Re: [PATCH] perf/x86/intel/uncore: Avoid null dereferences (uncore_extra_pci_dev)
On 4/15/2021 5:19 PM, Liang, Kan wrote:
Hi Steve,
On 4/15/2021 4:37 PM, Steve Wahl wrote:
If an uncore has no pci_init routine, or that routine fails,
uncore_pci_init is not called, and memory is not allocated for
uncore_extra_pci_dev.
So check to make sure uncore_extra_pci_dev is not NULL before use.
I think more after yesterday's discussion. There may be a better
solution than this.
Actually, we don't have to probe all the PCU devices and stores them
into the uncore_extra_pci_dev for the cpu_init().
We just need to pick up the first PCU device and check the existence of
the SBOX once.
I will send out a patch shortly.
Here is the patch I mentioned.
https://lore.kernel.org/lkml/1618521764-100923-1-git-send-email-kan.li...@linux.intel.com
Thanks,
Kan
And fix the case that led us to discover the null derefs; don't fail
snbep_pci2phy_map_init if BIOS doesn't supply pcibus_to_node
information.
Fixes: 9a7832ce3d92 ("perf/x86/intel/uncore: With > 8 nodes, get pci
bus die id from NUMA info")
In theory, the pci_read_config_dword() may fails as well. It has
possible that the issue can still be observed before the "> 8 nodes" patch.
I think the fixes should be 5306c31c5733 ("perf/x86/uncore/hsw-ep:
Handle systems with only two SBOXes")
Thanks,
Kan
Signed-off-by: Steve Wahl
---
arch/x86/events/intel/uncore_snbep.c | 10 +++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/x86/events/intel/uncore_snbep.c
b/arch/x86/events/intel/uncore_snbep.c
index b79951d0707c..14c24356a2fa 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -1373,11 +1373,11 @@ static int snbep_pci2phy_map_init(int devid,
int nodeid_loc, int idmap_loc, bool
/*
* The nodeid and idmap registers only contain enough
* information to handle 8 nodes. On systems with more
- * than 8 nodes, we need to rely on NUMA information,
+ * than 8 nodes, if available we rely on NUMA information,
* filled in from BIOS supplied information, to determine
* the topology.
*/
- if (nr_node_ids <= 8) {
+ if ((nr_node_ids <= 8) || (pcibus_to_node(ubox_dev->bus) ==
-1)) {
/* get the Node ID of the local register */
err = pci_read_config_dword(ubox_dev, nodeid_loc, );
if (err)
@@ -2865,7 +2865,9 @@ void hswep_uncore_cpu_init(void)
hswep_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
/* Detect 6-8 core systems with only two SBOXes */
- if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
+ if (!uncore_extra_pci_dev)
+ hswep_uncore_sbox.num_boxes = 2;
+ else if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
u32 capid4;
pci_read_config_dword(uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3],
@@ -3243,6 +3245,8 @@ void bdx_uncore_cpu_init(void)
if (boot_cpu_data.x86_model == 86) {
uncore_msr_uncores[BDX_MSR_UNCORE_SBOX] = NULL;
/* Detect systems with no SBOXes */
+ } else if (!uncore_extra_pci_dev) {
+ bdx_msr_uncores[BDX_MSR_UNCORE_SBOX] = NULL;
} else if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
struct pci_dev *pdev;
u32 capid4;
Re: [PATCH] perf/x86/intel/uncore: Avoid null dereferences (uncore_extra_pci_dev)
Hi Steve,
On 4/15/2021 4:37 PM, Steve Wahl wrote:
If an uncore has no pci_init routine, or that routine fails,
uncore_pci_init is not called, and memory is not allocated for
uncore_extra_pci_dev.
So check to make sure uncore_extra_pci_dev is not NULL before use.
I think more after yesterday's discussion. There may be a better
solution than this.
Actually, we don't have to probe all the PCU devices and stores them
into the uncore_extra_pci_dev for the cpu_init().
We just need to pick up the first PCU device and check the existence of
the SBOX once.
I will send out a patch shortly.
And fix the case that led us to discover the null derefs; don't fail
snbep_pci2phy_map_init if BIOS doesn't supply pcibus_to_node
information.
Fixes: 9a7832ce3d92 ("perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from
NUMA info")
In theory, the pci_read_config_dword() may fails as well. It has
possible that the issue can still be observed before the "> 8 nodes" patch.
