According to create_thread(3): "The new thread does not inherit the creating thread's alternate signal stack". Since commit f9a3879a (Fix sigaltstack corruption among cloned threads), current->sas_ss_size is set to 0 for cloned processes sharing VM with their parent. Don't use the (nonexistent) alternate signal stack in this case. This has been broken since commit 29c4dfd9 ([XTENSA] Remove non-rt signal handling).
Fixes the SA_ONSTACK part of the nptl/tst-cancel20 test from uClibc. Cc: <[email protected]> Signed-off-by: Baruch Siach <[email protected]> --- v2: Use sas_ss_flags() as suggested by Max Filippov. Reword commit message. arch/xtensa/kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c index 718eca1..98b67d5 100644 --- a/arch/xtensa/kernel/signal.c +++ b/arch/xtensa/kernel/signal.c @@ -341,7 +341,7 @@ static int setup_frame(int sig, struct k_sigaction *ka, siginfo_t *info, sp = regs->areg[1]; - if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp)) { + if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && sas_ss_flags(sp) == 0) { sp = current->sas_ss_sp + current->sas_ss_size; } -- 1.8.4.rc3 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
