| Message ID | 20240522181308.841686-1-pchelkin@ispras.ru (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] dma-buf: handle testing kthreads creation failure | expand |
On Wed, May 22, 2024 at 11:14 AM Fedor Pchelkin <pchelkin@ispras.ru> wrote: > > kthread creation may possibly fail inside race_signal_callback(). In > such a case stop the already started threads, put the already taken > references to them and return with error code. > > Found by Linux Verification Center (linuxtesting.org). > > Fixes: 2989f6451084 ("dma-buf: Add selftests for dma-fence") > Cc: stable@vger.kernel.org > Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Reviewed-by: T.J. Mercier <tjmercier@google.com> > --- > v2: use kthread_stop_put() to actually put the last reference as > T.J. Mercier noticed; > link to v1: https://lore.kernel.org/lkml/20240522122326.696928-1-pchelkin@ispras.ru/ > > drivers/dma-buf/st-dma-fence.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/dma-buf/st-dma-fence.c b/drivers/dma-buf/st-dma-fence.c > index b7c6f7ea9e0c..6a1bfcd0cc21 100644 > --- a/drivers/dma-buf/st-dma-fence.c > +++ b/drivers/dma-buf/st-dma-fence.c > @@ -540,6 +540,12 @@ static int race_signal_callback(void *arg) > t[i].before = pass; > t[i].task = kthread_run(thread_signal_callback, &t[i], > "dma-fence:%d", i); > + if (IS_ERR(t[i].task)) { > + ret = PTR_ERR(t[i].task); > + while (--i >= 0) > + kthread_stop_put(t[i].task); > + return ret; > + } > get_task_struct(t[i].task); > } > > -- > 2.39.2 >
Am 22.05.24 um 20:33 schrieb T.J. Mercier: > On Wed, May 22, 2024 at 11:14 AM Fedor Pchelkin <pchelkin@ispras.ru> wrote: >> kthread creation may possibly fail inside race_signal_callback(). In >> such a case stop the already started threads, put the already taken >> references to them and return with error code. >> >> Found by Linux Verification Center (linuxtesting.org). >> >> Fixes: 2989f6451084 ("dma-buf: Add selftests for dma-fence") >> Cc: stable@vger.kernel.org >> Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> > Reviewed-by: T.J. Mercier <tjmercier@google.com> Just FYI: I've picked this one up and pushed it to drm-misc-fixes. Regards, Christian. >> --- >> v2: use kthread_stop_put() to actually put the last reference as >> T.J. Mercier noticed; >> link to v1: https://lore.kernel.org/lkml/20240522122326.696928-1-pchelkin@ispras.ru/ >> >> drivers/dma-buf/st-dma-fence.c | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/drivers/dma-buf/st-dma-fence.c b/drivers/dma-buf/st-dma-fence.c >> index b7c6f7ea9e0c..6a1bfcd0cc21 100644 >> --- a/drivers/dma-buf/st-dma-fence.c >> +++ b/drivers/dma-buf/st-dma-fence.c >> @@ -540,6 +540,12 @@ static int race_signal_callback(void *arg) >> t[i].before = pass; >> t[i].task = kthread_run(thread_signal_callback, &t[i], >> "dma-fence:%d", i); >> + if (IS_ERR(t[i].task)) { >> + ret = PTR_ERR(t[i].task); >> + while (--i >= 0) >> + kthread_stop_put(t[i].task); >> + return ret; >> + } >> get_task_struct(t[i].task); >> } >> >> -- >> 2.39.2 >>
diff --git a/drivers/dma-buf/st-dma-fence.c b/drivers/dma-buf/st-dma-fence.c index b7c6f7ea9e0c..6a1bfcd0cc21 100644 --- a/drivers/dma-buf/st-dma-fence.c +++ b/drivers/dma-buf/st-dma-fence.c @@ -540,6 +540,12 @@ static int race_signal_callback(void *arg) t[i].before = pass; t[i].task = kthread_run(thread_signal_callback, &t[i], "dma-fence:%d", i); + if (IS_ERR(t[i].task)) { + ret = PTR_ERR(t[i].task); + while (--i >= 0) + kthread_stop_put(t[i].task); + return ret; + } get_task_struct(t[i].task); }
kthread creation may possibly fail inside race_signal_callback(). In such a case stop the already started threads, put the already taken references to them and return with error code. Found by Linux Verification Center (linuxtesting.org). Fixes: 2989f6451084 ("dma-buf: Add selftests for dma-fence") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> --- v2: use kthread_stop_put() to actually put the last reference as T.J. Mercier noticed; link to v1: https://lore.kernel.org/lkml/20240522122326.696928-1-pchelkin@ispras.ru/ drivers/dma-buf/st-dma-fence.c | 6 ++++++ 1 file changed, 6 insertions(+)