I think the fixes should be 5306c31c5733 ("perf/x86/uncore/hsw-ep:
Handle systems with only two SBOXes")
Thanks,
Kan
Signed-off-by: Steve Wahl
---
arch/x86/events/intel/uncore_snbep.c | 10 +++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/x86/events/intel/uncore_snbep.c
b/arch/x86/events/intel/uncore_snbep.c
index b79951d0707c..14c24356a2fa 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -1373,11 +1373,11 @@ static int snbep_pci2phy_map_init(int devid, int
nodeid_loc, int idmap_loc, bool
/*
* The nodeid and idmap registers only contain enough
* information to handle 8 nodes. On systems with more
-* than 8 nodes, we need to rely on NUMA information,
+* than 8 nodes, if available we rely on NUMA information,
* filled in from BIOS supplied information, to determine
* the topology.
*/
- if (nr_node_ids <= 8) {
+ if ((nr_node_ids <= 8) || (pcibus_to_node(ubox_dev->bus) ==
-1)) {
/* get the Node ID of the local register */
err = pci_read_config_dword(ubox_dev, nodeid_loc,
);
if (err)
@@ -2865,7 +2865,9 @@ void hswep_uncore_cpu_init(void)
hswep_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
/* Detect 6-8 core systems with only two SBOXes */
- if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
+ if (!uncore_extra_pci_dev)
+ hswep_uncore_sbox.num_boxes = 2;
+ else if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
u32 capid4;
pci_read_config_dword(uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3],
@@ -3243,6 +3245,8 @@ void bdx_uncore_cpu_init(void)
if (boot_cpu_data.x86_model == 86) {
uncore_msr_uncores[BDX_MSR_UNCORE_SBOX] = NULL;
/* Detect systems with no SBOXes */
+ } else if (!uncore_extra_pci_dev) {
+ bdx_msr_uncores[BDX_MSR_UNCORE_SBOX] = NULL;
} else if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
struct pci_dev *pdev;
u32 capid4;
[PATCH] perf/x86/intel/uncore: Avoid null dereferences (uncore_extra_pci_dev)
If an uncore has no pci_init routine, or that routine fails,
uncore_pci_init is not called, and memory is not allocated for
uncore_extra_pci_dev.
So check to make sure uncore_extra_pci_dev is not NULL before use.
And fix the case that led us to discover the null derefs; don't fail
snbep_pci2phy_map_init if BIOS doesn't supply pcibus_to_node
information.
Fixes: 9a7832ce3d92 ("perf/x86/intel/uncore: With > 8 nodes, get pci bus die id
from NUMA info")
Signed-off-by: Steve Wahl
---
arch/x86/events/intel/uncore_snbep.c | 10 +++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/x86/events/intel/uncore_snbep.c
b/arch/x86/events/intel/uncore_snbep.c
index b79951d0707c..14c24356a2fa 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -1373,11 +1373,11 @@ static int snbep_pci2phy_map_init(int devid, int
nodeid_loc, int idmap_loc, bool
/*
* The nodeid and idmap registers only contain enough
* information to handle 8 nodes. On systems with more
-* than 8 nodes, we need to rely on NUMA information,
+* than 8 nodes, if available we rely on NUMA information,
* filled in from BIOS supplied information, to determine
* the topology.
*/
- if (nr_node_ids <= 8) {
+ if ((nr_node_ids <= 8) || (pcibus_to_node(ubox_dev->bus) ==
-1)) {
/* get the Node ID of the local register */
err = pci_read_config_dword(ubox_dev, nodeid_loc,
);
if (err)
@@ -2865,7 +2865,9 @@ void hswep_uncore_cpu_init(void)
hswep_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
/* Detect 6-8 core systems with only two SBOXes */
- if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
+ if (!uncore_extra_pci_dev)
+ hswep_uncore_sbox.num_boxes = 2;
+ else if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
u32 capid4;
pci_read_config_dword(uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3],
@@ -3243,6 +3245,8 @@ void bdx_uncore_cpu_init(void)
if (boot_cpu_data.x86_model == 86) {
uncore_msr_uncores[BDX_MSR_UNCORE_SBOX] = NULL;
/* Detect systems with no SBOXes */
+ } else if (!uncore_extra_pci_dev) {
+ bdx_msr_uncores[BDX_MSR_UNCORE_SBOX] = NULL;
} else if (uncore_extra_pci_dev[pkg].dev[HSWEP_PCI_PCU_3]) {
struct pci_dev *pdev;
u32 capid4;
--
2.26.2
