Commit db34a363 authored by Jan Beulich's avatar Jan Beulich Committed by Jesse Barnes
Browse files

x86/PCI: config space accessor functions should not ignore the segment argument 



Without this change, the majority of the raw PCI config space access
functions silently ignore a non-zero segment argument, which is
certainly wrong.

Apart from pci_direct_conf1, all other non-MMCFG access methods get
used only for non-extended accesses (i.e. assigned to raw_pci_ops
only). Consequently, with the way raw_pci_{read,write}() work, it would
be a coding error to call these functions with a non-zero segment (with
the current call flow this cannot happen afaict).

The access method 1 accessor, as it can be used for extended accesses
(on AMD systems) instead gets checks added for the passed in segment to
be zero. This would be the case when on such a system having multiple
PCI segments (don't know whether any exist in practice) MMCFG for some
reason is not usable, and method 1 gets selected for doing extended
accesses. Rather than accessing the wrong device's config space, the
function will now error out.

v2: Convert BUG_ON() to WARN_ON(), and extend description as per Ingo's
request.

Signed-off-by: default avatarJan Beulich <jbeulich@novell.com>
Reviewed-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent 688398bb

arch/x86/pci/ce4100.c

+2 −0
Original line number Diff line number Diff line
@@ -257,6 +257,7 @@ static int ce4100_conf_read(unsigned int seg, unsigned int bus, 
{

	int i;



	WARN_ON(seg);

	if (bus == 1) {

		for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {

			if (bus1_fixups[i].dev_func == devfn &&
@@ -282,6 +283,7 @@ static int ce4100_conf_write(unsigned int seg, unsigned int bus, 
{

	int i;



	WARN_ON(seg);

	if (bus == 1) {

		for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {

			if (bus1_fixups[i].dev_func == devfn &&

arch/x86/pci/direct.c

+4 −2
Original line number Diff line number Diff line
@@ -22,7 +22,7 @@ static int pci_conf1_read(unsigned int seg, unsigned int bus, 
{

	unsigned long flags;



	if ((bus > 255) || (devfn > 255) || (reg > 4095)) {

	if (seg || (bus > 255) || (devfn > 255) || (reg > 4095)) {

		*value = -1;

		return -EINVAL;

	}
@@ -53,7 +53,7 @@ static int pci_conf1_write(unsigned int seg, unsigned int bus, 
{

	unsigned long flags;



	if ((bus > 255) || (devfn > 255) || (reg > 4095))

	if (seg || (bus > 255) || (devfn > 255) || (reg > 4095))

		return -EINVAL;



	raw_spin_lock_irqsave(&pci_config_lock, flags);
@@ -97,6 +97,7 @@ static int pci_conf2_read(unsigned int seg, unsigned int bus, 
	unsigned long flags;

	int dev, fn;



	WARN_ON(seg);

	if ((bus > 255) || (devfn > 255) || (reg > 255)) {

		*value = -1;

		return -EINVAL;
@@ -138,6 +139,7 @@ static int pci_conf2_write(unsigned int seg, unsigned int bus, 
	unsigned long flags;

	int dev, fn;



	WARN_ON(seg);

	if ((bus > 255) || (devfn > 255) || (reg > 255)) 

		return -EINVAL;

arch/x86/pci/numaq_32.c

+2 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ static int pci_conf1_mq_read(unsigned int seg, unsigned int bus, 
	unsigned long flags;

	void *adr __iomem = XQUAD_PORT_ADDR(0xcfc, BUS2QUAD(bus));



	WARN_ON(seg);

	if (!value || (bus >= MAX_MP_BUSSES) || (devfn > 255) || (reg > 255))

		return -EINVAL;
@@ -73,6 +74,7 @@ static int pci_conf1_mq_write(unsigned int seg, unsigned int bus, 
	unsigned long flags;

	void *adr __iomem = XQUAD_PORT_ADDR(0xcfc, BUS2QUAD(bus));



	WARN_ON(seg);

	if ((bus >= MAX_MP_BUSSES) || (devfn > 255) || (reg > 255)) 

		return -EINVAL;

arch/x86/pci/olpc.c

+4 −0
Original line number Diff line number Diff line
@@ -206,6 +206,8 @@ static int pci_olpc_read(unsigned int seg, unsigned int bus, 
{

	uint32_t *addr;



	WARN_ON(seg);



	/* Use the hardware mechanism for non-simulated devices */

	if (!is_simulated(bus, devfn))

		return pci_direct_conf1.read(seg, bus, devfn, reg, len, value);
@@ -264,6 +266,8 @@ static int pci_olpc_read(unsigned int seg, unsigned int bus, 
static int pci_olpc_write(unsigned int seg, unsigned int bus,

		unsigned int devfn, int reg, int len, uint32_t value)

{

	WARN_ON(seg);



	/* Use the hardware mechanism for non-simulated devices */

	if (!is_simulated(bus, devfn))

		return pci_direct_conf1.write(seg, bus, devfn, reg, len, value);

arch/x86/pci/pcbios.c

+2 −0
Original line number Diff line number Diff line
@@ -181,6 +181,7 @@ static int pci_bios_read(unsigned int seg, unsigned int bus, 
	unsigned long flags;

	unsigned long bx = (bus << 8) | devfn;



	WARN_ON(seg);

	if (!value || (bus > 255) || (devfn > 255) || (reg > 255))

		return -EINVAL;
@@ -247,6 +248,7 @@ static int pci_bios_write(unsigned int seg, unsigned int bus, 
	unsigned long flags;

	unsigned long bx = (bus << 8) | devfn;



	WARN_ON(seg);

	if ((bus > 255) || (devfn > 255) || (reg > 255)) 

		return -EINVAL;

CRA Git | Maintained and supported by SUSTech CRA and CCSE