- 30 May, 2018 40 commits
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Anders Roxell authored
[ Upstream commit 9a606f8d ] The memfd test requires to insert the fuse module (CONFIG_FUSE_FS). Signed-off-by:
Anders Roxell <anders.roxell@linaro.org> Signed-off-by:
Daniel Díaz <daniel.diaz@linaro.org> Signed-off-by:
Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by:
Sasha Levin <alexander.levin@microsoft.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Naresh Kamboju authored
[ Upstream commit 9a379e77 ] pstore_tests and pstore_post_reboot_tests need CONFIG_PSTORE_RAM=m Signed-off-by:
Naresh Kamboju <naresh.kamboju@linaro.org> Acked-by:
Kees Cook <keescook@chromium.org> Signed-off-by:
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Dong Bo authored
[ Upstream commit 0d3e45bc ] This fixs the following comile warnings with ATA_DEBUG enabled, which detected by Linaro GCC 5.2-2015.11: drivers/ata/libata-scsi.c: In function 'ata_scsi_dump_cdb': ./include/linux/kern_levels.h:5:18: warning: format '%d' expects argument of type 'int', but argument 6 has type 'u64 {aka long long unsigned int}' [-Wformat=] tj: Patch hand-applied and description trimmed. Signed-off-by:
Dong Bo <dongbo4@huawei.com> Signed-off-by:
Tejun Heo <tj@kernel.org> Signed-off-by:
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Jason Wang authored
[ Upstream commit 54e02162 ] Switch to use dividing to prevent integer overflow when size is too big to calculate allocation size properly. Reported-by:
Eric Biggers <ebiggers3@gmail.com> Fixes: 6e6e41c3 ("ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE") Signed-off-by:
Jason Wang <jasowang@redhat.com> Acked-by:
Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
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Ulf Magnusson authored
[ Upstream commit 827cc2fa ] 'default N' should be 'default n', though they happen to have the same effect here, due to undefined symbols (N in this case) evaluating to n in a tristate sense. Remove the default from ARC_EMUL_UNALIGNED instead of changing it. bool and tristate symbols implicitly default to n. Discovered with the https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_ulfalizer_Kconfiglib_blob_master_examples_list-5Fundefined.py&d=DwIBAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=c14YS-cH-kdhTOW89KozFhBtBJgs1zXscZojEZQ0THs&m=WxxD8ozR7QQUVzNCBksiznaisBGO_crN7PBOvAoju8s&s=1LmxsNqxwT-7wcInVpZ6Z1J27duZKSoyKxHIJclXU_M&e= script. Signed-off-by:
Ulf Magnusson <ulfalizer@gmail.com> Signed-off-by:
Vineet Gupta <vgupta@synopsys.com> Signed-off-by:
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Mark Salter authored
[ Upstream commit b6dd4d83 ] The pr_debug() in gic-v3 gic_send_sgi() can trigger a circular locking warning: GICv3: CPU10: ICC_SGI1R_EL1 5000400 ====================================================== WARNING: possible circular locking dependency detected 4.15.0+ #1 Tainted: G W ------------------------------------------------------ dynamic_debug01/1873 is trying to acquire lock: ((console_sem).lock){-...}, at: [<0000000099c891ec>] down_trylock+0x20/0x4c but task is already holding lock: (&rq->lock){-.-.}, at: [<00000000842e1587>] __task_rq_lock+0x54/0xdc which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->lock){-.-.}: __lock_acquire+0x3b4/0x6e0 lock_acquire+0xf4/0x2a8 _raw_spin_lock+0x4c/0x60 task_fork_fair+0x3c/0x148 sched_fork+0x10c/0x214 copy_process.isra.32.part.33+0x4e8/0x14f0 _do_fork+0xe8/0x78c kernel_thread+0x48/0x54 rest_init+0x34/0x2a4 start_kernel+0x45c/0x488 -> #1 (&p->pi_lock){-.-.}: __lock_acquire+0x3b4/0x6e0 lock_acquire+0xf4/0x2a8 _raw_spin_lock_irqsave+0x58/0x70 try_to_wake_up+0x48/0x600 wake_up_process+0x28/0x34 __up.isra.0+0x60/0x6c up+0x60/0x68 __up_console_sem+0x4c/0x7c console_unlock+0x328/0x634 vprintk_emit+0x25c/0x390 dev_vprintk_emit+0xc4/0x1fc dev_printk_emit+0x88/0xa8 __dev_printk+0x58/0x9c _dev_info+0x84/0xa8 usb_new_device+0x100/0x474 hub_port_connect+0x280/0x92c hub_event+0x740/0xa84 process_one_work+0x240/0x70c worker_thread+0x60/0x400 kthread+0x110/0x13c ret_from_fork+0x10/0x18 -> #0 ((console_sem).lock){-...}: validate_chain.isra.34+0x6e4/0xa20 __lock_acquire+0x3b4/0x6e0 lock_acquire+0xf4/0x2a8 _raw_spin_lock_irqsave+0x58/0x70 down_trylock+0x20/0x4c __down_trylock_console_sem+0x3c/0x9c console_trylock+0x20/0xb0 vprintk_emit+0x254/0x390 vprintk_default+0x58/0x90 vprintk_func+0xbc/0x164 printk+0x80/0xa0 __dynamic_pr_debug+0x84/0xac gic_raise_softirq+0x184/0x18c smp_cross_call+0xac/0x218 smp_send_reschedule+0x3c/0x48 resched_curr+0x60/0x9c check_preempt_curr+0x70/0xdc wake_up_new_task+0x310/0x470 _do_fork+0x188/0x78c SyS_clone+0x44/0x50 __sys_trace_return+0x0/0x4 other info that might help us debug this: Chain exists of: (console_sem).lock --> &p->pi_lock --> &rq->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->lock); lock(&p->pi_lock); lock(&rq->lock); lock((console_sem).lock); *** DEADLOCK *** 2 locks held by dynamic_debug01/1873: #0: (&p->pi_lock){-.-.}, at: [<000000001366df53>] wake_up_new_task+0x40/0x470 #1: (&rq->lock){-.-.}, at: [<00000000842e1587>] __task_rq_lock+0x54/0xdc stack backtrace: CPU: 10 PID: 1873 Comm: dynamic_debug01 Tainted: G W 4.15.0+ #1 Hardware name: GIGABYTE R120-T34-00/MT30-GS2-00, BIOS T48 10/02/2017 Call trace: dump_backtrace+0x0/0x188 show_stack+0x24/0x2c dump_stack+0xa4/0xe0 print_circular_bug.isra.31+0x29c/0x2b8 check_prev_add.constprop.39+0x6c8/0x6dc validate_chain.isra.34+0x6e4/0xa20 __lock_acquire+0x3b4/0x6e0 lock_acquire+0xf4/0x2a8 _raw_spin_lock_irqsave+0x58/0x70 down_trylock+0x20/0x4c __down_trylock_console_sem+0x3c/0x9c console_trylock+0x20/0xb0 vprintk_emit+0x254/0x390 vprintk_default+0x58/0x90 vprintk_func+0xbc/0x164 printk+0x80/0xa0 __dynamic_pr_debug+0x84/0xac gic_raise_softirq+0x184/0x18c smp_cross_call+0xac/0x218 smp_send_reschedule+0x3c/0x48 resched_curr+0x60/0x9c check_preempt_curr+0x70/0xdc wake_up_new_task+0x310/0x470 _do_fork+0x188/0x78c SyS_clone+0x44/0x50 __sys_trace_return+0x0/0x4 GICv3: CPU0: ICC_SGI1R_EL1 12000 This could be fixed with printk_deferred() but that might lessen its usefulness for debugging. So change it to pr_devel to keep it out of production kernels. Developers working on gic-v3 can enable it as needed in their kernels. Signed-off-by:
Mark Salter <msalter@redhat.com> Signed-off-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
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Michael Kelley authored
[ Upstream commit d207af2e ] for_each_cpu_wrap() was originally added in the #else half of a large "#if NR_CPUS == 1" statement, but was omitted in the #if half. This patch adds the missing #if half to prevent compile errors when NR_CPUS is 1. Reported-by:
kbuild test robot <fengguang.wu@intel.com> Signed-off-by:
Michael Kelley <mhkelley@outlook.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kys@microsoft.com Cc: martin.petersen@oracle.com Cc: mikelley@microsoft.com Fixes: c743f0a5 ("sched/fair, cpumask: Export for_each_cpu_wrap()") Link: http://lkml.kernel.org/r/SN6PR1901MB2045F087F59450507D4FCC17CBF50@SN6PR1901MB2045.namprd19.prod.outlook.comSigned-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Stephen Boyd authored
