Mailing List Archive

commit a96d2d4355d85fc82abd0a3799978db04ee8cff3
Author: Roger Pau Monné <roger.pau@citrix.com>
AuthorDate: Tue Mar 12 12:07:07 2024 +0100
Commit: Jan Beulich <jbeulich@suse.com>
CommitDate: Tue Mar 12 12:07:07 2024 +0100

x86/mm: fix detection of last L1 entry in modify_xen_mappings_lite()

The current logic to detect when to switch to the next L1 table is incorrectly
using l2_table_offset() in order to notice when the last entry on the current
L1 table has been reached.

It should instead use l1_table_offset() to check whether the index has wrapped
to point to the first entry, and so the next L1 table should be used.

Fixes: 8676092a0f16 ('x86/livepatch: Fix livepatch application when CET is active')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 7c81558208de7858251b62f168a449be84305595
master date: 2024-03-11 11:09:42 +0000
---
xen/arch/x86/mm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
index 39544bd9f9..ab0acbfea6 100644
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -5947,7 +5947,7 @@ void init_or_livepatch modify_xen_mappings_lite(

v += 1UL << L1_PAGETABLE_SHIFT;

- if ( l2_table_offset(v) == 0 )
+ if ( l1_table_offset(v) == 0 )
break;
}

--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.18