lkml.org 
[lkml]   [2011]   [Sep]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
SubjectRe: [PATCH 0/2] PCI: PCI-E MPS bug fixes
From
Date
On Tue, 2011-09-13 at 07:50 -0300, Benjamin Herrenschmidt wrote:
> >
> > You should apply them. I would queue them, and but I don't have
> > another PCI tree anywhere for you to pull them.
> >
> > In fact, I'll be out for the next few weeks; I'll ask Bjorn to cover
> > for me.
>
> Note that I might be missing some patches, but what's currently in Linus
> tree is rather wrong.
>
> The comment is right, but the implementation is bogus:

Oh and another one (again, I never saw the patches I'm responding to for
some odd reason, only email 0/2, so you might have already fixed that):

When using "safe" mode, I get a crash in pcie_find_smpss(). Patch below.

From 1b542d690323fab332e61099193d598c5c515d13 Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Tue, 13 Sep 2011 15:16:33 -0300
Subject: [PATCH] pci: Don't crash when reading mpss from root complex

In pcie_find_smpss(), we have the following statement:

if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT))
The problem is that at least on my machine, this gets called for the
root complex (virtual P2P bridge), and dev->bus->self is NULL since
the parent bus for this is not itself anchor to a PCI device.

This adds the necessary NULL check.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
drivers/pci/probe.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 8473727..09d1c0f 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1351,7 +1351,8 @@ static int pcie_find_smpss(struct pci_dev *dev, void *data)
* will occur as normal.
*/
if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
- dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT))
+ (dev->bus->self &&
+ dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT)))
*smpss = 0;

if (*smpss > dev->pcie_mpss)
--
1.7.4.1







\
 
 \ /
  Last update: 2011-09-13 20:21    [from the cache]
©2003-2011 Jasper Spaans