From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@suse.com>
Subject: [PATCH] x86/HAP: avoid using bogus/misleading locking
Date: Mon, 29 May 2017 06:37:37 -0600
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hap_teardown() unconditionally releases the paging lock and is always
being called without the lock held: Lock acquire should then be
unconditional too.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
While this is only a cosmetic change afaict I would still like to
explore whether to include this in 4.9.

--- a/xen/arch/x86/mm/hap/hap.c
+++ b/xen/arch/x86/mm/hap/hap.c
@@ -576,8 +576,7 @@ void hap_teardown(struct domain *d, bool
     ASSERT(d->is_dying);
     ASSERT(d !=3D current->domain);
=20
-    if ( !paging_locked_by_me(d) )
-        paging_lock(d); /* Keep various asserts happy */
+    paging_lock(d); /* Keep various asserts happy */
=20
     if ( paging_mode_enabled(d) )
     {




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x86/HAP: avoid using bogus/misleading locking=0A=0Ahap_teardown() =
unconditionally releases the paging lock and is always=0Abeing called =
without the lock held: Lock acquire should then be=0Aunconditional =
too.=0A=0ASigned-off-by: Jan Beulich <jbeulich@suse.com>=0A---=0AWhile =
this is only a cosmetic change afaict I would still like to=0Aexplore =
whether to include this in 4.9.=0A=0A--- a/xen/arch/x86/mm/hap/hap.c=0A+++ =
b/xen/arch/x86/mm/hap/hap.c=0A@@ -576,8 +576,7 @@ void hap_teardown(struct =
domain *d, bool=0A     ASSERT(d->is_dying);=0A     ASSERT(d !=3D current->d=
omain);=0A =0A-    if ( !paging_locked_by_me(d) )=0A-        paging_lock(d)=
; /* Keep various asserts happy */=0A+    paging_lock(d); /* Keep various =
asserts happy */=0A =0A     if ( paging_mode_enabled(d) )=0A     {=0A
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