在 2022/10/22 AM4:01, Tony Luck 写道: > Part 1 deals with the process that triggered the copy on write > fault with a store to a shared read-only page. That process is > send a SIGBUS with the usual machine check decoration to specify > the virtual address of the lost page, together with the scope. > > Part 2 sets up to asynchronously take the page with the uncorrected > error offline to prevent additional machine check faults. H/t to > Miaohe Lin <linmiaohe@xxxxxxxxxx> and Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx> > for pointing me to the existing function to queue a call to > memory_failure(). > > On x86 there is some duplicate reporting (because the error is > also signalled by the memory controller as well as by the core > that triggered the machine check). Console logs look like this: > > [ 1647.723403] mce: [Hardware Error]: Machine check events logged > Machine check from kernel copy routine > > [ 1647.723414] MCE: Killing einj_mem_uc:3600 due to hardware memory corruption fault at 7f3309503400 > x86 fault handler sends SIGBUS to child process > > [ 1647.735183] Memory failure: 0x905b92d: recovery action for dirty LRU page: Recovered > Async call to memory_failure() from copy on write path The recovery action might also be handled asynchronously in CMCI uc_decode_notifier handler signaled by memory controller, right? I have a one more memory failure log than yours. [ 3187.485742] MCE: Killing einj_mem_uc:31746 due to hardware memory corruption fault at 7fc4bf7cf400 [ 3187.740620] Memory failure: 0x1a3b80: recovery action for dirty LRU page: Recovered uc_decode_notifier() processes memory controller report [ 3187.748272] Memory failure: 0x1a3b80: already hardware poisoned Workqueue: events memory_failure_work_func // queued by ghes_do_memory_failure [ 3187.754194] Memory failure: 0x1a3b80: already hardware poisoned Workqueue: events memory_failure_work_func // queued by __wp_page_copy_user [ 3188.615920] MCE: Killing einj_mem_uc:31745 due to hardware memory corruption fault at 7fc4bf7cf400 Best Regards, Shuai > > [ 1647.748397] Memory failure: 0x905b92d: already hardware poisoned > uc_decode_notifier() processes memory controller report > > [ 1647.761313] MCE: Killing einj_mem_uc:3599 due to hardware memory corruption fault at 7f3309503400 > Parent process tries to read poisoned page. Page has been unmapped, so > #PF handler sends SIGBUS > > > Tony Luck (2): > mm, hwpoison: Try to recover from copy-on write faults > mm, hwpoison: When copy-on-write hits poison, take page offline > > include/linux/highmem.h | 24 ++++++++++++++++++++++++ > include/linux/mm.h | 5 ++++- > mm/memory.c | 32 ++++++++++++++++++++++---------- > 3 files changed, 50 insertions(+), 11 deletions(-) >
