Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a720b2dd authored by Srivatsa S. Bhat's avatar Srivatsa S. Bhat Committed by Borislav Petkov
Browse files

x86, intel_cacheinfo: Fix error return code in amd_set_l3_disable_slot() 



If the L3 disable slot is already in use, return -EEXIST instead of
-EINVAL. The caller, store_cache_disable(), checks this return value to
print an appropriate warning.

Also, we want to signal with -EEXIST that the current index we're
disabling has actually been already disabled on the node:

$ echo 12 > /sys/devices/system/cpu/cpu3/cache/index3/cache_disable_0
$ echo 12 > /sys/devices/system/cpu/cpu3/cache/index3/cache_disable_0
-bash: echo: write error: File exists
$ echo 12 > /sys/devices/system/cpu/cpu3/cache/index3/cache_disable_1
-bash: echo: write error: File exists
$ echo 12 > /sys/devices/system/cpu/cpu5/cache/index3/cache_disable_1
-bash: echo: write error: File exists

The old code would say

-bash: echo: write error: Invalid argument

for disable slot 1 when playing the example above with no output in
dmesg, which is clearly misleading.

Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120419070053.GB16645@elgon.mountain


[Boris: add testing for the other index too]
Signed-off-by: default avatarBorislav Petkov <borislav.petkov@amd.com>
parent e816b57a

arch/x86/kernel/cpu/intel_cacheinfo.c

+4 −4
Original line number Diff line number Diff line
@@ -433,14 +433,14 @@ int amd_set_l3_disable_slot(struct amd_northbridge *nb, int cpu, unsigned slot, 
	/*  check if @slot is already used or the index is already disabled */

	ret = amd_get_l3_disable_slot(nb, slot);

	if (ret >= 0)

		return -EINVAL;

		return -EEXIST;



	if (index > nb->l3_cache.indices)

		return -EINVAL;



	/* check whether the other slot has disabled the same index already */

	if (index == amd_get_l3_disable_slot(nb, !slot))

		return -EINVAL;

		return -EEXIST;



	amd_l3_disable_index(nb, cpu, slot, index);
@@ -468,7 +468,7 @@ static ssize_t store_cache_disable(struct _cpuid4_info *this_leaf, 
	err = amd_set_l3_disable_slot(this_leaf->base.nb, cpu, slot, val);

	if (err) {

		if (err == -EEXIST)

			printk(KERN_WARNING "L3 disable slot %d in use!\n",

			pr_warning("L3 slot %d in use/index already disabled!\n",

				   slot);

		return err;

	}