| Message ID | 1496199416-2556-1-git-send-email-baijiaju1990@163.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
>-----Original Message----- >From: Jia-Ju Bai [mailto:baijiaju1990@163.com] >Sent: Wednesday, May 31, 2017 8:27 AM >To: kashyap.desai@broadcom.com; sumit.saxena@broadcom.com; >shivasharan.srikanteshwara@broadcom.com; jejb@linux.vnet.ibm.com; >martin.petersen@oracle.com >Cc: megaraidlinux.pdl@broadcom.com; linux-scsi@vger.kernel.org; linux- >kernel@vger.kernel.org; Jia-Ju Bai >Subject: [PATCH] megaraid: Fix a sleep-in-atomic bug > >The driver may sleep under a spin lock, and the function call path is: >mraid_mm_attach_buf (acquire the lock by spin_lock_irqsave) > pci_pool_alloc(GFP_KERNEL) --> may sleep > >To fix it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC". > >Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com> >--- > drivers/scsi/megaraid/megaraid_mm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >diff --git a/drivers/scsi/megaraid/megaraid_mm.c >b/drivers/scsi/megaraid/megaraid_mm.c >index 4cf9ed9..c43afb8 100644 >--- a/drivers/scsi/megaraid/megaraid_mm.c >+++ b/drivers/scsi/megaraid/megaraid_mm.c >@@ -574,7 +574,7 @@ > > kioc->pool_index = right_pool; > kioc->free_buf = 1; >- kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_KERNEL, >+ kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_ATOMIC, > &kioc->buf_paddr); > spin_unlock_irqrestore(&pool->lock, flags); This is very old driver and reached EOL. Did you face any issue because of this bug or discover this through code review? Anyways patch looks good to me. Acked-by: Sumit Saxena <sumit.saxena@broadcom.com> > >-- >1.7.9.5 >
On 05/31/2017 06:18 PM, Sumit Saxena wrote: >> -----Original Message----- >> From: Jia-Ju Bai [mailto:baijiaju1990@163.com] >> Sent: Wednesday, May 31, 2017 8:27 AM >> To: kashyap.desai@broadcom.com; sumit.saxena@broadcom.com; >> shivasharan.srikanteshwara@broadcom.com; jejb@linux.vnet.ibm.com; >> martin.petersen@oracle.com >> Cc: megaraidlinux.pdl@broadcom.com; linux-scsi@vger.kernel.org; linux- >> kernel@vger.kernel.org; Jia-Ju Bai >> Subject: [PATCH] megaraid: Fix a sleep-in-atomic bug >> >> The driver may sleep under a spin lock, and the function call path is: >> mraid_mm_attach_buf (acquire the lock by spin_lock_irqsave) >> pci_pool_alloc(GFP_KERNEL) --> may sleep >> >> To fix it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC". >> >> Signed-off-by: Jia-Ju Bai<baijiaju1990@163.com> >> --- >> drivers/scsi/megaraid/megaraid_mm.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/scsi/megaraid/megaraid_mm.c >> b/drivers/scsi/megaraid/megaraid_mm.c >> index 4cf9ed9..c43afb8 100644 >> --- a/drivers/scsi/megaraid/megaraid_mm.c >> +++ b/drivers/scsi/megaraid/megaraid_mm.c >> @@ -574,7 +574,7 @@ >> >> kioc->pool_index = right_pool; >> kioc->free_buf = 1; >> - kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_KERNEL, >> + kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_ATOMIC, >> &kioc->buf_paddr); >> spin_unlock_irqrestore(&pool->lock, flags); > This is very old driver and reached EOL. Did you face any issue because of > this bug or discover this through code review? > Anyways patch looks good to me. > > Acked-by: Sumit Saxena<sumit.saxena@broadcom.com> > >> -- >> 1.7.9.5 >> Hi, This bug is found by a static analysis tool and my code review. Jia-Ju Bai
diff --git a/drivers/scsi/megaraid/megaraid_mm.c b/drivers/scsi/megaraid/megaraid_mm.c index 4cf9ed9..c43afb8 100644 --- a/drivers/scsi/megaraid/megaraid_mm.c +++ b/drivers/scsi/megaraid/megaraid_mm.c @@ -574,7 +574,7 @@ kioc->pool_index = right_pool; kioc->free_buf = 1; - kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_KERNEL, + kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_ATOMIC, &kioc->buf_paddr); spin_unlock_irqrestore(&pool->lock, flags);
The driver may sleep under a spin lock, and the function call path is: mraid_mm_attach_buf (acquire the lock by spin_lock_irqsave) pci_pool_alloc(GFP_KERNEL) --> may sleep To fix it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC". Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com> --- drivers/scsi/megaraid/megaraid_mm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)