queue-6.8/s390-entry-align-system-call-table-on-8-bytes.patch

   1 From 378ca2d2ad410a1cd5690d06b46c5e2297f4c8c0 Mon Sep 17 00:00:00 2001
   2 From: Sumanth Korikkar <sumanthk@linux.ibm.com>
   3 Date: Tue, 26 Mar 2024 18:12:13 +0100
   4 Subject: s390/entry: align system call table on 8 bytes
   5
   6 From: Sumanth Korikkar <sumanthk@linux.ibm.com>
   7
   8 commit 378ca2d2ad410a1cd5690d06b46c5e2297f4c8c0 upstream.
   9
  10 Align system call table on 8 bytes. With sys_call_table entry size
  11 of 8 bytes that eliminates the possibility of a system call pointer
  12 crossing cache line boundary.
  13
  14 Cc: stable@kernel.org
  15 Suggested-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
  16 Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
  17 Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
  18 Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20 ---
  21  arch/s390/kernel/entry.S |    1 +
  22  1 file changed, 1 insertion(+)
  23
  24 --- a/arch/s390/kernel/entry.S
  25 +++ b/arch/s390/kernel/entry.S
  26 @@ -653,6 +653,7 @@ SYM_DATA_START_LOCAL(daton_psw)
  27  SYM_DATA_END(daton_psw)
  28
  29         .section .rodata, "a"
  30 +       .balign 8
  31  #define SYSCALL(esame,emu)     .quad __s390x_ ## esame
  32  SYM_DATA_START(sys_call_table)
  33  #include "asm/syscall_table.h"