From: Mark Brown broonie@kernel.org
commit 616cb2f4b141852cac3dfffe8354c8bf19e9999d upstream.
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 broonie@kernel.org Cc: stable@vger.kernel.org # 6.3.x Link: https://lore.kernel.org/r/20230621-arm64-fix-tpidr2-signal-restore-v2-1-c8e8... Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -398,7 +398,7 @@ static int restore_tpidr2_context(struct
__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; }