lkml.org 
[lkml]   [2010]   [Jul]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] x86/pci/mrst: add extra check in fixed bar detection
Date
Fixed bar capability structure is searched in PCI extended configuration
space. We need to make sure there is a valid capability id to begin with
otherwise, the search code may stuck in a infinite loop which results in
boot hang.
This patch adds additional check for cap ID 0, which is also invalid.

Suggested-by: "H. Peter Anvin" <hpa@zytor.com>

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
arch/x86/pci/mrst.c | 7 ++++---
1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/pci/mrst.c b/arch/x86/pci/mrst.c
index c9649d0..8636567 100644
--- a/arch/x86/pci/mrst.c
+++ b/arch/x86/pci/mrst.c
@@ -66,8 +66,9 @@ static int fixed_bar_cap(struct pci_bus *bus, unsigned int devfn)
devfn, pos, 4, &pcie_cap))
return 0;

- if (pcie_cap == 0xffffffff)
- return 0;
+ if (PCI_EXT_CAP_ID(pcie_cap) == 0x0000 ||
+ PCI_EXT_CAP_ID(pcie_cap) == 0xffff)
+ break;

if (PCI_EXT_CAP_ID(pcie_cap) == PCI_EXT_CAP_ID_VNDR) {
raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
@@ -76,7 +77,7 @@ static int fixed_bar_cap(struct pci_bus *bus, unsigned int devfn)
return pos;
}

- pos = pcie_cap >> 20;
+ pos = PCI_EXT_CAP_NEXT(pcie_cap);
}

return 0;
--
1.7.0.4


\
 
 \ /
  Last update: 2010-07-16 21:09    [W:0.043 / U:1.732 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site