| Message ID | 105ed603-971a-e7db-6040-b85e5eecd928@redhat.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On 5/22/17 10:48 AM, Eric Sandeen wrote: > This was throwing unaligned access warnings on sparc64: > > Kernel unaligned access at TPC[1043c088] xfs_btree_visit_blocks+0x88/0xe0 [xfs] > > Signed-off-by: Eric Sandeen <sandeen@redhat.com> > --- (FYI lightly tested only - did a mount & fs traversal of the fs in question with this patch) -Eric > diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c > index 5392674..84089f8 100644 > --- a/fs/xfs/libxfs/xfs_btree.c > +++ b/fs/xfs/libxfs/xfs_btree.c > @@ -4395,7 +4395,7 @@ struct xfs_btree_split_args { > xfs_btree_readahead_ptr(cur, ptr, 1); > > /* save for the next iteration of the loop */ > - lptr = *ptr; > + lptr = get_unaligned(ptr); > } > > /* for each buffer in the level */ > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, May 22, 2017 at 10:48:14AM -0500, Eric Sandeen wrote: > This was throwing unaligned access warnings on sparc64: > > Kernel unaligned access at TPC[1043c088] xfs_btree_visit_blocks+0x88/0xe0 [xfs] > > Signed-off-by: Eric Sandeen <sandeen@redhat.com> > --- > > diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c > index 5392674..84089f8 100644 > --- a/fs/xfs/libxfs/xfs_btree.c > +++ b/fs/xfs/libxfs/xfs_btree.c > @@ -4395,7 +4395,7 @@ struct xfs_btree_split_args { > xfs_btree_readahead_ptr(cur, ptr, 1); > > /* save for the next iteration of the loop */ > - lptr = *ptr; > + lptr = get_unaligned(ptr); Hm.. We don't really do this for the return value of of xfs_btree_ptr_addr anywhere else. So if it really returns something not suitably enough aligned we're in much deeper trouble. -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 5/22/17 2:07 PM, Christoph Hellwig wrote: > On Mon, May 22, 2017 at 10:48:14AM -0500, Eric Sandeen wrote: >> This was throwing unaligned access warnings on sparc64: >> >> Kernel unaligned access at TPC[1043c088] xfs_btree_visit_blocks+0x88/0xe0 [xfs] >> >> Signed-off-by: Eric Sandeen <sandeen@redhat.com> >> --- >> >> diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c >> index 5392674..84089f8 100644 >> --- a/fs/xfs/libxfs/xfs_btree.c >> +++ b/fs/xfs/libxfs/xfs_btree.c >> @@ -4395,7 +4395,7 @@ struct xfs_btree_split_args { >> xfs_btree_readahead_ptr(cur, ptr, 1); >> >> /* save for the next iteration of the loop */ >> - lptr = *ptr; >> + lptr = get_unaligned(ptr); > > Hm.. We don't really do this for the return value of of xfs_btree_ptr_addr > anywhere else. So if it really returns something not suitably enough > aligned we're in much deeper trouble. Yeah, I took a quick look, probably too quick. But I think the problem here is that it's a structure copy, which is unusual compared to most of the other callers: union xfs_btree_ptr lptr; lptr = *ptr; and is probably what's generating the warning, right? I guess a better comment and/or commit log would be in order. I haven't looked at every other caller but several end up calling xfs_btree_copy_ptrs which does a memcpy. Hm, ok, maybe we should just be using that helper... xfs_btree_copy_ptrs(cur, &lptr, ptr, 1); ? -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c index 5392674..84089f8 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -4395,7 +4395,7 @@ struct xfs_btree_split_args { xfs_btree_readahead_ptr(cur, ptr, 1); /* save for the next iteration of the loop */ - lptr = *ptr; + lptr = get_unaligned(ptr); } /* for each buffer in the level */
This was throwing unaligned access warnings on sparc64: Kernel unaligned access at TPC[1043c088] xfs_btree_visit_blocks+0x88/0xe0 [xfs] Signed-off-by: Eric Sandeen <sandeen@redhat.com> --- -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html