From: Jan Beulich <jbeulich@xxxxxxxx> commit f28347cc66395e96712f5c2db0a302ee75bafce6 upstream. While working on XSA-361 and its follow-ups, I failed to spot another place where the kernel mapping part of an operation was not treated the same as the user space part. Detect and propagate errors and add a 2nd pr_debug(). Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> Reviewed-by: Juergen Gross <jgross@xxxxxxxx> Link: https://lore.kernel.org/r/c2513395-74dc-aea3-9192-fd265aa44e35@xxxxxxxx Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Signed-off-by: Demi Marie Obenour <demi@xxxxxxxxxxxxxxxxxxxxxx> Co-authored-by: Demi Marie Obenour <demi@xxxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/xen/gntdev.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -419,6 +419,14 @@ static void __unmap_grant_pages_done(int map->unmap_ops[offset+i].handle, map->unmap_ops[offset+i].status); map->unmap_ops[offset+i].handle = -1; + if (use_ptemod) { + WARN_ON(map->kunmap_ops[offset+i].status && + map->kunmap_ops[offset+i].handle != -1); + pr_debug("kunmap handle=%u st=%d\n", + map->kunmap_ops[offset+i].handle, + map->kunmap_ops[offset+i].status); + map->kunmap_ops[offset+i].handle = -1; + } } /* * Decrease the live-grant counter. This must happen after the loop to