commit 87d3aa28f345bea77c396855fa5d5fec4c24461f upstream.
When a new control group is created __init_one_rdt_domain() walks all
the other closids to calculate the sets of used and unused bits.
If it discovers a pseudo_locksetup group, it breaks out of the loop. This
means any later closid doesn't get its used bits added to used_b. These
bits will then get set in unused_b, and added to the new control group's
configuration, even if they were marked as exclusive for a later closid.
When encountering a pseudo_locksetup group, we should continue. This is
because "a resource group enters 'pseudo-locked' mode after the schemata is
written while the resource group is in 'pseudo-locksetup' mode." When we
find a pseudo_locksetup group, its configuration is expected to be
overwritten, we can skip it.
Fixes: dfe9674b04ff6 ("x86/intel_rdt: Enable entering of pseudo-locksetup mode")
Signed-off-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: H Peter Avin <hpa@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20190603172531.178830-1-james.morse@xxxxxxx
[Dropped comment due to lack of space]
Signed-off-by: James Morse <james.morse@xxxxxxx>
---
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 85212a32b54d..c51b56e29948 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2556,7 +2556,7 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
if (closid_allocated(i) && i != closid) {
mode = rdtgroup_mode_by_closid(i);
if (mode == RDT_MODE_PSEUDO_LOCKSETUP)
- break;
+ continue;
/*
* If CDP is active include peer
* domain's usage to ensure there
--
2.20.1
