ktime_get do read_seqcount_begin while read_seqcount_retry .... write_seqcount_end Although we should be safe because we haven't yet changed the clocksource at that time, we can't do that because of seqcount protection. Use ktime_get_mono_fast_ns() instead which is lock safe for such cases. With ktime_get_mono_fast_ns, the timestamp is not guaranteed to be monotonic across an update and as a result can goes backward. According to update_fast_timekeeper() description: "In the worst case, this can result is a slightly wrong timestamp (a few nanoseconds)". For PM-runtime autosuspend, this means only that the suspend decision may be slightly suboptimal. Fixes: 8234f673 ("PM-runtime: Switch autosuspend over to using hrtimers") Reported-by:Biju Das <biju.das@bp.renesas.com> Signed-off-by:
Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by:
Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by:
-
Waiman Long authored
The current dentry number tracking code doesn't distinguish between positive & negative dentries. It just reports the total number of dentries in the LRU lists. As excessive number of negative dentries can have an impact on system performance, it will be wise to track the number of positive and negative dentries separately. This patch adds tracking for the total number of negative dentries in the system LRU lists and reports it in the 5th field in the /proc/sys/fs/dentry-state file. The number, however, does not include negative dentries that are in flight but not in the LRU yet as well as those in the shrinker lists which are on the way out anyway. The number of positive dentries in the LRU lists can be roughly found by subtracting the number of negative dentries from the unused count. Matthew Wilcox had confirmed that since the introduction of the dentry_stat structure in 2.1.60, the dummy array was there, probably for future extension. They were not replacements of pre-existing fields. So no sane applications that read the value of /proc/sys/fs/dentry-state will do dummy thing if the last 2 fields of the sysctl parameter are not zero. IOW, it will be safe to use one of the dummy array entry for negative dentry count. Signed-off-by:
Waiman Long <longman@redhat.com> Signed-off-by:
-
Waiman Long authored
The list_lru structure is essentially just a pointer to a table of per-node LRU lists. Even if CONFIG_MEMCG_KMEM is defined, the list field is just used for LRU list registration and shrinker_id is set at initialization. Those fields won't need to be touched that often. So there is no point to make the list_lru structures to sit in their own cachelines. Signed-off-by:
Dave Chinner <dchinner@redhat.com> Signed-off-by:
-
