* ipc/shm.c:494:18: warning: unused variable ‘hs’ [-Wunused-variable]
@ 2013-05-08 14:34 Borislav Petkov
2013-05-08 16:12 ` Naoya Horiguchi
0 siblings, 1 reply; 6+ messages in thread
From: Borislav Petkov @ 2013-05-08 14:34 UTC (permalink / raw)
To: Naoya Horiguchi; +Cc: lkml
Hi,
looks like this warning came in with
af73e4d9506d3b797509f3c030e7dcd554f7d9c4 and fires in the
# CONFIG_HUGETLB_PAGE is not set
case because
struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT)
& SHM_HUGE_MASK);
becomes
struct hstate *hs = ((void *)0)
due to
#define hstate_sizelog(s) NULL
Hmmm, I don't have a quick solution off the top of my head from staring
at the code.
--
Regards/Gruss,
Boris.
Sent from a fat crate under my desk. Formatting is fine.
--
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: ipc/shm.c:494:18: warning: unused variable ‘hs’ [-Wunused-variable] 2013-05-08 14:34 ipc/shm.c:494:18: warning: unused variable ‘hs’ [-Wunused-variable] Borislav Petkov @ 2013-05-08 16:12 ` Naoya Horiguchi 2013-05-08 18:45 ` Borislav Petkov 0 siblings, 1 reply; 6+ messages in thread From: Naoya Horiguchi @ 2013-05-08 16:12 UTC (permalink / raw) To: Borislav Petkov; +Cc: lkml Hi Borislav, On Wed, May 08, 2013 at 04:34:11PM +0200, Borislav Petkov wrote: > Hi, > > looks like this warning came in with > af73e4d9506d3b797509f3c030e7dcd554f7d9c4 and fires in the > > # CONFIG_HUGETLB_PAGE is not set > > case because > > struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) > & SHM_HUGE_MASK); > > becomes > > struct hstate *hs = ((void *)0) > > due to > > #define hstate_sizelog(s) NULL > > Hmmm, I don't have a quick solution off the top of my head from staring > at the code. Thank you for the report. I believe we can fix it with this one. --- From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Date: Wed, 8 May 2013 11:48:01 -0400 Subject: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() This patch fixes "warning: unused variable 'hs'" when !CONFIG_HUGETLB_PAGE introduced by commit af73e4d9506d "hugetlbfs: fix mmap failure in unaligned size request". Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> --- ipc/shm.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/ipc/shm.c b/ipc/shm.c index e316cb9..9ff741a 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) sprintf (name, "SYSV%08x", key); if (shmflg & SHM_HUGETLB) { - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) - & SHM_HUGE_MASK); - size_t hugesize = ALIGN(size, huge_page_size(hs)); + size_t hugesize = ALIGN(size, huge_page_size(hstate_sizelog( + (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK))); /* hugetlb_file_setup applies strict accounting */ if (shmflg & SHM_NORESERVE) -- 1.7.11.7 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: ipc/shm.c:494:18: warning: unused variable ‘hs’ [-Wunused-variable] 2013-05-08 16:12 ` Naoya Horiguchi @ 2013-05-08 18:45 ` Borislav Petkov 2013-05-08 20:48 ` [PATCH] ipc/shm.c: don't use auto variable hs in newseg() Naoya Horiguchi 0 siblings, 1 reply; 6+ messages in thread From: Borislav Petkov @ 2013-05-08 18:45 UTC (permalink / raw) To: Naoya Horiguchi; +Cc: lkml On Wed, May 08, 2013 at 12:12:32PM -0400, Naoya Horiguchi wrote: > Thank you for the report. > I believe we can fix it with this one. > --- > From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > Date: Wed, 8 May 2013 11:48:01 -0400 > Subject: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() > > This patch fixes "warning: unused variable 'hs'" when !CONFIG_HUGETLB_PAGE > introduced by commit af73e4d9506d "hugetlbfs: fix mmap failure in unaligned > size request". > > Reported-by: Borislav Petkov <bp@alien8.de> > Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > --- > ipc/shm.