[ Upstream commit 95a25625 ] On some platforms there's an ITS available but it's not enabled because reading or writing the registers is denied by the firmware. In fact, reading or writing them will cause the system to reset. We could remove the node from DT in such a case, but it's better to skip nodes that are marked as "disabled" in DT so that we can describe the hardware that exists and use the status property to indicate how the firmware has configured things. Cc: Stuart Yoder <stuyoder@gmail.com> Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Rajendra Nayak <rnayak@codeaurora.org> Signed-off-by:
Stephen Boyd <sboyd@codeaurora.org> Signed-off-by:
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Will Deacon authored
[ Upstream commit 11dc1322 ] When queuing on the qspinlock, the count field for the current CPU's head node is incremented. This needn't be atomic because locking in e.g. IRQ context is balanced and so an IRQ will return with node->count as it found it. However, the compiler could in theory reorder the initialisation of node[idx] before the increment of the head node->count, causing an IRQ to overwrite the initialised node and potentially corrupt the lock state. Avoid the potential for this harmful compiler reordering by placing a barrier() between the increment of the head node->count and the subsequent node initialisation. Signed-off-by:
Will Deacon <will.deacon@arm.com> Acked-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1518528177-19169-3-git-send-email-will.deacon@arm.comSigned-off-by:
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Jia Zhang authored
[ Upstream commit 595dd46e ] Commit: df04abfd ("fs/proc/kcore.c: Add bounce buffer for ktext data") ... introduced a bounce buffer to work around CONFIG_HARDENED_USERCOPY=y. However, accessing the vsyscall user page will cause an SMAP fault. Replace memcpy() with copy_from_user() to fix this bug works, but adding a common way to handle this sort of user page may be useful for future. Currently, only vsyscall page requires KCORE_USER. Signed-off-by:
Jia Zhang <zhang.jia@linux.alibaba.com> Reviewed-by:
Jiri Olsa <jolsa@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: jolsa@redhat.com Link: http://lkml.kernel.org/r/1518446694-21124-2-git-send-email-zhang.jia@linux.alibaba.comSigned-off-by:
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Daniel Borkmann authored
[ Upstream commit 941ff6f1 ] Fix two issues in the reuseport_bpf selftests that were reported by Linaro CI: [...] + ./reuseport_bpf ---- IPv4 UDP ---- Testing EBPF mod 10... Reprograming, testing mod 5... ./reuseport_bpf: ebpf error. log: 0: (bf) r6 = r1 1: (20) r0 = *(u32 *)skb[0] 2: (97) r0 %= 10 3: (95) exit processed 4 insns : Operation not permitted + echo FAIL [...] ---- IPv4 TCP ---- Testing EBPF mod 10... ./reuseport_bpf: failed to bind send socket: Address already in use + echo FAIL [...] For the former adjust rlimit since this was the cause of failure for loading the BPF prog, and for the latter add SO_REUSEADDR. Reported-by:
Daniel Borkmann <daniel@iogearbox.net> Signed-off-by:
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Jesper Dangaard Brouer authored
[ Upstream commit e3d91b0c ] V3: More generic skipping of relo-section (suggested by Daniel) If clang >= 4.0.1 is missing the option '-target bpf', it will cause llc/llvm to create two ELF sections for "Exception Frames", with section names '.eh_frame' and '.rel.eh_frame'. The BPF ELF loader library libbpf fails when loading files with these sections. The other in-kernel BPF ELF loader in samples/bpf/bpf_load.c, handle this gracefully. And iproute2 loader also seems to work with these "eh" sections. The issue in libbpf is caused by bpf_object__elf_collect() skipping some sections, and later when performing relocation it will be pointing to a skipped section, as these sections cannot be found by bpf_object__find_prog_by_idx() in bpf_object__collect_reloc(). This is a general issue that also occurs for other sections, like debug sections which are also skipped and can have relo section. As suggested by Daniel. To avoid keeping state about all skipped sections, instead perform a direct qlookup in the ELF object. Lookup the section that the relo-section points to and check if it contains executable machine instructions (denoted by the sh_flags SHF_EXECINSTR). Use this check to also skip irrelevant relo-sections. Note, for samples/bpf/ the '-target bpf' parameter to clang cannot be used due to incompatibility with asm embedded headers, that some of the samples include. This is explained in more details by Yonghong Song in bpf_devel_QA. Signed-off-by:
Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by:
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Tang Junhui authored
[ Upstream commit 7f4fc93d ] I attach a back-end device to a cache set, and the cache set is not registered yet, this back-end device did not attach successfully, and no error returned: [root]# echo 87859280-fec6-4bcc-20df7ca8f86b > /sys/block/sde/bcache/attach [root]# In sysfs_attach(), the return value "v" is initialized to "size" in the beginning, and if no cache set exist in bch_cache_sets, the "v" value would not change any more, and return to sysfs, sysfs regard it as success since the "size" is a positive number. This patch fixes this issue by assigning "v" with "-ENOENT" in the initialization. Signed-off-by:
Tang Junhui <tang.junhui@zte.com.cn> Reviewed-by:
Michael Lyle <mlyle@lyle.org> Signed-off-by:
Jens Axboe <axboe@kernel.dk> Signed-off-by:
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Tang Junhui authored
[ Upstream commit 73ac105b ] back-end device sdm has already attached a cache_set with ID f67ebe1f-f8bc-4d73-bfe5-9dc88607f119, then try to attach with another cache set, and it returns with an error: [root]# cd /sys/block/sdm/bcache [root]# echo 5ccd0a63-148e-48b8-afa2-aca9cbd6279f > attach -bash: echo: write error: Invalid argument After that, execute a command to modify the label of bcache device: [root]# echo data_disk1 > label Then we reboot the system, when the system power on, the back-end device can not attach to cache_set, a messages show in the log: Feb 5 12:05:52 ceph152 kernel: [922385.508498] bcache: bch_cached_dev_attach() couldn't find uuid for sdm in set In sysfs_attach(), dc->sb.set_uuid was assigned to the value which input through sysfs, no matter whether it is success or not in bch_cached_dev_attach(). For example, If the back-end device has already attached to an cache set, bch_cached_dev_attach() would fail, but dc->sb.set_uuid was changed. Then modify the label of bcache device, it will call bch_write_bdev_super(), which would write the dc->sb.set_uuid to the super block, so we record a wrong cache set ID in the super block, after the system reboot, the cache set couldn't find the uuid of the back-end device, so the bcache device couldn't exist and use any more. In this patch, we don't assigned cache set ID to dc->sb.set_uuid in sysfs_attach() directly, but input it into bch_cached_dev_attach(), and assigned dc->sb.set_uuid to the cache set ID after the back-end device attached to the cache set successful. Signed-off-by:
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Tang Junhui authored
