* Re: smatch warnings in current upstream kernel
2012-09-11 10:51 smatch warnings in current upstream kernel Dan Carpenter
@ 2012-09-11 11:06 ` Fengguang Wu
2012-09-11 14:29 ` Dan Carpenter
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Fengguang Wu @ 2012-09-11 11:06 UTC (permalink / raw)
To: kernel-janitors
On Tue, Sep 11, 2012 at 01:51:27PM +0300, Dan Carpenter wrote:
> On Tue, Sep 11, 2012 at 06:10:02PM +0800, Fengguang Wu wrote:
> > Here are the 7161 smatch warnings for 2139 files in upstream head
> > 1a95620f45155ac523cd1419d89150fbb4eb858b. It's not a complete build
> > (no make clean), so does not include all possible warnings.
> >
>
> There are some sparse warnings mixed in as well. They would have
> been sent to stderr and smatch warnings get sent to stdout.
Thanks for pointing this out!
> But if you want you could look at smatch_scripts/test_kernel.sh
> which allows for a parallel build and saves all the warnings in
> warns.txt.
Yeah I looked at the script, however did not want to touch the source
tree, so...
> I guess you have your own parallel build technique as well and that
> works too.
I have a tiny smatch wrapper script for passing to CHECK=.
According to your advice, I will only save its stdout:
$SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
Thanks,
Fengguang
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: smatch warnings in current upstream kernel
2012-09-11 10:51 smatch warnings in current upstream kernel Dan Carpenter
2012-09-11 11:06 ` Fengguang Wu
@ 2012-09-11 14:29 ` Dan Carpenter
2012-09-11 14:49 ` Fengguang Wu
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Dan Carpenter @ 2012-09-11 14:29 UTC (permalink / raw)
To: kernel-janitors
On Tue, Sep 11, 2012 at 07:06:40PM +0800, Fengguang Wu wrote:
> On Tue, Sep 11, 2012 at 01:51:27PM +0300, Dan Carpenter wrote:
>
> $SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
Some of the warnings you are getting seem to mean that you're not
picking up the smatch_data/ directory. For example some of the
buffer overflow errors:
drivers/mtd/ubi/wl.c:336 prot_queue_add() warn: buffer overflow 'ubi->pq' 10 <= 10
What is happening in that function is that Smatch sees the:
ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN);
and assumes that since there is a test for
"pq_tail < UBI_PROT_QUEUE_LEN" then it must be possible for
pq_tail = UBI_PROT_QUEUE_LEN. There is a file called:
smatch_data/kernel.ignored_macros which has ubi_assert() and it
means to ignore everything that happens inside a ubi_assert().
Normally Smatch looks for the data dir with the binary, but you can
also specify a directory with --data=/path/to/smatch_data/. Then
you can test that it's working by doing a:
kchecker drivers/mtd/ubi/wl.c
to verify that the warning goes away.
It may cause a lot of new warnings to show up though...
regards,
dan carpenter
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: smatch warnings in current upstream kernel
2012-09-11 10:51 smatch warnings in current upstream kernel Dan Carpenter
2012-09-11 11:06 ` Fengguang Wu
2012-09-11 14:29 ` Dan Carpenter
@ 2012-09-11 14:49 ` Fengguang Wu
2012-09-12 2:48 ` Fengguang Wu
2012-09-12 6:26 ` Dan Carpenter
4 siblings, 0 replies; 6+ messages in thread
From: Fengguang Wu @ 2012-09-11 14:49 UTC (permalink / raw)
To: kernel-janitors
On Tue, Sep 11, 2012 at 05:29:26PM +0300, Dan Carpenter wrote:
> On Tue, Sep 11, 2012 at 07:06:40PM +0800, Fengguang Wu wrote:
> > On Tue, Sep 11, 2012 at 01:51:27PM +0300, Dan Carpenter wrote:
> >
> > $SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
FYI, the wrapper script is as simple as
SMATCH=/c/smatch/smatch
$SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
> Some of the warnings you are getting seem to mean that you're not
> picking up the smatch_data/ directory. For example some of the
> buffer overflow errors:
>
> drivers/mtd/ubi/wl.c:336 prot_queue_add() warn: buffer overflow 'ubi->pq' 10 <= 10
>
> What is happening in that function is that Smatch sees the:
> ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN);
>
> and assumes that since there is a test for
> "pq_tail < UBI_PROT_QUEUE_LEN" then it must be possible for
> pq_tail = UBI_PROT_QUEUE_LEN. There is a file called:
> smatch_data/kernel.ignored_macros which has ubi_assert() and it
> means to ignore everything that happens inside a ubi_assert().
Yes, I can see the data and function. Thank you very much for the tips!
> Normally Smatch looks for the data dir with the binary, but you can
> also specify a directory with --data=/path/to/smatch_data/. Then
The directory layout here is
/c/smatch/ # git tree
/c/smatch/smatch # binary
/c/smatch/smatch_data/ # kernel.* data
> you can test that it's working by doing a:
> kchecker drivers/mtd/ubi/wl.c
> to verify that the warning goes away.
Both of these two tests run well w/o the above warning:
/c/smatch/smatch_scripts/kchecker drivers/mtd/ubi/wl.c
make C=1 CHECK=/c/kernel-tests/smatchcheck drivers/mtd/ubi/wl.o
This is interesting. I'll try adding --data=/c/smatch/smatch_data and
check whether the end result becomes better.
Thanks,
Fengguang
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: smatch warnings in current upstream kernel
2012-09-11 10:51 smatch warnings in current upstream kernel Dan Carpenter
` (2 preceding siblings ...)
2012-09-11 14:49 ` Fengguang Wu
@ 2012-09-12 2:48 ` Fengguang Wu
2012-09-12 6:26 ` Dan Carpenter
4 siblings, 0 replies; 6+ messages in thread
From: Fengguang Wu @ 2012-09-12 2:48 UTC (permalink / raw)
To: kernel-janitors
On Tue, Sep 11, 2012 at 10:49:39PM +0800, Fengguang Wu wrote:
> On Tue, Sep 11, 2012 at 05:29:26PM +0300, Dan Carpenter wrote:
> > On Tue, Sep 11, 2012 at 07:06:40PM +0800, Fengguang Wu wrote:
> > > On Tue, Sep 11, 2012 at 01:51:27PM +0300, Dan Carpenter wrote:
> > >
> > > $SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
>
> FYI, the wrapper script is as simple as
>
> SMATCH=/c/smatch/smatch
> $SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
>
> > Some of the warnings you are getting seem to mean that you're not
> > picking up the smatch_data/ directory. For example some of the
> > buffer overflow errors:
> >
> > drivers/mtd/ubi/wl.c:336 prot_queue_add() warn: buffer overflow 'ubi->pq' 10 <= 10
> >
> > What is happening in that function is that Smatch sees the:
> > ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN);
> >
> > and assumes that since there is a test for
> > "pq_tail < UBI_PROT_QUEUE_LEN" then it must be possible for
> > pq_tail = UBI_PROT_QUEUE_LEN. There is a file called:
> > smatch_data/kernel.ignored_macros which has ubi_assert() and it
> > means to ignore everything that happens inside a ubi_assert().
>
> Yes, I can see the data and function. Thank you very much for the tips!
>
> > Normally Smatch looks for the data dir with the binary, but you can
> > also specify a directory with --data=/path/to/smatch_data/. Then
>
> The directory layout here is
>
> /c/smatch/ # git tree
> /c/smatch/smatch # binary
> /c/smatch/smatch_data/ # kernel.* data
>
> > you can test that it's working by doing a:
> > kchecker drivers/mtd/ubi/wl.c
> > to verify that the warning goes away.
>
> Both of these two tests run well w/o the above warning:
>
> /c/smatch/smatch_scripts/kchecker drivers/mtd/ubi/wl.c
>
> make C=1 CHECK=/c/kernel-tests/smatchcheck drivers/mtd/ubi/wl.o
>
> This is interesting. I'll try adding --data=/c/smatch/smatch_data and
> check whether the end result becomes better.
It works now, after changing '-p kernel' to '--project=kernel'.
Next step would be to regenerate the smatch_data/ contents for each
new branch to make it work more reliably.
Thanks,
Fengguang
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: smatch warnings in current upstream kernel
2012-09-11 10:51 smatch warnings in current upstream kernel Dan Carpenter
` (3 preceding siblings ...)
2012-09-12 2:48 ` Fengguang Wu
@ 2012-09-12 6:26 ` Dan Carpenter
4 siblings, 0 replies; 6+ messages in thread
From: Dan Carpenter @ 2012-09-12 6:26 UTC (permalink / raw)
To: kernel-janitors
On Wed, Sep 12, 2012 at 10:48:42AM +0800, Fengguang Wu wrote:
> On Tue, Sep 11, 2012 at 10:49:39PM +0800, Fengguang Wu wrote:
> > On Tue, Sep 11, 2012 at 05:29:26PM +0300, Dan Carpenter wrote:
> > > On Tue, Sep 11, 2012 at 07:06:40PM +0800, Fengguang Wu wrote:
> > > > On Tue, Sep 11, 2012 at 01:51:27PM +0300, Dan Carpenter wrote:
> > > >
> > > > $SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
> >
> > FYI, the wrapper script is as simple as
> >
> > SMATCH=/c/smatch/smatch
> > $SMATCH -p kernel "$@" > $SMATCH_OUT_ROOT/$PPID-$$-$RANDOM
> >
> > > Some of the warnings you are getting seem to mean that you're not
> > > picking up the smatch_data/ directory. For example some of the
> > > buffer overflow errors:
> > >
> > > drivers/mtd/ubi/wl.c:336 prot_queue_add() warn: buffer overflow 'ubi->pq' 10 <= 10
> > >
> > > What is happening in that function is that Smatch sees the:
> > > ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN);
> > >
> > > and assumes that since there is a test for
> > > "pq_tail < UBI_PROT_QUEUE_LEN" then it must be possible for
> > > pq_tail = UBI_PROT_QUEUE_LEN. There is a file called:
> > > smatch_data/kernel.ignored_macros which has ubi_assert() and it
> > > means to ignore everything that happens inside a ubi_assert().
> >
> > Yes, I can see the data and function. Thank you very much for the tips!
> >
> > > Normally Smatch looks for the data dir with the binary, but you can
> > > also specify a directory with --data=/path/to/smatch_data/. Then
> >
> > The directory layout here is
> >
> > /c/smatch/ # git tree
> > /c/smatch/smatch # binary
> > /c/smatch/smatch_data/ # kernel.* data
> >
> > > you can test that it's working by doing a:
> > > kchecker drivers/mtd/ubi/wl.c
> > > to verify that the warning goes away.
> >
> > Both of these two tests run well w/o the above warning:
> >
> > /c/smatch/smatch_scripts/kchecker drivers/mtd/ubi/wl.c
> >
> > make C=1 CHECK=/c/kernel-tests/smatchcheck drivers/mtd/ubi/wl.o
> >
> > This is interesting. I'll try adding --data=/c/smatch/smatch_data and
> > check whether the end result becomes better.
>
> It works now, after changing '-p kernel' to '--project=kernel'.
Oops. Yeah. -p=kernel would also work.
>
> Next step would be to regenerate the smatch_data/ contents for each
> new branch to make it work more reliably.
>
The smatch_scripts/build_kernel_data.sh does this.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 6+ messages in thread