From 616cb2f4b141852cac3dfffe8354c8bf19e9999d Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 22 Jun 2023 14:39:45 +0100 Subject: [PATCH] arm64/signal: Restore TPIDR2 register rather than memory state Currently when restoring the TPIDR2 signal context we set the new value from the signal frame in the thread data structure but not the register, following the pattern for the rest of the data we are restoring. This does not work in the case of TPIDR2, the register always has the value for the current task. This means that either we return to userspace and ignore the new value or we context switch and save the register value on top of the newly restored value. Load the value from the signal context into the register instead. Fixes: 39e54499280f ("arm64/signal: Include TPIDR2 in the signal context") Signed-off-by: Mark Brown Cc: # 6.3.x Link: https://lore.kernel.org/r/20230621-arm64-fix-tpidr2-signal-restore-v2-1-c8e8fcc10302@kernel.org Signed-off-by: Catalin Marinas --- arch/arm64/kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index 2cfc810d0a5b1..10b407672c427 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -398,7 +398,7 @@ static int restore_tpidr2_context(struct user_ctxs *user) __get_user_error(tpidr2_el0, &user->tpidr2->tpidr2, err); if (!err) - current->thread.tpidr2_el0 = tpidr2_el0; + write_sysreg_s(tpidr2_el0, SYS_TPIDR2_EL0); return err; } -- 2.30.2