s390: fix system call restart after inferior call

Git commit 616498813b11ffef "s390: system call path micro optimization"
introduced a regression in regard to system call restarting and inferior
function calls via the ptrace interface. The pointer to the system call
table needs to be loaded in sysc_sigpending if do_signal returns with
TIF_SYSCALl set after it restored a system call context.

Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index cc30d1f..0dc2b6d 100644 (file)
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -266,6 +266,7 @@ sysc_sigpending:
        tm      __TI_flags+3(%r12),_TIF_SYSCALL
        jno     sysc_return
        lm      %r2,%r7,__PT_R2(%r11)   # load svc arguments
+       l       %r10,__TI_sysc_table(%r12)      # 31 bit system call table
        xr      %r8,%r8                 # svc 0 returns -ENOSYS
        clc     __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2)
        jnl     sysc_nr_ok              # invalid svc number -> do svc 0

diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 2b2188b..e5b43c9 100644 (file)
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -297,6 +297,7 @@ sysc_sigpending:
        tm      __TI_flags+7(%r12),_TIF_SYSCALL
        jno     sysc_return
        lmg     %r2,%r7,__PT_R2(%r11)   # load svc arguments
+       lg      %r10,__TI_sysc_table(%r12)      # address of system call table
        lghi    %r8,0                   # svc 0 returns -ENOSYS
        llgh    %r1,__PT_INT_CODE+2(%r11)       # load new svc number
        cghi    %r1,NR_syscalls