This is a note to let you know that I've just added the patch titled
x86/hyper-v: Check for VP_INVAL in hyperv_flush_tlb_others()
to the 4.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-hyper-v-check-for-vp_inval-in-hyperv_flush_tlb_others.patch
and it can be found in the queue-4.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From 110d2a7fc39725d2c29d2fede4f34a35a4f98882 Mon Sep 17 00:00:00 2001
From: Vitaly Kuznetsov <[email protected]>
Date: Mon, 9 Jul 2018 19:40:12 +0200
Subject: x86/hyper-v: Check for VP_INVAL in hyperv_flush_tlb_others()
From: Vitaly Kuznetsov <[email protected]>
commit 110d2a7fc39725d2c29d2fede4f34a35a4f98882 upstream.
Commit 1268ed0c474a ("x86/hyper-v: Fix the circular dependency in IPI
enlightenment") pre-filled hv_vp_index with VP_INVAL so it is now
(theoretically) possible to observe hv_cpu_number_to_vp_number()
returning VP_INVAL. We need to check for that in hyperv_flush_tlb_others().
Not checking for VP_INVAL on the first call site where we do
if (hv_cpu_number_to_vp_number(cpumask_last(cpus)) >= 64)
goto do_ex_hypercall;
is OK, in case we're eligible for non-ex hypercall we'll catch the
issue later in for_each_cpu() cycle and in case we'll be doing ex-
hypercall cpumask_to_vpset() will fail.
It would be nice to change hv_cpu_number_to_vp_number() return
value's type to 'u32' but this will likely be a bigger change as
all call sites need to be checked first.
Fixes: 1268ed0c474a ("x86/hyper-v: Fix the circular dependency in IPI
enlightenment")
Signed-off-by: Vitaly Kuznetsov <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Michael Kelley <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: "Michael Kelley (EOSG)" <[email protected]>
Cc: [email protected]
Cc: "H. Peter Anvin" <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
arch/x86/hyperv/mmu.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/arch/x86/hyperv/mmu.c
+++ b/arch/x86/hyperv/mmu.c
@@ -95,6 +95,11 @@ static void hyperv_flush_tlb_others(cons
} else {
for_each_cpu(cpu, cpus) {
vcpu = hv_cpu_number_to_vp_number(cpu);
+ if (vcpu == VP_INVAL) {
+ local_irq_restore(flags);
+ goto do_native;
+ }
+
if (vcpu >= 64)
goto do_native;
Patches currently in stable-queue which might be from [email protected] are
queue-4.18/x86-hyper-v-check-for-vp_inval-in-hyperv_flush_tlb_others.patch
_______________________________________________
devel mailing list
[email protected]
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
