[PATCH AUTOSEL 5.18 06/53] arm64: Do not forget syscall when starting a new thread.

Sasha Levin
2022-08-08T01:40:03Z

From: Francis Laniel <flaniel@linux.microsoft.com>

[ Upstream commit de6921856f99c11d3986c6702d851e1328d4f7f6 ]

Enable tracing of the execve*() system calls with the
syscalls:sys_exit_execve tracepoint by removing the call to
forget_syscall() when starting a new thread and preserving the value of
regs->syscallno across exec.

Signed-off-by: Francis Laniel <flaniel@linux.microsoft.com>
Link: https://lore.kernel.org/r/20220608162447.666494-2-flaniel@linux.microsoft.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arm64/include/asm/processor.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 6b1a12c23fe7..7058bf047fa5 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -250,8 +250,9 @@ void tls_preserve_current_state(void);

static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
{
+ s32 previous_syscall = regs->syscallno;
memset(regs, 0, sizeof(*regs));
- forget_syscall(regs);
+ regs->syscallno = previous_syscall;
regs->pc = pc;

if (system_uses_irq_prio_masking())
--
2.35.1