From c8ef02b1acf0d78e909c6cbd38ed60ecc5ce52ff Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 29 Sep 2021 09:05:35 -0400 Subject: [PATCH] linux-user/hexagon: Implement setup_sigtramp MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Continue to initialize the words on the stack, as documented. However, use the off-stack trampoline. Reviewed-by: Taylor Simpson Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Richard Henderson Message-Id: <20210929130553.121567-9-richard.henderson@linaro.org> Signed-off-by: Laurent Vivier --- linux-user/hexagon/signal.c | 19 +++++++++++++++++-- linux-user/hexagon/target_signal.h | 2 ++ 2 files changed, 19 insertions(+), 2 deletions(-) diff --git a/linux-user/hexagon/signal.c b/linux-user/hexagon/signal.c index c7f0bf6b92..74e61739a0 100644 --- a/linux-user/hexagon/signal.c +++ b/linux-user/hexagon/signal.c @@ -162,6 +162,11 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, setup_ucontext(&frame->uc, env, set); tswap_siginfo(&frame->info, info); + /* + * The on-stack signal trampoline is no longer executed; + * however, the libgcc signal frame unwinding code checks + * for the presence of these two numeric magic values. + */ install_sigtramp(frame->tramp); env->gpr[HEX_REG_PC] = ka->_sa_handler; @@ -171,8 +176,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, frame_addr + offsetof(struct target_rt_sigframe, info); env->gpr[HEX_REG_R02] = frame_addr + offsetof(struct target_rt_sigframe, uc); - env->gpr[HEX_REG_LR] = - frame_addr + offsetof(struct target_rt_sigframe, tramp); + env->gpr[HEX_REG_LR] = default_rt_sigreturn; return; @@ -271,3 +275,14 @@ badframe: force_sig(TARGET_SIGSEGV); return 0; } + +void setup_sigtramp(abi_ulong sigtramp_page) +{ + uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 4 * 2, 0); + assert(tramp != NULL); + + default_rt_sigreturn = sigtramp_page; + install_sigtramp(tramp); + + unlock_user(tramp, sigtramp_page, 4 * 2); +} diff --git a/linux-user/hexagon/target_signal.h b/linux-user/hexagon/target_signal.h index 345cf1cbb8..9e0223d322 100644 --- a/linux-user/hexagon/target_signal.h +++ b/linux-user/hexagon/target_signal.h @@ -31,4 +31,6 @@ typedef struct target_sigaltstack { #include "../generic/signal.h" +#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 1 + #endif /* TARGET_SIGNAL_H */ -- 2.11.0