Commit e7aff647 authored by Jithu Joseph's avatar Jithu Joseph Committed by Aichun Shi
Browse files

platform/x86/intel/ifs: release cpus_read_lock() 

mainline inclusion
from mainline-v6.6-rc5
commit 2545deba
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/IB4HZ4
CVE: N/A
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2545deba314eec91dc5ca1a954fe97f91ef1cf07



-------------------------------------

Couple of error paths in do_core_test() was returning directly without
doing a necessary cpus_read_unlock().

Following lockdep warning was observed when exercising these scenarios
with PROVE_RAW_LOCK_NESTING enabled:

[  139.304775] ================================================
[  139.311185] WARNING: lock held when returning to user space!
[  139.317593] 6.6.0-rc2ifs01+ #11 Tainted: G S      W I
[  139.324499] ------------------------------------------------
[  139.330908] bash/11476 is leaving the kernel with locks still held!
[  139.338000] 1 lock held by bash/11476:
[  139.342262]  #0: ffffffffaa26c930 (cpu_hotplug_lock){++++}-{0:0}, at:
do_core_test+0x35/0x1c0 [intel_ifs]

Fix the flow so that all scenarios release the lock prior to returning
from the function.

Intel-SIG: commit 2545deba platform/x86/intel/ifs: release cpus_read_lock()
Backport to fix IFS(In Field Scan) SAF(Scan At Field)

Fixes: 5210fb4e ("platform/x86/intel/ifs: Sysfs interface for Array BIST")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarJithu Joseph <jithu.joseph@intel.com>
Link: https://lore.kernel.org/r/20230927184824.2566086-1-jithu.joseph@intel.com


Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
[ Aichun Shi: amend commit log ]
Signed-off-by: default avatarAichun Shi <aichun.shi@intel.com>
parent 16c2bddc

drivers/platform/x86/intel/ifs/runtest.c

+4 −3
Original line number Diff line number Diff line
@@ -331,14 +331,15 @@ int do_core_test(int cpu, struct device *dev) 
	switch (test->test_num) {

	case IFS_TYPE_SAF:

		if (!ifsd->loaded)

			return -EPERM;

			ret = -EPERM;

		else

			ifs_test_core(cpu, dev);

		break;

	case IFS_TYPE_ARRAY_BIST:

		ifs_array_test_core(cpu, dev);

		break;

	default:

		return -EINVAL;

		ret = -EINVAL;

	}

out:

	cpus_read_unlock();