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/ipc/shm.c b/ipc/shm.c > index e316cb9..9ff741a 100644 > --- a/ipc/shm.c > +++ b/ipc/shm.c > @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) > > sprintf (name, "SYSV%08x", key); > if (shmflg & SHM_HUGETLB) { > - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) > - & SHM_HUGE_MASK); > - size_t hugesize = ALIGN(size, huge_page_size(hs)); > + size_t hugesize = ALIGN(size, huge_page_size(hstate_sizelog( > + (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK))); Yeah, it fixes the warning alright but makes the code more unreadable. Which makes me wonder which is worse - to have an innocuous warning or have unreadable code. You could also do the below. The line sticks out but it kills the warning. Readability is hmm, not optimal still though. :) -- diff --git a/ipc/shm.c b/ipc/shm.c --- a/ipc/shm.c +++ b/ipc/shm.c @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) sprintf (name, "SYSV%08x", key); if (shmflg & SHM_HUGETLB) { - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) - & SHM_HUGE_MASK); - size_t hugesize = ALIGN(size, huge_page_size(hs)); + unsigned long hsz = huge_page_size(hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK)); + size_t hugesize = ALIGN(size, hsz); /* hugetlb_file_setup applies strict accounting */ if (shmflg & SHM_NORESERVE) -- Yeah, you decide. Thanks. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. -- ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ipc/shm.c: don't use auto variable hs in newseg() 2013-05-08 18:45 ` Borislav Petkov @ 2013-05-08 20:48 ` Naoya Horiguchi 2013-05-17 20:31 ` KOSAKI Motohiro 0 siblings, 1 reply; 6+ messages in thread From: Naoya Horiguchi @ 2013-05-08 20:48 UTC (permalink / raw) To: Borislav Petkov; +Cc: lkml, Andrew Morton, linux-mm On Wed, May 08, 2013 at 08:45:24PM +0200, Borislav Petkov wrote: > On Wed, May 08, 2013 at 12:12:32PM -0400, Naoya Horiguchi wrote: > > Thank you for the report. > > I believe we can fix it with this one. > > --- > > From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > > Date: Wed, 8 May 2013 11:48:01 -0400 > > Subject: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() > > > > This patch fixes "warning: unused variable 'hs'" when !CONFIG_HUGETLB_PAGE > > introduced by commit af73e4d9506d "hugetlbfs: fix mmap failure in unaligned > > size request". > > > > Reported-by: Borislav Petkov <bp@alien8.de> > > Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > > --- > > ipc/shm.c | 5 ++--- > > 1 file changed, 2 insertions(+), 3 deletions(-) > > > > diff --git a/ipc/shm.c b/ipc/shm.c > > index e316cb9..9ff741a 100644 > > --- a/ipc/shm.c > > +++ b/ipc/shm.c > > @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) > > > > sprintf (name, "SYSV%08x", key); > > if (shmflg & SHM_HUGETLB) { > > - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) > > - & SHM_HUGE_MASK); > > - size_t hugesize = ALIGN(size, huge_page_size(hs)); > > + size_t hugesize = ALIGN(size, huge_page_size(hstate_sizelog( > > + (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK))); > > Yeah, it fixes the warning alright but makes the code more unreadable. > Which makes me wonder which is worse - to have an innocuous warning or > have unreadable code. > > You could also do the below. The line sticks out but it kills the > warning. Readability is hmm, not optimal still though. :) > -- > diff --git a/ipc/shm.c b/ipc/shm.c > --- a/ipc/shm.c > +++ b/ipc/shm.c > @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) > > sprintf (name, "SYSV%08x", key); > if (shmflg & SHM_HUGETLB) { > - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) > - & SHM_HUGE_MASK); > - size_t hugesize = ALIGN(size, huge_page_size(hs)); > + unsigned long hsz = huge_page_size(hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK)); > + size_t hugesize = ALIGN(size, hsz); > > /* hugetlb_file_setup applies strict accounting */ > if (shmflg & SHM_NORESERVE) > -- > > Yeah, you decide. (CCed: Andrew and linux-mm) OK, personally both are OK (comparably bad) for me, so I'll do the same as af73e4d9506d3b does for SYSCALL_DEFINE6(mmap_pgoff), where we have a line break just after '('. Andrew, could you pick up the following fix? ----- From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Date: Wed, 8 May 2013 11:48:01 -0400 Subject: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() This patch fixes "warning: unused variable 'hs'" when !CONFIG_HUGETLB_PAGE introduced by commit af73e4d9506d "hugetlbfs: fix mmap failure in unaligned size request". Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> --- ipc/shm.