On 6/23/21 08:14, David Sterba wrote: > On Wed, Jun 23, 2021 at 08:39:01AM +1000, Stephen Rothwell wrote: >> Hi all, >> >> After merging the kspp-gustavo tree, today's linux-next build (powerpc >> ppc64_defconfig) produced this warning: >> >> In file included from fs/btrfs/ctree.h:9, >> from fs/btrfs/struct-funcs.c:8: >> fs/btrfs/struct-funcs.c: In function 'btrfs_get_token_16': >> fs/btrfs/struct-funcs.c:80:46: warning: array subscript 1 is above array bounds of 'struct page *[1]' [-Warray-bounds] >> 80 | token->kaddr = page_address(token->eb->pages[idx + 1]); \ >> | ~~~~~~~~~~~~~~~~^~~~~~~~~ > > The warning is correct, on powerpc and 64k pages the array has only 1 > item, ie. only index 0 is valid. The overflow won't happen in practice > though because of previous branch that would happen in 100% cases. The > code handles when some bytes cross 2 pages but on 64k pages it's all > just one page. > > To allow the warning to be enabled globally we'll fix it, I'll let > Gustavo know once it's done. Awesome. :) Thanks, David. -- Gustavo
