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authorPaul Burton <paul.burton@mips.com>2018-06-14 10:20:54 -0700
committerPaul Burton <paul.burton@mips.com>2018-06-19 21:13:56 -0700
commit9bcf53598dfe1bd8caaf8e03738d3cc51d45904e (patch)
treeee25419bb284148763c5a9cd2ae30424d006ca44 /arch/mips
parentMIPS: Add support for restartable sequences (diff)
downloadlinux-dev-9bcf53598dfe1bd8caaf8e03738d3cc51d45904e.tar.xz
linux-dev-9bcf53598dfe1bd8caaf8e03738d3cc51d45904e.zip
MIPS: Add syscall detection for restartable sequences
Syscalls are not allowed inside restartable sequences, so add a call to rseq_syscall() at the very beginning of the system call exit path when CONFIG_DEBUG_RSEQ=y. This will help us to detect whether there is a syscall issued erroneously inside a restartable sequence. Signed-off-by: Paul Burton <paul.burton@mips.com> Reviewed-by: James Hogan <jhogan@kernel.org> Patchwork: https://patchwork.linux-mips.org/patch/19522/ Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Diffstat (limited to 'arch/mips')
-rw-r--r--arch/mips/kernel/entry.S8
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/mips/kernel/entry.S b/arch/mips/kernel/entry.S
index 38a302919e6b..d7de8adcfcc8 100644
--- a/arch/mips/kernel/entry.S
+++ b/arch/mips/kernel/entry.S
@@ -79,6 +79,10 @@ FEXPORT(ret_from_fork)
jal schedule_tail # a0 = struct task_struct *prev
FEXPORT(syscall_exit)
+#ifdef CONFIG_DEBUG_RSEQ
+ move a0, sp
+ jal rseq_syscall
+#endif
local_irq_disable # make sure need_resched and
# signals dont change between
# sampling and return
@@ -141,6 +145,10 @@ work_notifysig: # deal with pending signals and
j resume_userspace_check
FEXPORT(syscall_exit_partial)
+#ifdef CONFIG_DEBUG_RSEQ
+ move a0, sp
+ jal rseq_syscall
+#endif
local_irq_disable # make sure need_resched doesn't
# change between and return
LONG_L a2, TI_FLAGS($28) # current->work