| Message ID | 1487245547-24384-13-git-send-email-tom.leiming@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Ming,
[auto build test WARNING on linus/master]
[also build test WARNING on v4.10-rc8]
[cannot apply to next-20170216]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Ming-Lei/md-cleanup-on-direct-access-to-bvec-table/20170216-210357
config: powerpc-cell_defconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All warnings (new ones prefixed by >>):
In file included from arch/powerpc/include/asm/page.h:331:0,
from arch/powerpc/include/asm/thread_info.h:34,
from include/linux/thread_info.h:25,
from include/asm-generic/preempt.h:4,
from ./arch/powerpc/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:59,
from include/linux/spinlock.h:50,
from include/linux/mmzone.h:7,
from include/linux/gfp.h:5,
from include/linux/slab.h:14,
from drivers/md/raid1.c:34:
drivers/md/raid1.c: In function 'raid1d':
>> include/asm-generic/memory_model.h:54:52: warning: 'sbio_pages$' may be used uninitialized in this function [-Wmaybe-uninitialized]
#define __page_to_pfn(page) (unsigned long)((page) - vmemmap)
^
drivers/md/raid1.c:2008:42: note: 'sbio_pages$' was declared here
struct page *pbio_pages[RESYNC_PAGES], *sbio_pages[RESYNC_PAGES];
^~~~~~~~~~
drivers/md/raid1.c:2075:9: warning: 'page_len$' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (memcmp(page_address(p),
^~~~~~~~~~~~~~~~~~~~~~~
page_address(s),
~~~~~~~~~~~~~~~~
page_len[j]))
~~~~~~~~~~~~
drivers/md/raid1.c:2007:6: note: 'page_len$' was declared here
int page_len[RESYNC_PAGES];
^~~~~~~~
In file included from arch/powerpc/include/asm/page.h:331:0,
from arch/powerpc/include/asm/thread_info.h:34,
from include/linux/thread_info.h:25,
from include/asm-generic/preempt.h:4,
from ./arch/powerpc/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:59,
from include/linux/spinlock.h:50,
from include/linux/mmzone.h:7,
from include/linux/gfp.h:5,
from include/linux/slab.h:14,
from drivers/md/raid1.c:34:
>> include/asm-generic/memory_model.h:54:52: warning: 'pbio_pages$' may be used uninitialized in this function [-Wmaybe-uninitialized]
#define __page_to_pfn(page) (unsigned long)((page) - vmemmap)
^
drivers/md/raid1.c:2008:15: note: 'pbio_pages$' was declared here
struct page *pbio_pages[RESYNC_PAGES], *sbio_pages[RESYNC_PAGES];
^~~~~~~~~~
drivers/md/raid1.c:1978:8: warning: 'pages$' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (r1_sync_page_io(rdev, sect, s,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pages[idx],
~~~~~~~~~~~
READ) != 0)
~~~~~
drivers/md/raid1.c:1872:15: note: 'pages$' was declared here
struct page *pages[RESYNC_PAGES];
^~~~~
vim +54 include/asm-generic/memory_model.h
a117e66e KAMEZAWA Hiroyuki 2006-03-27 38 ({ unsigned long __pfn = (pfn); \
c5d71243 Rafael J. Wysocki 2008-11-08 39 unsigned long __nid = arch_pfn_to_nid(__pfn); \
a117e66e KAMEZAWA Hiroyuki 2006-03-27 40 NODE_DATA(__nid)->node_mem_map + arch_local_page_offset(__pfn, __nid);\
a117e66e KAMEZAWA Hiroyuki 2006-03-27 41 })
a117e66e KAMEZAWA Hiroyuki 2006-03-27 42
67de6482 Andy Whitcroft 2006-06-23 43 #define __page_to_pfn(pg) \
aa462abe Ian Campbell 2011-08-17 44 ({ const struct page *__pg = (pg); \