[ Upstream commit 682811b3 ] After long time running of random small IO writing, I reboot the machine, and after the machine power on, I found bcache got stuck, the stack is: [root@ceph153 ~]# cat /proc/2510/task/*/stack [<ffffffffa06b2455>] closure_sync+0x25/0x90 [bcache] [<ffffffffa06b6be8>] bch_journal+0x118/0x2b0 [bcache] [<ffffffffa06b6dc7>] bch_journal_meta+0x47/0x70 [bcache] [<ffffffffa06be8f7>] bch_prio_write+0x237/0x340 [bcache] [<ffffffffa06a8018>] bch_allocator_thread+0x3c8/0x3d0 [bcache] [<ffffffff810a631f>] kthread+0xcf/0xe0 [<ffffffff8164c318>] ret_from_fork+0x58/0x90 [<ffffffffffffffff>] 0xffffffffffffffff [root@ceph153 ~]# cat /proc/2038/task/*/stack [<ffffffffa06b1abd>] __bch_btree_map_nodes+0x12d/0x150 [bcache] [<ffffffffa06b1bd1>] bch_btree_insert+0xf1/0x170 [bcache] [<ffffffffa06b637f>] bch_journal_replay+0x13f/0x230 [bcache] [<ffffffffa06c75fe>] run_cache_set+0x79a/0x7c2 [bcache] [<ffffffffa06c0cf8>] register_bcache+0xd48/0x1310 [bcache] [<ffffffff812f702f>] kobj_attr_store+0xf/0x20 [<ffffffff8125b216>] sysfs_write_file+0xc6/0x140 [<ffffffff811dfbfd>] vfs_write+0xbd/0x1e0 [<ffffffff811e069f>] SyS_write+0x7f/0xe0 [<ffffffff8164c3c9>] system_call_fastpath+0x16/0x1 The stack shows the register thread and allocator thread were getting stuck when registering cache device. I reboot the machine several times, the issue always exsit in this machine. I debug the code, and found the call trace as bellow: register_bcache() ==>run_cache_set() ==>bch_journal_replay() ==>bch_btree_insert() ==>__bch_btree_map_nodes() ==>btree_insert_fn() ==>btree_split() //node need split ==>btree_check_reserve() In btree_check_reserve(), It will check if there is enough buckets of RESERVE_BTREE type, since allocator thread did not work yet, so no buckets of RESERVE_BTREE type allocated, so the register thread waits on c->btree_cache_wait, and goes to sleep. Then the allocator thread initialized, the call trace is bellow: bch_allocator_thread() ==>bch_prio_write() ==>bch_journal_meta() ==>bch_journal() ==>journal_wait_for_write() In journal_wait_for_write(), It will check if journal is full by journal_full(), but the long time random small IO writing causes the exhaustion of journal buckets(journal.blocks_free=0), In order to release the journal buckets, the allocator calls btree_flush_write() to flush keys to btree nodes, and waits on c->journal.wait until btree nodes writing over or there has already some journal buckets space, then the allocator thread goes to sleep. but in btree_flush_write(), since bch_journal_replay() is not finished, so no btree nodes have journal (condition "if (btree_current_write(b)->journal)" never satisfied), so we got no btree node to flush, no journal bucket released, and allocator sleep all the times. Through the above analysis, we can see that: 1) Register thread wait for allocator thread to allocate buckets of RESERVE_BTREE type; 2) Alloctor thread wait for register thread to replay journal, so it can flush btree nodes and get journal bucket. then they are all got stuck by waiting for each other. Hua Rui provided a patch for me, by allocating some buckets of RESERVE_BTREE type in advance, so the register thread can get bucket when btree node splitting and no need to waiting for the allocator thread. I tested it, it has effect, and register thread run a step forward, but finally are still got stuck, the reason is only 8 bucket of RESERVE_BTREE type were allocated, and in bch_journal_replay(), after 2 btree nodes splitting, only 4 bucket of RESERVE_BTREE type left, then btree_check_reserve() is not satisfied anymore, so it goes to sleep again, and in the same time, alloctor thread did not flush enough btree nodes to release a journal bucket, so they all got stuck again. So we need to allocate more buckets of RESERVE_BTREE type in advance, but how much is enough? By experience and test, I think it should be as much as journal buckets. Then I modify the code as this patch, and test in the machine, and it works. This patch modified base on Hua Rui’s patch, and allocate more buckets of RESERVE_BTREE type in advance to avoid register thread and allocate thread going to wait for each other. [patch v2] ca->sb.njournal_buckets would be 0 in the first time after cache creation, and no journal exists, so just 8 btree buckets is OK. Signed-off-by:
Hua Rui <huarui.dev@gmail.com> Signed-off-by:
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Coly Li authored
[ Upstream commit 99361bbf ] Kernel thread routine bch_writeback_thread() has the following code block, 447 down_write(&dc->writeback_lock); 448~450 if (check conditions) { 451 up_write(&dc->writeback_lock); 452 set_current_state(TASK_INTERRUPTIBLE); 453 454 if (kthread_should_stop()) 455 return 0; 456 457 schedule(); 458 continue; 459 } If condition check is true, its task state is set to TASK_INTERRUPTIBLE and call schedule() to wait for others to wake up it. There are 2 issues in current code, 1, Task state is set to TASK_INTERRUPTIBLE after the condition checks, if another process changes the condition and call wake_up_process(dc-> writeback_thread), then at line 452 task state is set back to TASK_INTERRUPTIBLE, the writeback kernel thread will lose a chance to be waken up. 2, At line 454 if kthread_should_stop() is true, writeback kernel thread will return to kernel/kthread.c:kthread() with TASK_INTERRUPTIBLE and call do_exit(). It is not good to enter do_exit() with task state TASK_INTERRUPTIBLE, in following code path might_sleep() is called and a warning message is reported by __might_sleep(): "WARNING: do not call blocking ops when !TASK_RUNNING; state=1 set at [xxxx]". For the first issue, task state should be set before condition checks. Ineed because dc->writeback_lock is required when modifying all the conditions, calling set_current_state() inside code block where dc-> writeback_lock is hold is safe. But this is quite implicit, so I still move set_current_state() before all the condition checks. For the second issue, frankley speaking it does not hurt when kernel thread exits with TASK_INTERRUPTIBLE state, but this warning message scares users, makes them feel there might be something risky with bcache and hurt their data. Setting task state to TASK_RUNNING before returning fixes this problem. In alloc.c:allocator_wait(), there is also a similar issue, and is also fixed in this patch. Changelog: v3: merge two similar fixes into one patch v2: fix the race issue in v1 patch. v1: initial buggy fix. Signed-off-by:
Coly Li <colyli@suse.de> Reviewed-by:
Hannes Reinecke <hare@suse.de> Reviewed-by:
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Arnd Bergmann authored
[ Upstream commit ade7db99 ] This bug was fixed before, but came up again with the latest compiler in another function: fs/cifs/cifssmb.c: In function 'CIFSSMBSetEA': fs/cifs/cifssmb.c:6362:3: error: 'strncpy' offset 8 is out of the bounds [0, 4] [-Werror=array-bounds] strncpy(parm_data->list[0].name, ea_name, name_len); Let's apply the same fix that was used for the other instances. Fixes: b2a3ad9c ("cifs: silence compiler warnings showing up with gcc-4.7.0") Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
Steve French <smfrench@gmail.com> Signed-off-by:
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Alexey Dobriyan authored
