s390: fix system call restart after inferior call

commit dbbfe487e5f3fc00c9fe5207d63309859704d12f upstream.

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.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 4d5e6f8a7978cb005d0ae15fe3d1837175f285d1..32bb7bf29397f6323da132c127fb8b8a1b063669 100644 (file)
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -265,6 +265,7 @@ 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 4c17eece707eb94d0b08c55b63a25b7788fb0c56..2e3befddeceed74b43436bf79b10fbfeecae95e6 100644 (file)
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -293,6 +293,7 @@ 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