On Mon, Jan 9, 2023 at 2:52 AM Ashish Sadanandan <[email protected]> wrote: > > The code added for allowing --huge-dir to specify hugetlbfs > sub-directories has a bug where it incorrectly matches mounts that > contain a prefix of the specified --huge-dir. > > Consider --huge-dir=/dev/hugepages1G is passed to rte_eal_init. Given > the following hugetlbfs mounts > > $ mount | grep hugetlbfs > hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M) > hugetlbfs on /dev/hugepages1G type hugetlbfs (rw,relatime,pagesize=1024M) > hugetlbfs on /mnt/huge type hugetlbfs (rw,relatime,pagesize=2M) > > get_hugepage_dir is first called with hugepage_sz=2097152. While > iterating over all mount points, /dev/hugepages is incorrectly > determined to be a match because it's a prefix of --huge-dir. The caller > then obtains an exclusive lock on --huge-dir. > > In the next call to get_hugepage_dir, hugepage_sz=1073741824. This call > correctly determines /dev/hugepages1G is a match. The caller again > attempts to obtain an exclusive lock on --huge-dir and deadlocks because > it's already holding a lock. > > This has been corrected by ensuring any matched mount point is either an > exact match or a parent path of --huge-dir. > > Fixes: 24d5a1ce6b85 ("eal/linux: allow hugetlbfs sub-directories") > Cc: [email protected]
> Signed-off-by: Ashish Sadanandan <[email protected]> Reviewed-by: John Levon <[email protected]> I got pinged by Julien who reported a similar issue. He confirmed later that this fix works for him too. Tested-by: Julien Meunier <[email protected]> Applied, thanks Ashish. -- David Marchand
