On Mon, Jul 22, 2024 at 04:22:45PM -0400, Liam R. Howlett wrote: > The problem report from [2] and [3] is that we are getting to a call > path that includes unmap_single_vma() without the mmap lock. This patch > fails to address that issue, it only takes the caller with the assert > out of the call path. > > Removing the function with the lock check doesn't fix the locking issue. > If there is no locking issue here, please state the case in the commit > log as you feel it is safe to use a vma pointer without the mmap_lock > held. Could you please state why there's a locking issue, and why this patch (of a x86 PAT specific issue...) would need any documentation on that? I thought it was pretty common that file truncation (or anything similar) does a file rmap walk over vmas that mapping this file, and vmas need to be alive during the rmap walk, no? Thanks, -- Peter Xu