[ Upstream commit ac7f1061 ] Current code does: if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2) However sscanf() is broken garbage. It silently accepts whitespace between format specifiers (did you know that?). It silently accepts valid strings which result in integer overflow. Do not use sscanf() for any even remotely reliable parsing code. OK # readlink '/proc/1/map_files/55a23af39000-55a23b05b000' /lib/systemd/systemd broken # readlink '/proc/1/map_files/ 55a23af39000-55a23b05b000' /lib/systemd/systemd broken # readlink '/proc/1/map_files/55a23af39000-55a23b05b000 ' /lib/systemd/systemd very broken # readlink '/proc/1/map_files/1000000000000000055a23af39000-55a23b05b000' /lib/systemd/systemd Andrei said: : This patch breaks criu. It was a bug in criu. And this bug is on a minor : path, which works when memfd_create() isn't available. It is a reason why : I ask to not backport this patch to stable kernels. : : In CRIU this bug can be triggered, only if this patch will be backported : to a kernel which version is lower than v3.16. Link: http://lkml.kernel.org/r/20171120212706.GA14325@avx2Signed-off-by:
Alexey Dobriyan <adobriyan@gmail.com> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Will Deacon authored
[ Upstream commit 202fb4ef ] If the spinlock "next" ticket wraps around between the initial LDR and the cmpxchg in the LSE version of spin_trylock, then we can erroneously think that we have successfuly acquired the lock because we only check whether the next ticket return by the cmpxchg is equal to the owner ticket in our updated lock word. This patch fixes the issue by performing a full 32-bit check of the lock word when trying to determine whether or not the CASA instruction updated memory. Reported-by:
Catalin Marinas <catalin.marinas@arm.com> Signed-off-by:
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Guanglei Li authored
[ Upstream commit 2c0aa086 ] Scenario: 1. Port down and do fail over 2. Ap do rds_bind syscall PID: 47039 TASK: ffff89887e2fe640 CPU: 47 COMMAND: "kworker/u:6" #0 [ffff898e35f159f0] machine_kexec at ffffffff8103abf9 #1 [ffff898e35f15a60] crash_kexec at ffffffff810b96e3 #2 [ffff898e35f15b30] oops_end at ffffffff8150f518 #3 [ffff898e35f15b60] no_context at ffffffff8104854c #4 [ffff898e35f15ba0] __bad_area_nosemaphore at ffffffff81048675 #5 [ffff898e35f15bf0] bad_area_nosemaphore at ffffffff810487d3 #6 [ffff898e35f15c00] do_page_fault at ffffffff815120b8 #7 [ffff898e35f15d10] page_fault at ffffffff8150ea95 [exception RIP: unknown or invalid address] RIP: 0000000000000000 RSP: ffff898e35f15dc8 RFLAGS: 00010282 RAX: 00000000fffffffe RBX: ffff889b77f6fc00 RCX:ffffffff81c99d88 RDX: 0000000000000000 RSI: ffff896019ee08e8 RDI:ffff889b77f6fc00 RBP: ffff898e35f15df0 R8: ffff896019ee08c8 R9:0000000000000000 R10: 0000000000000400 R11: 0000000000000000 R12:ffff896019ee08c0 R13: ffff889b77f6fe68 R14: ffffffff81c99d80 R15: ffffffffa022a1e0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #8 [ffff898e35f15dc8] cma_ndev_work_handler at ffffffffa022a228 [rdma_cm] #9 [ffff898e35f15df8] process_one_work at ffffffff8108a7c6 #10 [ffff898e35f15e58] worker_thread at ffffffff8108bda0 #11 [ffff898e35f15ee8] kthread at ffffffff81090fe6 PID: 45659 TASK: ffff880d313d2500 CPU: 31 COMMAND: "oracle_45659_ap" #0 [ffff881024ccfc98] __schedule at ffffffff8150bac4 #1 [ffff881024ccfd40] schedule at ffffffff8150c2cf #2 [ffff881024ccfd50] __mutex_lock_slowpath at ffffffff8150cee7 #3 [ffff881024ccfdc0] mutex_lock at ffffffff8150cdeb #4 [ffff881024ccfde0] rdma_destroy_id at ffffffffa022a027 [rdma_cm] #5 [ffff881024ccfe10] rds_ib_laddr_check at ffffffffa0357857 [rds_rdma] #6 [ffff881024ccfe50] rds_trans_get_preferred at ffffffffa0324c2a [rds] #7 [ffff881024ccfe80] rds_bind at ffffffffa031d690 [rds] #8 [ffff881024ccfeb0] sys_bind at ffffffff8142a670 PID: 45659 PID: 47039 rds_ib_laddr_check /* create id_priv with a null event_handler */ rdma_create_id rdma_bind_addr cma_acquire_dev /* add id_priv to cma_dev->id_list */ cma_attach_to_dev cma_ndev_work_handler /* event_hanlder is null */ id_priv->id.event_handler Signed-off-by:
Guanglei Li <guanglei.li@oracle.com> Signed-off-by:
Honglei Wang <honglei.wang@oracle.com> Reviewed-by:
Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by:
Yanjun Zhu <yanjun.zhu@oracle.com> Reviewed-by:
Leon Romanovsky <leonro@mellanox.com> Acked-by:
Santosh Shilimkar <santosh.shilimkar@oracle.com> Acked-by:
Doug Ledford <dledford@redhat.com> Signed-off-by:
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Ross Lagerwall authored
[ Upstream commit 3ac7292a ] The page given to gnttab_end_foreign_access() to free could be a compound page so use put_page() instead of free_page() since it can handle both compound and single pages correctly. This bug was discovered when migrating a Xen VM with several VIFs and CONFIG_DEBUG_VM enabled. It hits a BUG usually after fewer than 10 iterations. All netfront devices disconnect from the backend during a suspend/resume and this will call gnttab_end_foreign_access() if a netfront queue has an outstanding skb. The mismatch between calling get_page() and free_page() on a compound page causes a reference counting error which is detected when DEBUG_VM is enabled. Signed-off-by:
Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by:
Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by:
Juergen Gross <jgross@suse.com> Signed-off-by:
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Ross Lagerwall authored
[ Upstream commit f599c64f ] When a netfront device is set up it registers a netdev fairly early on, before it has set up the queues and is actually usable. A userspace tool like NetworkManager will immediately try to open it and access its state as soon as it appears. The bug can be reproduced by hotplugging VIFs until the VM runs out of grant refs. It registers the netdev but fails to set up any queues (since there are no more grant refs). In the meantime, NetworkManager opens the device and the kernel crashes trying to access the queues (of which there are none). Fix this in two ways: * For initial setup, register the netdev much later, after the queues are setup. This avoids the race entirely. * During a suspend/resume cycle, the frontend reconnects to the backend and the queues are recreated. It is possible (though highly unlikely) to race with something opening the device and accessing the queues after they have been destroyed but before they have been recreated. Extend the region covered by the rtnl semaphore to protect against this race. There is a possibility that we fail to recreate the queues so check for this in the open function. Signed-off-by:
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Matt Redfearn authored
[ Upstream commit 0cde5b44 ] When commit b27311e1 ("MIPS: TXx9: Add RBTX4939 board support") added board support for the RBTX4939, it added a call to led_classdev_register even if the LED class is built as a module. Built-in arch code cannot call module code directly like this. Commit b33b4407 ("MIPS: TXX9: use IS_ENABLED() macro") subsequently changed the inclusion of this code to a single check that CONFIG_LEDS_CLASS is either builtin or a module, but the same issue remains. This leads to MIPS allmodconfig builds failing when CONFIG_MACH_TX49XX=y is set: arch/mips/txx9/rbtx4939/setup.o: In function `rbtx4939_led_probe': setup.c:(.init.text+0xc0): undefined reference to `of_led_classdev_register' make: *** [Makefile:999: vmlinux] Error 1 Fix this by using the IS_BUILTIN() macro instead. Fixes: b27311e1 ("MIPS: TXx9: Add RBTX4939 board support") Signed-off-by:
Matt Redfearn <matt.redfearn@mips.com> Reviewed-by:
James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/18544/Signed-off-by:
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James Hogan authored
[ Upstream commit 9a9ab307 ] We now have a platform (Ranchu) in the "generic" platform which matches based on the FDT compatible string using mips_machine_is_compatible(), however that function doesn't stop at a blank struct of_device_id::compatible as that is an array in the struct, not a pointer to a string. Fix the loop completion to check the first byte of the compatible array rather than the address of the compatible array in the struct. Fixes: eed0eabd ("MIPS: generic: Introduce generic DT-based board support") Signed-off-by:
Paul Burton <paul.burton@mips.com> Reviewed-by:
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Yonghong Song authored
[ Upstream commit 09584b40 ] With CONFIG_BPF_JIT_ALWAYS_ON is defined in the config file, tools/testing/selftests/bpf/test_kmod.sh failed like below: [root@localhost bpf]# ./test_kmod.sh sysctl: setting key "net.core.bpf_jit_enable": Invalid argument [ JIT enabled:0 hardened:0 ] [ 132.175681] test_bpf: #297 BPF_MAXINSNS: Jump, gap, jump, ... FAIL to prog_create err=-524 len=4096 [ 132.458834] test_bpf: Summary: 348 PASSED, 1 FAILED, [340/340 JIT'ed] [ JIT enabled:1 hardened:0 ] [ 133.456025] test_bpf: #297 BPF_MAXINSNS: Jump, gap, jump, ... FAIL to prog_create err=-524 len=4096 [ 133.730935] test_bpf: Summary: 348 PASSED, 1 FAILED, [340/340 JIT'ed] [ JIT enabled:1 hardened:1 ] [ 134.769730] test_bpf: #297 BPF_MAXINSNS: Jump, gap, jump, ... FAIL to prog_create err=-524 len=4096 [ 135.050864] test_bpf: Summary: 348 PASSED, 1 FAILED, [340/340 JIT'ed] [ JIT enabled:1 hardened:2 ] [ 136.442882] test_bpf: #297 BPF_MAXINSNS: Jump, gap, jump, ... FAIL to prog_create err=-524 len=4096 [ 136.821810] test_bpf: Summary: 348 PASSED, 1 FAILED, [340/340 JIT'ed] [root@localhost bpf]# The test_kmod.sh load/remove test_bpf.ko multiple times with different settings for sysctl net.core.bpf_jit_{enable,harden}. The failed test #297 of test_bpf.ko is designed such that JIT always fails. Commit 290af866 (bpf: introduce BPF_JIT_ALWAYS_ON config) introduced the following tightening logic: ... if (!bpf_prog_is_dev_bound(fp->aux)) { fp = bpf_int_jit_compile(fp); #ifdef CONFIG_BPF_JIT_ALWAYS_ON if (!fp->jited) { *err = -ENOTSUPP; return fp; } #endif ... With this logic, Test #297 always gets return value -ENOTSUPP when CONFIG_BPF_JIT_ALWAYS_ON is defined, causing the test failure. This patch fixed the failure by marking Test #297 as expected failure when CONFIG_BPF_JIT_ALWAYS_ON is defined. Fixes: 290af866 (bpf: introduce BPF_JIT_ALWAYS_ON config) Signed-off-by:
Yonghong Song <yhs@fb.com> Signed-off-by:
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Hans de Goede authored
[ Upstream commit 63347db0 ] The acpi_get_bus_status wrapper for acpi_bus_get_status_handle has some code to handle certain device quirks, in some cases we also need this quirk handling for the initial _STA call. Specifically on some devices calling _STA before all _DEP dependencies are met results in errors like these: [ 0.123579] ACPI Error: No handler for Region [ECRM] (00000000ba9edc4c) [GenericSerialBus] (20170831/evregion-166) [ 0.123601] ACPI Error: Region GenericSerialBus (ID=9) has no handler (20170831/exfldio-299) [ 0.123618] ACPI Error: Method parse/execution failed \_SB.I2C1.BAT1._STA, AE_NOT_EXIST (20170831/psparse-550) acpi_get_bus_status already has code to avoid this, so by using it we also silence these errors from the initial _STA call. Note that in order for the acpi_get_bus_status handling for this to work, we initialize dep_unmet to 1 until acpi_device_dep_initialize gets called, this means that battery devices will be instantiated with an initial status of 0. This is not a problem, acpi_bus_attach will get called soon after the instantiation anyways and it will update the status as first point of order. Signed-off-by:
Hans de Goede <hdegoede@redhat.com> Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by:
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Chen Yu authored
[ Upstream commit ba1edb9a ] The following warning was triggered after resumed from S3 - if all the nonboot CPUs were put offline before suspend: [ 1840.329515] unchecked MSR access error: RDMSR from 0x771 at rIP: 0xffffffff86061e3a (native_read_msr+0xa/0x30) [ 1840.329516] Call Trace: [ 1840.329521] __rdmsr_on_cpu+0x33/0x50 [ 1840.329525] generic_exec_single+0x81/0xb0 [ 1840.329527] smp_call_function_single+0xd2/0x100 [ 1840.329530] ? acpi_ds_result_pop+0xdd/0xf2 [ 1840.329532] ? acpi_ds_create_operand+0x215/0x23c [ 1840.329534] rdmsrl_on_cpu+0x57/0x80 [ 1840.329536] ? cpumask_next+0x1b/0x20 [ 1840.329538] ? rdmsrl_on_cpu+0x57/0x80 [ 1840.329541] intel_pstate_update_perf_limits+0xf3/0x220 [ 1840.329544] ? notifier_call_chain+0x4a/0x70 [ 1840.329546] intel_pstate_set_policy+0x4e/0x150 [ 1840.329548] cpufreq_set_policy+0xcd/0x2f0 [ 1840.329550] cpufreq_update_policy+0xb2/0x130 [ 1840.329552] ? cpufreq_update_policy+0x130/0x130 [ 1840.329556] acpi_processor_ppc_has_changed+0x65/0x80 [ 1840.329558] acpi_processor_notify+0x80/0x100 [ 1840.329561] acpi_ev_notify_dispatch+0x44/0x5c [ 1840.329563] acpi_os_execute_deferred+0x14/0x20 [ 1840.329565] process_one_work+0x193/0x3c0 [ 1840.329567] worker_thread+0x35/0x3b0 [ 1840.329569] kthread+0x125/0x140 [ 1840.329571] ? process_one_work+0x3c0/0x3c0 [ 1840.329572] ? kthread_park+0x60/0x60 [ 1840.329575] ? do_syscall_64+0x67/0x180 [ 1840.329577] ret_from_fork+0x25/0x30 [ 1840.329585] unchecked MSR access error: WRMSR to 0x774 (tried to write 0x0000000000000000) at rIP: 0xffffffff86061f78 (native_write_msr+0x8/0x30) [ 1840.329586] Call Trace: [ 1840.329587] __wrmsr_on_cpu+0x37/0x40 [ 1840.329589] generic_exec_single+0x81/0xb0 [ 1840.329592] smp_call_function_single+0xd2/0x100 [ 1840.329594] ? acpi_ds_create_operand+0x215/0x23c [ 1840.329595] ? cpumask_next+0x1b/0x20 [ 1840.329597] wrmsrl_on_cpu+0x57/0x70 [ 1840.329598] ? rdmsrl_on_cpu+0x57/0x80 [ 1840.329599] ? wrmsrl_on_cpu+0x57/0x70 [ 1840.329602] intel_pstate_hwp_set+0xd3/0x150 [ 1840.329604] intel_pstate_set_policy+0x119/0x150 [ 1840.329606] cpufreq_set_policy+0xcd/0x2f0 [ 1840.329607] cpufreq_update_policy+0xb2/0x130 [ 1840.329610] ? cpufreq_update_policy+0x130/0x130 [ 1840.329613] acpi_processor_ppc_has_changed+0x65/0x80 [ 1840.329615] acpi_processor_notify+0x80/0x100 [ 1840.329617] acpi_ev_notify_dispatch+0x44/0x5c [ 1840.329619] acpi_os_execute_deferred+0x14/0x20 [ 1840.329620] process_one_work+0x193/0x3c0 [ 1840.329622] worker_thread+0x35/0x3b0 [ 1840.329624] kthread+0x125/0x140 [ 1840.329625] ? process_one_work+0x3c0/0x3c0 [ 1840.329626] ? kthread_park+0x60/0x60 [ 1840.329628] ? do_syscall_64+0x67/0x180 [ 1840.329631] ret_from_fork+0x25/0x30 This is because if there's only one online CPU, the MSR_PM_ENABLE (package wide)can not be enabled after resumed, due to intel_pstate_hwp_enable() will only be invoked on AP's online process after resumed - if there's no AP online, the HWP remains disabled after resumed (BIOS has disabled it in S3). Then if there comes a _PPC change notification which touches HWP register during this stage, the warning is triggered. Since we don't call acpi_processor_register_performance() when HWP is enabled, the pr->performance will be NULL. When this is NULL we don't need to do _PPC change notification. Reported-by:
Doug Smythies <dsmythies@telus.net> Suggested-by:
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by:
Yu Chen <yu.c.chen@intel.com> Signed-off-by:
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Jean Delvare authored
[ Upstream commit a7770ae1 ] The handling of empty DMI strings looks quite broken to me: * Strings from 1 to 7 spaces are not considered empty. * True empty DMI strings (string index set to 0) are not considered empty, and result in allocating a 0-char string. * Strings with invalid index also result in allocating a 0-char string. * Strings starting with 8 spaces are all considered empty, even if non-space characters follow (sounds like a weird thing to do, but I have actually seen occurrences of this in DMI tables before.) * Strings which are considered empty are reported as 8 spaces, instead of being actually empty. Some of these issues are the result of an off-by-one error in memcmp, the rest is incorrect by design. So let's get it square: missing strings and strings made of only spaces, regardless of their length, should be treated as empty and no memory should be allocated for them. All other strings are non-empty and should be allocated. Signed-off-by:
Jean Delvare <jdelvare@suse.de> Fixes: 79da4721 ("x86: fix DMI out of memory problems") Cc: Parag Warudkar <parag.warudkar@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Arnd Bergmann authored
[ Upstream commit 328008a7 ] The declaration for swsusp_arch_resume marks it as 'asmlinkage', but the definition in x86-32 does not, and it fails to include the header with the declaration. This leads to a warning when building with link-time-optimizations: kernel/power/power.h:108:23: error: type of 'swsusp_arch_resume' does not match original declaration [-Werror=lto-type-mismatch] extern asmlinkage int swsusp_arch_resume(void); ^ arch/x86/power/hibernate_32.c:148:0: note: 'swsusp_arch_resume' was previously declared here int swsusp_arch_resume(void) This moves the declaration into a globally visible header file and fixes up both x86 definitions to match it. Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Cc: Len Brown <len.brown@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Nicolas Pitre <nico@linaro.org> Cc: linux-pm@vger.kernel.org Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Pavel Machek <pavel@ucw.cz> Cc: Bart Van Assche <bart.vanassche@wdc.com> Link: https://lkml.kernel.org/r/20180202145634.200291-2-arnd@arndb.deSigned-off-by:
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Subash Abhinov Kasiviswanathan authored
[ Upstream commit ea23d5e3 ] Failures were seen in ICMPv6 fragmentation timeout tests if they were run after the RFC2460 failure tests. Kernel was not sending out the ICMPv6 fragment reassembly time exceeded packet after the fragmentation reassembly timeout of 1 minute had elapsed. This happened because the frag queue was not released if an error in IPv6 fragmentation header was detected by RFC2460. Fixes: 83f1999c ("netfilter: ipv6: nf_defrag: Pass on packets to stack per RFC2460") Signed-off-by:
Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Signed-off-by:
Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by:
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Karol Herbst authored
[ Upstream commit fe9748b7 ] Fixes failure to compile with recent envyas as a result of the 'movw' alias being removed for v5. A bit of history: v3 only has a 16-bit sign-extended immediate mov op. In order to set the high bits, there's a separate 'sethi' op. envyas validates that the value passed to mov(imm) is between -0x8000 and 0x7fff. In order to simplify macros that load both the low and high word, a 'movw' alias was added which takes an unsigned 16-bit immediate. However the actual hardware op still sign extends. v5 has a full 32-bit immediate mov op. The v3 16-bit immediate mov op is gone (loads 0 into the dst reg). However due to a bug in envyas, the movw alias still existed, and selected the no-longer-present v3 16-bit immediate mov op. As a result usage of movw on v5 is the same as mov with a 0x0 argument. The proper fix throughout is to only ever use the 'movw' alias in combination with 'sethi'. Anything else should get the sign-extended validation to ensure that the intended value ends up in the destination register. Changes in fuc3 binaries is the result of a different encoding being selected for a mov with an 8-bit value. v2: added commit message written by Ilia, thanks for that! v3: messed up rebasing, now it should apply Signed-off-by:
Karol Herbst <kherbst@redhat.com> Signed-off-by:
Ben Skeggs <bskeggs@redhat.com> Signed-off-by:
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Alex Estrin authored
[ Upstream commit 10293610 ] On reboot SM can program port pkey table before ipoib registered its event handler, which could result in missing pkey event and leave root interface with initial pkey value from index 0. Since OPA port starts with invalid pkey in index 0, root interface will fail to initialize and stay down with no-carrier flag. For IB ipoib interface may end up with pkey different from value opensm put in pkey table idx 0, resulting in connectivity issues (different mcast groups, for example). Close the window by calling event handler after registration to make sure ipoib pkey is in sync with port pkey table. Reviewed-by:
Mike Marciniszyn <mike.marciniszyn@intel.com> Reviewed-by:
Ira Weiny <ira.weiny@intel.com> Signed-off-by:
Alex Estrin <alex.estrin@intel.com> Signed-off-by:
Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by:
Jason Gunthorpe <jgg@mellanox.com> Signed-off-by:
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Ed Swierk authored
[ Upstream commit 9382fe71 ] IPv4 and IPv6 packets may arrive with lower-layer padding that is not included in the L3 length. For example, a short IPv4 packet may have up to 6 bytes of padding following the IP payload when received on an Ethernet device with a minimum packet length of 64 bytes. Higher-layer processing functions in netfilter (e.g. nf_ip_checksum(), and help() in nf_conntrack_ftp) assume skb->len reflects the length of the L3 header and payload, rather than referring back to ip_hdr->tot_len or ipv6_hdr->payload_len, and get confused by lower-layer padding. In the normal IPv4 receive path, ip_rcv() trims the packet to ip_hdr->tot_len before invoking netfilter hooks. In the IPv6 receive path, ip6_rcv() does the same using ipv6_hdr->payload_len. Similarly in the br_netfilter receive path, br_validate_ipv4() and br_validate_ipv6() trim the packet to the L3 length before invoking netfilter hooks. Currently in the OVS conntrack receive path, ovs_ct_execute() pulls the skb to the L3 header but does not trim it to the L3 length before calling nf_conntrack_in(NF_INET_PRE_ROUTING). When nf_conntrack_proto_tcp encounters a packet with lower-layer padding, nf_ip_checksum() fails causing a "nf_ct_tcp: bad TCP checksum" log message. While extra zero bytes don't affect the checksum, the length in the IP pseudoheader does. That length is based on skb->len, and without trimming, it doesn't match the length the sender used when computing the checksum. In ovs_ct_execute(), trim the skb to the L3 length before higher-layer processing. Signed-off-by:
