6.6-stable review patch. If anyone has any objections, please let me know.
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From: Kajol Jain kjain@linux.ibm.com
[ Upstream commit 070b71f428facd9130319707db854ed8bd24637a ]
To access hv-gpci kernel interface files data, the "Enable Performance Information Collection" option has to be set in hmc. Incase that option is not set and user try to read the interface files, it should give error message as operation not permitted.
Result of accessing added interface files with disabled performance collection option:
[command]# cat processor_bus_topology cat: processor_bus_topology: Operation not permitted
[command]# cat processor_config cat: processor_config: Operation not permitted
[command]# cat affinity_domain_via_domain cat: affinity_domain_via_domain: Operation not permitted
[command]# cat affinity_domain_via_virtual_processor cat: affinity_domain_via_virtual_processor: Operation not permitted
[command]# cat affinity_domain_via_partition
Based on above result there is no error message when reading affinity_domain_via_partition file because of missing check for failed hcall. Fix this issue by adding a check in the start of affinity_domain_via_partition_show function, to return error incase hcall fails, with error type other then H_PARAMETER.
Fixes: a15e0d6a6929 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show affinity domain via partition information") Reported-by: Disha Goel disgoel@linux.vnet.ibm.com Signed-off-by: Kajol Jain kjain@linux.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://msgid.link/20231116122033.160964-1-kjain@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/perf/hv-gpci.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/arch/powerpc/perf/hv-gpci.c b/arch/powerpc/perf/hv-gpci.c index 39dbe6b348df..27f18119fda1 100644 --- a/arch/powerpc/perf/hv-gpci.c +++ b/arch/powerpc/perf/hv-gpci.c @@ -534,6 +534,9 @@ static ssize_t affinity_domain_via_partition_show(struct device *dev, struct dev if (!ret) goto parse_result;
+ if (ret && (ret != H_PARAMETER)) + goto out; + /* * ret value as 'H_PARAMETER' implies that the current buffer size * can't accommodate all the information, and a partial buffer