The patch titled Subject: kexec: add cond_resched into kimage_alloc_crash_control_pages has been added to the -mm tree. Its filename is kexec-add-cond_resched-into-kimage_alloc_crash_control_pages.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/kexec-add-cond_resched-into-kimage_alloc_crash_control_pages.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/kexec-add-cond_resched-into-kimage_alloc_crash_control_pages.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: zhong jiang <zhongjiang@xxxxxxxxxx> Subject: kexec: add cond_resched into kimage_alloc_crash_control_pages A soft lookup will occur when I run trinity in syscall kexec_load. the corresponding stack information is as follows. [ 237.235937] BUG: soft lockup - CPU#6 stuck for 22s! [trinity-c6:13859] [ 237.242699] Kernel panic - not syncing: softlockup: hung tasks [ 237.248573] CPU: 6 PID: 13859 Comm: trinity-c6 Tainted: G O L ----V------- 3.10.0-327.28.3.35.zhongjiang.x86_64 #1 [ 237.259984] Hardware name: Huawei Technologies Co., Ltd. Tecal BH622 V2/BC01SRSA0, BIOS RMIBV386 06/30/2014 [ 237.269752] ffffffff8187626b 0000000018cfde31 ffff88184c803e18 ffffffff81638f16 [ 237.277471] ffff88184c803e98 ffffffff8163278f 0000000000000008 ffff88184c803ea8 [ 237.285190] ffff88184c803e48 0000000018cfde31 ffff88184c803e67 0000000000000000 [ 237.292909] Call Trace: [ 237.295404] <IRQ> [<ffffffff81638f16>] dump_stack+0x19/0x1b [ 237.301352] [<ffffffff8163278f>] panic+0xd8/0x214 [ 237.306196] [<ffffffff8111d6fc>] watchdog_timer_fn+0x1cc/0x1e0 [ 237.312157] [<ffffffff8111d530>] ? watchdog_enable+0xc0/0xc0 [ 237.317955] [<ffffffff810aa182>] __hrtimer_run_queues+0xd2/0x260 [ 237.324087] [<ffffffff810aa720>] hrtimer_interrupt+0xb0/0x1e0 [ 237.329963] [<ffffffff8164ae5c>] ? call_softirq+0x1c/0x30 [ 237.335500] [<ffffffff81049a77>] local_apic_timer_interrupt+0x37/0x60 [ 237.342228] [<ffffffff8164bacf>] smp_apic_timer_interrupt+0x3f/0x60 [ 237.348771] [<ffffffff8164a11d>] apic_timer_interrupt+0x6d/0x80 [ 237.354967] <EOI> [<ffffffff810f3a00>] ? kimage_alloc_control_pages+0x80/0x270 [ 237.362875] [<ffffffff811c3ebe>] ? kmem_cache_alloc_trace+0x1ce/0x1f0 [ 237.369592] [<ffffffff810f362f>] ? do_kimage_alloc_init+0x1f/0x90 [ 237.375992] [<ffffffff810f3d1a>] kimage_alloc_init+0x12a/0x180 [ 237.382103] [<ffffffff810f3f9a>] SyS_kexec_load+0x20a/0x260 [ 237.387957] [<ffffffff816494c9>] system_call_fastpath+0x16/0x1b the first time allocation of control pages may take too much time because crash_res.end can be set to a higher value. we need to add cond_resched to avoid the issue. The patch have been tested and above issue is not appear. Link: http://lkml.kernel.org/r/1481164674-42775-1-git-send-email-zhongjiang@xxxxxxxxxx Signed-off-by: zhong jiang <zhongjiang@xxxxxxxxxx> Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Cc: Xunlei Pang <xpang@xxxxxxxxxx> Cc: Dave Young <dyoung@xxxxxxxxxx> Cc: Vivek Goyal <vgoyal@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/kexec_core.c | 2 ++ 1 file changed, 2 insertions(+) diff -puN kernel/kexec_core.c~kexec-add-cond_resched-into-kimage_alloc_crash_control_pages kernel/kexec_core.c --- a/kernel/kexec_core.c~kexec-add-cond_resched-into-kimage_alloc_crash_control_pages +++ a/kernel/kexec_core.c @@ -441,6 +441,8 @@ static struct page *kimage_alloc_crash_c while (hole_end <= crashk_res.end) { unsigned long i; + cond_resched(); + if (hole_end > KEXEC_CRASH_CONTROL_MEMORY_LIMIT) break; /* See if I overlap any of the segments */ _ Patches currently in -mm which might be from zhongjiang@xxxxxxxxxx are z3fold-limit-first_num-to-the-actual-range-of-possible-buddy-indexes.patch mm-page_owner-align-with-pageblock_nr-pages.patch mm-walk-the-zone-in-pageblock_nr_pages-steps.patch kexec-add-cond_resched-into-kimage_alloc_crash_control_pages.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html