diff options
| author | Demi Marie Obenour <demi@invisiblethingslab.com> | 2022-07-10 19:05:22 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-29 17:10:30 +0200 |
| commit | 39b8cdd153c3dd45e6bb5ea0fd9cd80f74deef9c (patch) | |
| tree | 15a21a60c754c5d077bed02cb70dd56b739af285 | |
| parent | d2da5392d208b6790056b4ff5108bc8807691207 (diff) | |
xen/gntdev: Ignore failure to unmap INVALID_GRANT_HANDLE
commit 166d3863231667c4f64dee72b77d1102cdfad11f upstream.
The error paths of gntdev_mmap() can call unmap_grant_pages() even
though not all of the pages have been successfully mapped. This will
trigger the WARN_ON()s in __unmap_grant_pages_done(). The number of
warnings can be very large; I have observed thousands of lines of
warnings in the systemd journal.
Avoid this problem by only warning on unmapping failure if the handle
being unmapped is not INVALID_GRANT_HANDLE. The handle field of any
page that was not successfully mapped will be INVALID_GRANT_HANDLE, so
this catches all cases where unmapping can legitimately fail.
Fixes: dbe97cff7dd9 ("xen/gntdev: Avoid blocking in unmap_grant_pages()")
Cc: stable@vger.kernel.org
Suggested-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220710230522.1563-1-demi@invisiblethingslab.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/xen/gntdev.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 492084814f55..27d955c5d9f9 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -416,7 +416,8 @@ static void __unmap_grant_pages_done(int result, unsigned int offset = data->unmap_ops - map->unmap_ops; for (i = 0; i < data->count; i++) { - WARN_ON(map->unmap_ops[offset+i].status); + WARN_ON(map->unmap_ops[offset+i].status && + map->unmap_ops[offset+i].handle != -1); pr_debug("unmap handle=%d st=%d\n", map->unmap_ops[offset+i].handle, map->unmap_ops[offset+i].status); |