From: Palmer Dabbelt palmer@rivosinc.com
[ Upstream commit f2913d006fcdb61719635e093d1b5dd0dafecac7 ]
I don't think we can actually die() without a regs pointer, but the compiler was warning about a NULL check after a dereference. It seems prudent to just avoid the possibly-NULL dereference, given that when die()ing the system is already toast so who knows how we got there.
Reported-by: kernel test robot lkp@intel.com Reported-by: Dan Carpenter dan.carpenter@oracle.com Reviewed-by: Conor Dooley conor.dooley@microchip.com Link: https://lore.kernel.org/r/20220920200037.6727-1-palmer@rivosinc.com Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Stable-dep-of: 130aee3fd998 ("riscv: Avoid enabling interrupts in die()") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/kernel/traps.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 23fe03ca7ec7b..bc6b30f3add83 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -31,6 +31,7 @@ void die(struct pt_regs *regs, const char *str) { static int die_counter; int ret; + long cause;
oops_enter();
@@ -40,11 +41,13 @@ void die(struct pt_regs *regs, const char *str)
pr_emerg("%s [#%d]\n", str, ++die_counter); print_modules(); - show_regs(regs); + if (regs) + show_regs(regs);
- ret = notify_die(DIE_OOPS, str, regs, 0, regs->cause, SIGSEGV); + cause = regs ? regs->cause : -1; + ret = notify_die(DIE_OOPS, str, regs, 0, cause, SIGSEGV);
- if (regs && kexec_should_crash(current)) + if (kexec_should_crash(current)) crash_kexec(regs);
bust_spinlocks(0);