Ed Swierk <eswierk@skyportsystems.com> Acked-by:
Pravin B Shelar <pshelar@ovn.org> Signed-off-by:
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shidao.ytt authored
[ Upstream commit a7ab400d ] During our recent testing with fadvise(FADV_DONTNEED), we find that if given offset/length is not page-aligned, the last page will not be discarded. The tool we use is vmtouch (https://hoytech.com/vmtouch/), we map a 10KB-sized file into memory and then try to run this tool to evict the whole file mapping, but the last single page always remains staying in the memory: $./vmtouch -e test_10K Files: 1 Directories: 0 Evicted Pages: 3 (12K) Elapsed: 2.1e-05 seconds $./vmtouch test_10K Files: 1 Directories: 0 Resident Pages: 1/3 4K/12K 33.3% Elapsed: 5.5e-05 seconds However when we test with an older kernel, say 3.10, this problem is gone. So we wonder if this is a regression: $./vmtouch -e test_10K Files: 1 Directories: 0 Evicted Pages: 3 (12K) Elapsed: 8.2e-05 seconds $./vmtouch test_10K Files: 1 Directories: 0 Resident Pages: 0/3 0/12K 0% <-- partial page also discarded Elapsed: 5e-05 seconds After digging a little bit into this problem, we find it seems not a regression. Not discarding partial page is likely to be on purpose according to commit 441c228f ("mm: fadvise: document the fadvise(FADV_DONTNEED) behaviour for partial pages") written by Mel Gorman. He explained why partial pages should be preserved instead of being discarded when using fadvise(FADV_DONTNEED). However, the interesting part is that the actual code did NOT work as the same as it was described, the partial page was still discarded anyway, due to a calculation mistake of `end_index' passed to invalidate_mapping_pages(). This mistake has not been fixed until recently, that's why we fail to reproduce our problem in old kernels. The fix is done in commit 18aba41c ("mm/fadvise.c: do not discard partial pages with POSIX_FADV_DONTNEED") by Oleg Drokin. Back to the original testing, our problem becomes that there is a special case that, if the page-unaligned `endbyte' is also the end of file, it is not necessary at all to preserve the last partial page, as we all know no one else will use the rest of it. It should be safe enough if we just discard the whole page. So we add an EOF check in this patch. We also find a poosbile real world issue in mainline kernel. Assume such scenario: A userspace backup application want to backup a huge amount of small files (<4k) at once, the developer might (I guess) want to use fadvise(FADV_DONTNEED) to save memory. However, FADV_DONTNEED won't really happen since the only page mapped is a partial page, and kernel will preserve it. Our patch also fixes this problem, since we know the endbyte is EOF, so we discard it. Here is a simple reproducer to reproduce and verify each scenario we described above: test_fadvise.c ============================== #include <sys/mman.h> #include <sys/stat.h> #include <fcntl.h> #include <stdlib.h> #include <string.h> #include <stdio.h> #include <unistd.h> int main(int argc, char **argv) { int i, fd, ret, len; struct stat buf; void *addr; unsigned char *vec; char *strbuf; ssize_t pagesize = getpagesize(); ssize_t filesize; fd = open(argv[1], O_RDWR|O_CREAT, S_IRUSR|S_IWUSR); if (fd < 0) return -1; filesize = strtoul(argv[2], NULL, 10); strbuf = malloc(filesize); memset(strbuf, 42, filesize); write(fd, strbuf, filesize); free(strbuf); fsync(fd); len = (filesize + pagesize - 1) / pagesize; printf("length of pages: %d\n", len); addr = mmap(NULL, filesize, PROT_READ, MAP_SHARED, fd, 0); if (addr == MAP_FAILED) return -1; ret = posix_fadvise(fd, 0, filesize, POSIX_FADV_DONTNEED); if (ret < 0) return -1; vec = malloc(len); ret = mincore(addr, filesize, (void *)vec); if (ret < 0) return -1; for (i = 0; i < len; i++) printf("pages[%d]: %x\n", i, vec[i] & 0x1); free(vec); close(fd); return 0; } ============================== Test 1: running on kernel with commit 18aba41c reverted: [root@caspar ~]# uname -r 4.15.0-rc6.revert+ [root@caspar ~]# ./test_fadvise file1 1024 length of pages: 1 pages[0]: 0 # <-- partial page discarded [root@caspar ~]# ./test_fadvise file2 8192 length of pages: 2 pages[0]: 0 pages[1]: 0 [root@caspar ~]# ./test_fadvise file3 10240 length of pages: 3 pages[0]: 0 pages[1]: 0 pages[2]: 0 # <-- partial page discarded Test 2: running on mainline kernel: [root@caspar ~]# uname -r 4.15.0-rc6+ [root@caspar ~]# ./test_fadvise test1 1024 length of pages: 1 pages[0]: 1 # <-- partial and the only page not discarded [root@caspar ~]# ./test_fadvise test2 8192 length of pages: 2 pages[0]: 0 pages[1]: 0 [root@caspar ~]# ./test_fadvise test3 10240 length of pages: 3 pages[0]: 0 pages[1]: 0 pages[2]: 1 # <-- partial page not discarded Test 3: running on kernel with this patch: [root@caspar ~]# uname -r 4.15.0-rc6.patched+ [root@caspar ~]# ./test_fadvise test1 1024 length of pages: 1 pages[0]: 0 # <-- partial page and EOF, discarded [root@caspar ~]# ./test_fadvise test2 8192 length of pages: 2 pages[0]: 0 pages[1]: 0 [root@caspar ~]# ./test_fadvise test3 10240 length of pages: 3 pages[0]: 0 pages[1]: 0 pages[2]: 0 # <-- partial page and EOF, discarded [akpm@linux-foundation.org: tweak code comment] Link: http://lkml.kernel.org/r/5222da9ee20e1695eaabb69f631f200d6e6b8876.1515132470.git.jinli.zjl@alibaba-inc.comSigned-off-by:
shidao.ytt <shidao.ytt@alibaba-inc.com> Signed-off-by:
Caspar Zhang <jinli.zjl@alibaba-inc.com> Reviewed-by:
Oliver Yang <zhiche.yy@alibaba-inc.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by:
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Mel Gorman authored
[ Upstream commit 69d763fc ] Minchan Kim asked the following question -- what locks protects address_space destroying when race happens between inode trauncation and __isolate_lru_page? Jan Kara clarified by describing the race as follows CPU1 CPU2 truncate(inode) __isolate_lru_page() ... truncate_inode_page(mapping, page); delete_from_page_cache(page) spin_lock_irqsave(&mapping->tree_lock, flags); __delete_from_page_cache(page, NULL) page_cache_tree_delete(..) ... mapping = page_mapping(page); page->mapping = NULL; ... spin_unlock_irqrestore(&mapping->tree_lock, flags); page_cache_free_page(mapping, page) put_page(page) if (put_page_testzero(page)) -> false - inode now has no pages and can be freed including embedded address_space if (mapping && !mapping->a_ops->migratepage) - we've dereferenced mapping which is potentially already free. The race is theoretically possible but unlikely. Before the delete_from_page_cache, truncate_cleanup_page is called so the page is likely to be !PageDirty or PageWriteback which gets skipped by the only caller that checks the mappping in __isolate_lru_page. Even if the race occurs, a substantial amount of work has to happen during a tiny window with no preemption but it could potentially be done using a virtual machine to artifically slow one CPU or halt it during the critical window. This patch should eliminate the race with truncation by try-locking the page before derefencing mapping and aborting if the lock was not acquired. There was a suggestion from Huang Ying to use RCU as a side-effect to prevent mapping being freed. However, I do not like the solution as it's an unconventional means of preserving a mapping and it's not a context where rcu_read_lock is obviously protecting rcu data. Link: http://lkml.kernel.org/r/20180104102512.2qos3h5vqzeisrek@techsingularity.net Fixes: c8244935 ("mm: compaction: make isolate_lru_page() filter-aware again") Signed-off-by:
Mel Gorman <mgorman@techsingularity.net> Acked-by:
Minchan Kim <minchan@kernel.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by:
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Yang Shi authored
[ Upstream commit 3b454ad3 ] In the current design, khugepaged needs to acquire mmap_sem before scanning an mm. But in some corner cases, khugepaged may scan a process which is modifying its memory mapping, so khugepaged blocks in uninterruptible state. But the process might hold the mmap_sem for a long time when modifying a huge memory space and it may trigger the below khugepaged hung issue: INFO: task khugepaged:270 blocked for more than 120 seconds. Tainted: G E 4.9.65-006.ali3000.alios7.x86_64 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. khugepaged D 0 270 2 0x00000000 ffff883f3deae4c0 0000000000000000 ffff883f610596c0 ffff883f7d359440 ffff883f63818000 ffffc90019adfc78 ffffffff817079a5 d67e5aa8c1860a64 0000000000000246 ffff883f7d359440 ffffc90019adfc88 ffff883f610596c0 Call Trace: schedule+0x36/0x80 rwsem_down_read_failed+0xf0/0x150 call_rwsem_down_read_failed+0x18/0x30 down_read+0x20/0x40 khugepaged+0x476/0x11d0 kthread+0xe6/0x100 ret_from_fork+0x25/0x30 So it sounds pointless to just block khugepaged waiting for the semaphore so replace down_read() with down_read_trylock() to move to scan the next mm quickly instead of just blocking on the semaphore so that other processes can get more chances to install THP. Then khugepaged can come back to scan the skipped mm when it has finished the current round full_scan. And it appears that the change can improve khugepaged efficiency a little bit. Below is the test result when running LTP on a 24 cores 4GB memory 2 nodes NUMA VM: pristine w/ trylock full_scan 197 187 pages_collapsed 21 26 thp_fault_alloc 40818 44466 thp_fault_fallback 18413 16679 thp_collapse_alloc 21 150 thp_collapse_alloc_failed 14 16 thp_file_alloc 369 369 [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: tweak comment] [arnd@arndb.de: avoid uninitialized variable use] Link: http://lkml.kernel.org/r/20171215125129.2948634-1-arnd@arndb.de Link: http://lkml.kernel.org/r/1513281203-54878-1-git-send-email-yang.s@alibaba-inc.comSigned-off-by:
Yang Shi <yang.s@alibaba-inc.com> Acked-by:
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by:
Michal Hocko <mhocko@suse.com> Cc: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by:
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Nitin Gupta authored
[ Upstream commit a8e654f0 ] It's required to avoid losing dirty and accessed bits. [akpm@linux-foundation.org: add a `do' to the do-while loop] Link: http://lkml.kernel.org/r/20171213105756.69879-9-kirill.shutemov@linux.intel.comSigned-off-by:
Nitin Gupta <nitin.m.gupta@oracle.com> Signed-off-by:
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Kirill A. Shutemov authored
[ Upstream commit c58f0bb7 ] Patch series "Do not lose dirty bit on THP pages", v4. Vlastimil noted that pmdp_invalidate() is not atomic and we can lose dirty and access bits if CPU sets them after pmdp dereference, but before set_pmd_at(). The bug can lead to data loss, but the race window is tiny and I haven't seen any reports that suggested that it happens in reality. So I don't think it worth sending it to stable. Unfortunately, there's no way to address the issue in a generic way. We need to fix all architectures that support THP one-by-one. All architectures that have THP supported have to provide atomic pmdp_invalidate() that returns previous value. If generic implementation of pmdp_invalidate() is used, architecture needs to provide atomic pmdp_estabish(). pmdp_estabish() is not used out-side generic implementation of pmdp_invalidate() so far, but I think this can change in the future. This patch (of 12): This is an implementation of pmdp_establish() that is only suitable for an architecture that doesn't have hardware dirty/accessed bits. In this case we can't race with CPU which sets these bits and non-atomic approach is fine. Link: http://lkml.kernel.org/r/20171213105756.69879-2-kirill.shutemov@linux.intel.comSigned-off-by:
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Yisheng Xie authored
[ Upstream commit 0486a38b ] As in manpage of migrate_pages, the errno should be set to EINVAL when none of the node IDs specified by new_nodes are on-line and allowed by the process's current cpuset context, or none of the specified nodes contain memory. However, when test by following case: new_nodes = 0; old_nodes = 0xf; ret = migrate_pages(pid, old_nodes, new_nodes, MAX); The ret will be 0 and no errno is set. As the new_nodes is empty, we should expect EINVAL as documented. To fix the case like above, this patch check whether target nodes AND current task_nodes is empty, and then check whether AND node_states[N_MEMORY] is empty. Link: http://lkml.kernel.org/r/1510882624-44342-4-git-send-email-xieyisheng1@huawei.comSigned-off-by:
Yisheng Xie <xieyisheng1@huawei.com> Acked-by:
Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Chris Salls <salls@cs.ucsb.edu> Cc: Christopher Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Tan Xiaojun <tanxiaojun@huawei.com> Signed-off-by:
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Yisheng Xie authored
[ Upstream commit 56521e7a ] As Xiaojun reported the ltp of migrate_pages01 will fail on arm64 system which has 4 nodes[0...3], all have memory and CONFIG_NODES_SHIFT=2: migrate_pages01 0 TINFO : test_invalid_nodes migrate_pages01 14 TFAIL : migrate_pages_common.c:45: unexpected failure - returned value = 0, expected: -1 migrate_pages01 15 TFAIL : migrate_pages_common.c:55: call succeeded unexpectedly In this case the test_invalid_nodes of migrate_pages01 will call: SYSC_migrate_pages as: migrate_pages(0, , {0x0000000000000001}, 64, , {0x0000000000000010}, 64) = 0 The new nodes specifies one or more node IDs that are greater than the maximum supported node ID, however, the errno is not set to EINVAL as expected. As man pages of set_mempolicy[1], mbind[2], and migrate_pages[3] mentioned, when nodemask specifies one or more node IDs that are greater than the maximum supported node ID, the errno should set to EINVAL. However, get_nodes only check whether the part of bits [BITS_PER_LONG*BITS_TO_LONGS(MAX_NUMNODES), maxnode) is zero or not, and remain [MAX_NUMNODES, BITS_PER_LONG*BITS_TO_LONGS(MAX_NUMNODES) unchecked. This patch is to check the bits of [MAX_NUMNODES, maxnode) in get_nodes to let migrate_pages set the errno to EINVAL when nodemask specifies one or more node IDs that are greater than the maximum supported node ID, which follows the manpage's guide. [1] http://man7.org/linux/man-pages/man2/set_mempolicy.2.html [2] http://man7.org/linux/man-pages/man2/mbind.2.html [3] http://man7.org/linux/man-pages/man2/migrate_pages.2.html Link: http://lkml.kernel.org/r/1510882624-44342-3-git-send-email-xieyisheng1@huawei.comSigned-off-by:
Tan Xiaojun <tanxiaojun@huawei.com> Acked-by:
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