a0140c1d KAMEZAWA Hiroyuki 2006-03-27 45 struct pglist_data *__pgdat = NODE_DATA(page_to_nid(__pg)); \
a0140c1d KAMEZAWA Hiroyuki 2006-03-27 46 (unsigned long)(__pg - __pgdat->node_mem_map) + \
a0140c1d KAMEZAWA Hiroyuki 2006-03-27 47 __pgdat->node_start_pfn; \
a117e66e KAMEZAWA Hiroyuki 2006-03-27 48 })
a117e66e KAMEZAWA Hiroyuki 2006-03-27 49
8f6aac41 Christoph Lameter 2007-10-16 50 #elif defined(CONFIG_SPARSEMEM_VMEMMAP)
8f6aac41 Christoph Lameter 2007-10-16 51
af901ca1 André Goddard Rosa 2009-11-14 52 /* memmap is virtually contiguous. */
8f6aac41 Christoph Lameter 2007-10-16 53 #define __pfn_to_page(pfn) (vmemmap + (pfn))
32272a26 Martin Schwidefsky 2008-12-25 @54 #define __page_to_pfn(page) (unsigned long)((page) - vmemmap)
8f6aac41 Christoph Lameter 2007-10-16 55
a117e66e KAMEZAWA Hiroyuki 2006-03-27 56 #elif defined(CONFIG_SPARSEMEM)
a117e66e KAMEZAWA Hiroyuki 2006-03-27 57 /*
1a49123b Zhang Yanfei 2013-10-03 58 * Note: section's mem_map is encoded to reflect its start_pfn.
a117e66e KAMEZAWA Hiroyuki 2006-03-27 59 * section[i].section_mem_map == mem_map's address - start_pfn;
a117e66e KAMEZAWA Hiroyuki 2006-03-27 60 */
67de6482 Andy Whitcroft 2006-06-23 61 #define __page_to_pfn(pg) \
aa462abe Ian Campbell 2011-08-17 62 ({ const struct page *__pg = (pg); \
:::::: The code at line 54 was first introduced by commit
:::::: 32272a26974d2027384fd4010cd1780fca425d94 [S390] __page_to_pfn warnings
:::::: TO: Martin Schwidefsky <schwidefsky@de.ibm.com>
:::::: CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 4400fbe7ce8c..54ec32be3277 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -2010,6 +2010,9 @@ static void process_checks(struct r1bio *r1_bio) int primary; int i; int vcnt; + struct bio_vec *bi; + int page_len[RESYNC_PAGES]; + struct page *pbio_pages[RESYNC_PAGES], *sbio_pages[RESYNC_PAGES]; /* Fix variable parts of all bios */ vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9); @@ -2017,7 +2020,6 @@ static void process_checks(struct r1bio *r1_bio) int j; int size; int error; - struct bio_vec *bi; struct bio *b = r1_bio->bios[i]; if (b->bi_end_io != end_sync_read) continue; @@ -2051,6 +2053,11 @@ static void process_checks(struct r1bio *r1_bio) break; } r1_bio->read_disk = primary; + + /* .bi_vcnt has been set for all read bios */ + bio_for_each_segment_all(bi, r1_bio->bios[primary], i) + pbio_pages[i] = bi->bv_page; + for (i = 0; i < conf->raid_disks * 2; i++) { int j; struct bio *pbio = r1_bio->bios[primary]; @@ -2062,14 +2069,19 @@ static void process_checks(struct r1bio *r1_bio) /* Now we can 'fixup' the error value */ sbio->bi_error = 0; + bio_for_each_segment_all(bi, sbio, j) { + sbio_pages[j] = bi->bv_page; + page_len[j] = bi->bv_len; + } + if (!error) { for (j = vcnt; j-- ; ) { struct page *p, *s; - p = pbio->bi_io_vec[j].bv_page; - s = sbio->bi_io_vec[j].bv_page; + p = pbio_pages[j]; + s = sbio_pages[j]; if (memcmp(page_address(p), page_address(s), - sbio->bi_io_vec[j].bv_len)) + page_len[j])) break; } } else
Given process_checks is only called in resync path, it should be ok to allocate three stack variable(total 320byteds) to store pages from bios. Signed-off-by: Ming Lei <tom.leiming@gmail.com> --- drivers/md/raid1.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)