From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit cc5277fe66cf3ad68f41f1c539b2ef0d5e432974 ]
The callers don't expect *d_cdp to be set to an error pointer, they only check for NULL. This leads to a static checker warning:
arch/x86/kernel/cpu/resctrl/rdtgroup.c:2648 __init_one_rdt_domain() warn: 'd_cdp' could be an error pointer
This would not trigger a bug in this specific case because __init_one_rdt_domain() calls it with a valid domain that would not have a negative id and thus not trigger the return of the ERR_PTR(). If this was a negative domain id then the call to rdt_find_domain() in domain_add_cpu() would have returned the ERR_PTR() much earlier and the creation of the domain with an invalid id would have been prevented.
Even though a bug is not triggered currently the right and safe thing to do is to set the pointer to NULL because that is what can be checked for when the caller is handling the CDP and non-CDP cases.
Fixes: 52eb74339a62 ("x86/resctrl: Fix rdt_find_domain() return value and checks") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Borislav Petkov bp@suse.de Acked-by: Reinette Chatre reinette.chatre@intel.com Acked-by: Fenghua Yu fenghua.yu@intel.com Link: https://lkml.kernel.org/r/20200602193611.GA190851@mwanda Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 5a359d9fcc055..29a3878ab3c01 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -1117,6 +1117,7 @@ static int rdt_cdp_peer_get(struct rdt_resource *r, struct rdt_domain *d, _d_cdp = rdt_find_domain(_r_cdp, d->id, NULL); if (WARN_ON(IS_ERR_OR_NULL(_d_cdp))) { _r_cdp = NULL; + _d_cdp = NULL; ret = -EINVAL; }