2007-10-05 20:19:32

by Randy Dunlap

[permalink] [raw]
Subject: [PATCH] pci: implement "pci=noaer"

From: Randy Dunlap <[email protected]>

For cases in which CONFIG_PCIEAER=y (such as distro kernels), allow users
to disable PCIE Advanced Error Reporting by using "pci=noaer" on the
kernel command line.

This can be used to work around hardware or (kernel) software problems.

Signed-off-by: Randy Dunlap <[email protected]>
---
Documentation/kernel-parameters.txt | 4 ++++
drivers/pci/pci.c | 2 ++
drivers/pci/pci.h | 6 ++++++
drivers/pci/pcie/aer/aerdrv.c | 9 +++++++++
4 files changed, 21 insertions(+)

--- linux-2.6.23-rc9.orig/Documentation/kernel-parameters.txt
+++ linux-2.6.23-rc9/Documentation/kernel-parameters.txt
@@ -67,6 +67,7 @@ parameter is applicable:
PARIDE The ParIDE (parallel port IDE) subsystem is enabled.
PARISC The PA-RISC architecture is enabled.
PCI PCI bus support is enabled.
+ PCIE PCI Express support is enabled.
PCMCIA The PCMCIA subsystem is enabled.
PNP Plug & Play support is enabled.
PPC PowerPC architecture is enabled.
@@ -1269,6 +1270,9 @@ and is between 256 and 4096 characters.
Mechanism 1.
conf2 [X86-32] Force use of PCI Configuration
Mechanism 2.
+ noaer [PCIE] If the PCIEAER kernel config parameter is
+ enabled, this kernel boot option can be used to
+ disable the use of PCIE advanced error reporting.
nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI
Configuration
nomsi [MSI] If the PCI_MSI kernel config parameter is
--- linux-2.6.23-rc9.orig/drivers/pci/pci.c
+++ linux-2.6.23-rc9/drivers/pci/pci.c
@@ -1585,6 +1585,8 @@ static int __devinit pci_setup(char *str
if (*str && (str = pcibios_setup(str)) && *str) {
if (!strcmp(str, "nomsi")) {
pci_no_msi();
+ } else if (!strcmp(str, "noaer")) {
+ pci_no_aer();
} else if (!strncmp(str, "cbiosize=", 9)) {
pci_cardbus_io_size = memparse(str + 9, &str);
} else if (!strncmp(str, "cbmemsize=", 10)) {
--- linux-2.6.23-rc9.orig/drivers/pci/pci.h
+++ linux-2.6.23-rc9/drivers/pci/pci.h
@@ -52,6 +52,12 @@ void pci_restore_msi_state(struct pci_de
static inline void pci_restore_msi_state(struct pci_dev *dev) {}
#endif

+#ifdef CONFIG_PCIEAER
+void pci_no_aer(void);
+#else
+static inline void pci_no_aer(void) { }
+#endif
+
static inline int pci_no_d1d2(struct pci_dev *dev)
{
unsigned int parent_dstates = 0;
--- linux-2.6.23-rc9.orig/drivers/pci/pcie/aer/aerdrv.c
+++ linux-2.6.23-rc9/drivers/pci/pcie/aer/aerdrv.c
@@ -81,6 +81,13 @@ static struct pcie_port_service_driver a
.reset_link = aer_root_reset,
};

+static int pcie_aer_disable;
+
+void pci_no_aer(void)
+{
+ pcie_aer_disable = 1; /* has priority over 'forceload' */
+}
+
/**
* aer_irq - Root Port's ISR
* @irq: IRQ assigned to Root Port
@@ -327,6 +334,8 @@ static void aer_error_resume(struct pci_
**/
static int __init aer_service_init(void)
{
+ if (pcie_aer_disable)
+ return -ENXIO;
return pcie_port_service_register(&aerdriver);
}


2007-10-15 17:12:54

by linas

[permalink] [raw]
Subject: Re: [PATCH] pci: implement "pci=noaer"



On Fri, Oct 05, 2007 at 01:17:58PM -0700, Randy Dunlap wrote:
> From: Randy Dunlap <[email protected]>
>
> For cases in which CONFIG_PCIEAER=y (such as distro kernels), allow users
> to disable PCIE Advanced Error Reporting by using "pci=noaer" on the
> kernel command line.

Looks reasonable to me.

(sorry for the belated reply... I also saw this in gregkh's patch
series. Since the email was addressed to me, I figure I should
at least say "yes I read it". Dunno if "Yes-I-read-it-by:" is
the same as "Acked by:", if it is, then acked-by me.. )

--linas