On Fri, 2018-10-12 at 21:29 -0700, Dan Williams wrote: > The device-dax unit test sometimes fails with the following kernel > message signature: > > Memory failure: Unable to find user space address 204300 in lt-device-dax > Memory failure: 0x204300: forcibly killing lt-device-dax:1334 because of > failure to unmap > > This happens when there is a 3rd party vma in the rmap that has an entry > at the same index as the currently failing page. While the test has > munmap()'d the previous mapping we still trip over the fact that the > kernel memory-failure code does not differentiate munmap vs mremap and > upgrades the failure to process fatal. > > The add_to_kill() routine in the kernel has a comment that says: > > /* > * In theory we don't have to kill when the page was > * munmaped. But it could be also a mremap. Since that's > * likely very rare kill anyways just out of paranoia, but use > * a SIGKILL because the error is not contained anymore. > */ > > ...when it is determining what to do when it can't find the given pfn > mapped into the process at the given index. > > Avoid this case by munmap()'ing *and* closing the file to trigger old / > stale vma's to be reaped. With that the only vma that can be looked up > is the one the error was injected, the lookup succeeds, and the test > passes. > > Signed-off-by: Dan Williams <[email protected]> > --- > test/device-dax.c | 49 ++++++++++++++++++++++++++++++++++--------------- > 1 file changed, 34 insertions(+), 15 deletions(-)
Looks good, applied. > > _______________________________________________ Linux-nvdimm mailing list [email protected] https://lists.01.org/mailman/listinfo/linux-nvdimm
