@@ -1001,9 +1001,8 @@ ENTRY(fast_syscall_xtensa)
movi a7, 4 # sizeof(unsigned int)
access_ok a3, a7, a0, a2, .Leac # a0: scratch reg, a2: sp
- addi a6, a6, -1 # assuming SYS_XTENSA_ATOMIC_SET = 1
- _bgeui a6, SYS_XTENSA_COUNT - 1, .Lill
- _bnei a6, SYS_XTENSA_ATOMIC_CMP_SWP - 1, .Lnswp
+ _bgeui a6, SYS_XTENSA_COUNT, .Lill
+ _bnei a6, SYS_XTENSA_ATOMIC_CMP_SWP, .Lnswp
/* Fall through for ATOMIC_CMP_SWP. */
@@ -1015,27 +1014,26 @@ TRY s32i a5, a3, 0 # different, modify value
l32i a7, a2, PT_AREG7 # restore a7
l32i a0, a2, PT_AREG0 # restore a0
movi a2, 1 # and return 1
- addi a6, a6, 1 # restore a6 (really necessary?)
rfe
1: l32i a7, a2, PT_AREG7 # restore a7
l32i a0, a2, PT_AREG0 # restore a0
movi a2, 0 # return 0 (note that we cannot set
- addi a6, a6, 1 # restore a6 (really necessary?)
rfe
.Lnswp: /* Atomic set, add, and exg_add. */
TRY l32i a7, a3, 0 # orig
+ addi a6, a6, -SYS_XTENSA_ATOMIC_SET
add a0, a4, a7 # + arg
moveqz a0, a4, a6 # set
+ addi a6, a6, SYS_XTENSA_ATOMIC_SET
TRY s32i a0, a3, 0 # write new value
mov a0, a2
mov a2, a7
l32i a7, a0, PT_AREG7 # restore a7
l32i a0, a0, PT_AREG0 # restore a0
- addi a6, a6, 1 # restore a6 (really necessary?)
rfe
CATCH
@@ -1044,7 +1042,7 @@ CATCH
movi a2, -EFAULT
rfe
-.Lill: l32i a7, a2, PT_AREG0 # restore a7
+.Lill: l32i a7, a2, PT_AREG7 # restore a7
l32i a0, a2, PT_AREG0 # restore a0
movi a2, -EINVAL
rfe
This is a note to let you know that I have just added a patch titled xtensa: fix a6 and a7 handling in fast_syscall_xtensa to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.8. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From f2db8d9a7fcd2ede79ac920cfda35969603f818e Mon Sep 17 00:00:00 2001 From: Max Filippov <jcmvbkbc@gmail.com> Date: Thu, 31 Jul 2014 22:40:57 +0400 Subject: xtensa: fix a6 and a7 handling in fast_syscall_xtensa commit d1b6ba82a50cecf94be540a3a153aa89d97511a0 upstream. Remove restoring a6 on some return paths and instead modify and restore it in a single place, using symbolic name. Correctly restore a7 from PT_AREG7 in case of illegal a6 value. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- arch/xtensa/kernel/entry.S | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) -- 1.9.1