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/ipc/shm.c b/ipc/shm.c index e316cb9..9ff741a 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) sprintf (name, "SYSV%08x", key); if (shmflg & SHM_HUGETLB) { - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) - & SHM_HUGE_MASK); - size_t hugesize = ALIGN(size, huge_page_size(hs)); + size_t hugesize = ALIGN(size, huge_page_size(hstate_sizelog( + (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK))); /* hugetlb_file_setup applies strict accounting */ if (shmflg & SHM_NORESERVE) -- 1.7.11.7 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() 2013-05-08 20:48 ` [PATCH] ipc/shm.c: don't use auto variable hs in newseg() Naoya Horiguchi @ 2013-05-17 20:31 ` KOSAKI Motohiro 2013-05-18 1:46 ` Naoya Horiguchi 0 siblings, 1 reply; 6+ messages in thread From: KOSAKI Motohiro @ 2013-05-17 20:31 UTC (permalink / raw) To: Naoya Horiguchi Cc: Borislav Petkov, lkml, Andrew Morton, linux-mm, kosaki.motohiro > From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > Date: Wed, 8 May 2013 11:48:01 -0400 > Subject: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() > > This patch fixes "warning: unused variable 'hs'" when !CONFIG_HUGETLB_PAGE > introduced by commit af73e4d9506d "hugetlbfs: fix mmap failure in unaligned > size request". > > Reported-by: Borislav Petkov <bp@alien8.de> > Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > --- > ipc/shm.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/ipc/shm.c b/ipc/shm.c > index e316cb9..9ff741a 100644 > --- a/ipc/shm.c > +++ b/ipc/shm.c > @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) > > sprintf (name, "SYSV%08x", key); > if (shmflg & SHM_HUGETLB) { > - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) > - & SHM_HUGE_MASK); > - size_t hugesize = ALIGN(size, huge_page_size(hs)); > + size_t hugesize = ALIGN(size, huge_page_size(hstate_sizelog( > + (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK))); NAK. This is uglier than before. You should change !CONFIG_HUGETLB_PAGE specific code instead. ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() 2013-05-17 20:31 ` KOSAKI Motohiro @ 2013-05-18 1:46 ` Naoya Horiguchi 0 siblings, 0 replies; 6+ messages in thread From: Naoya Horiguchi @ 2013-05-18 1:46 UTC (permalink / raw) To: KOSAKI Motohiro; +Cc: Borislav Petkov, lkml, Andrew Morton, linux-mm On Fri, May 17, 2013 at 04:31:52PM -0400, KOSAKI Motohiro wrote: > > From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > > Date: Wed, 8 May 2013 11:48:01 -0400 > > Subject: [PATCH] ipc/shm.c: don't use auto variable hs in newseg() > > > > This patch fixes "warning: unused variable 'hs'" when !CONFIG_HUGETLB_PAGE > > introduced by commit af73e4d9506d "hugetlbfs: fix mmap failure in unaligned > > size request". > > > > Reported-by: Borislav Petkov <bp@alien8.de> > > Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > > --- > > ipc/shm.c | 5 ++--- > > 1 file changed, 2 insertions(+), 3 deletions(-) > > > > diff --git a/ipc/shm.c b/ipc/shm.c > > index e316cb9..9ff741a 100644 > > --- a/ipc/shm.c > > +++ b/ipc/shm.c > > @@ -491,9 +491,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) > > > > sprintf (name, "SYSV%08x", key); > > if (shmflg & SHM_HUGETLB) { > > - struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) > > - & SHM_HUGE_MASK); > > - size_t hugesize = ALIGN(size, huge_page_size(hs)); > > + size_t hugesize = ALIGN(size, huge_page_size(hstate_sizelog( > > + (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK))); > > NAK. This is uglier than before. > You should change !CONFIG_HUGETLB_PAGE specific code instead. This patch was dropped and replaced with Li Zefan's one which is available in current upstream. commit 091d0d55b286c9340201b4ed4470be87fc568228 Author: Li Zefan <lizefan@huawei.com> Date: Thu May 9 15:08:15 2013 +0800 Thanks, Naoya Horiguchi ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-05-18 1:47 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2013-05-08 14:34 ipc/shm.c:494:18: warning: unused variable ‘hs’ [-Wunused-variable] Borislav Petkov 2013-05-08 16:12 ` Naoya Horiguchi 2013-05-08 18:45 ` Borislav Petkov 2013-05-08 20:48 ` [PATCH] ipc/shm.c: don't use auto variable hs in newseg() Naoya Horiguchi 2013-05-17 20:31 ` KOSAKI Motohiro 2013-05-18 1:46 ` Naoya Horiguchi
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox