| Message ID | 1397490316.2207.23.camel@dabdike.int.hansenpartnership.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Mon, Apr 14, 2014 at 08:45:16AM -0700, James Bottomley wrote: > Your subject line is very tame. It should be the one line summary of > why we apply the patch, so it should read something like > > hpsa: fix NULL deref in performant mode > > On Thu, 2014-04-10 at 17:17 -0500, scameron@beardog.cce.hp.com wrote: > > Without this, you'll see a null pointer dereference in > > hpsa_enter_performant_mode(). > > The description should be more comprehensible. > > I'm clear that the use before initialisation is a bug ... I'm less clear > on why it causes an oops. > > > Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> > > --- > > drivers/scsi/hpsa.c | 4 ++++ > > 1 files changed, 4 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c > > index 8cf4a0c..ef4dfdd 100644 > > --- a/drivers/scsi/hpsa.c > > +++ b/drivers/scsi/hpsa.c > > @@ -7463,6 +7463,10 @@ static void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) > > if (hpsa_simple_mode) > > return; > > > > + trans_support = readl(&(h->cfgtable->TransportSupport)); > > + if (!(trans_support & PERFORMANT_MODE)) > > + return; > > + > > /* Check for I/O accelerator mode support */ > > if (trans_support & CFGTBL_Trans_io_accel1) { > > transMethod |= CFGTBL_Trans_io_accel1 | > > Shouldn't you be moving this check from its previous location, rather > than adding a new one that makes the original obsolete? Oh... I didn't notice that. So that's what happened to that hunk. Yes, that is what should be done. I will resend the patch after fixing up this and the commit message. -- steve > > James > > --- > > diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c > index 8cf4a0c..9a6e4a2 100644 > --- a/drivers/scsi/hpsa.c > +++ b/drivers/scsi/hpsa.c > @@ -7463,6 +7463,10 @@ static void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) > if (hpsa_simple_mode) > return; > > + trans_support = readl(&(h->cfgtable->TransportSupport)); > + if (!(trans_support & PERFORMANT_MODE)) > + return; > + > /* Check for I/O accelerator mode support */ > if (trans_support & CFGTBL_Trans_io_accel1) { > transMethod |= CFGTBL_Trans_io_accel1 | > @@ -7479,10 +7483,6 @@ static void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) > } > > /* TODO, check that this next line h->nreply_queues is correct */ > - trans_support = readl(&(h->cfgtable->TransportSupport)); > - if (!(trans_support & PERFORMANT_MODE)) > - return; > - > h->nreply_queues = h->msix_vector > 0 ? h->msix_vector : 1; > hpsa_get_max_perf_mode_cmds(h); > /* Performant mode ring buffer and supporting data structures */ > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 8cf4a0c..9a6e4a2 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -7463,6 +7463,10 @@ static void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) if (hpsa_simple_mode) return; + trans_support = readl(&(h->cfgtable->TransportSupport)); + if (!(trans_support & PERFORMANT_MODE)) + return; + /* Check for I/O accelerator mode support */ if (trans_support & CFGTBL_Trans_io_accel1) { transMethod |= CFGTBL_Trans_io_accel1 | @@ -7479,10 +7483,6 @@ static void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) } /* TODO, check that this next line h->nreply_queues is correct */ - trans_support = readl(&(h->cfgtable->TransportSupport)); - if (!(trans_support & PERFORMANT_MODE)) - return; - h->nreply_queues = h->msix_vector > 0 ? h->msix_vector : 1; hpsa_get_max_perf_mode_cmds(h); /* Performant mode ring buffer and supporting data structures */