The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 87d3aa28f345bea77c396855fa5d5fec4c24461f Mon Sep 17 00:00:00 2001
From: James Morse <james.morse@xxxxxxx>
Date: Mon, 3 Jun 2019 18:25:31 +0100
Subject: [PATCH] x86/resctrl: Don't stop walking closids when a locksetup
group is found
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
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 333c177a2471..869cbef5da81 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2542,7 +2542,12 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct rdt_resource *r,
if (closid_allocated(i) && i != closid) {
mode = rdtgroup_mode_by_closid(i);
if (mode == RDT_MODE_PSEUDO_LOCKSETUP)
- break;
+ /*
+ * ctrl values for locksetup aren't relevant
+ * until the schemata is written, and the mode
+ * becomes RDT_MODE_PSEUDO_LOCKED.
+ */
+ continue;
/*
* If CDP is active include peer domain's
* usage to ensure there is no overlap
