From: Peter Maydell <peter.mayd...@linaro.org>
In the Arm target code, when the fpa11 emulation code tells us we
need to send the guest a SIGFPE, we do this with queue_signal(), but
we are using the wrong si_type, and we aren't setting the _sifields
union members corresponding to either the si_type we are using or the
si_type we should be using.
As the existing comment notes, the kernel code for this calls the old
send_sig() function to deliver the signal. This eventually results
in the kernel's signal handling code fabricating a siginfo_t with a
SI_KERNEL code and a zero pid and uid. For QEMU this means we need
to use QEMU_SI_KILL. We already have a function for that:
force_sig() sets up the whole target_siginfo_t the way we need it.
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
Message-Id: <20210813131809.28655-4-peter.mayd...@linaro.org>
[rth: Include signal-common.h]
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
linux-user/arm/cpu_loop.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/linux-user/arm/cpu_loop.c b/linux-user/arm/cpu_loop.c
index 007752f5b7..b8ece169f9 100644
--- a/linux-user/arm/cpu_loop.c
+++ b/linux-user/arm/cpu_loop.c
@@ -22,6 +22,7 @@
#include "qemu.h"
#include "elf.h"
#include "cpu_loop-common.h"
+#include "signal-common.h"
#include "semihosting/common-semi.h"
#define get_user_code_u32(x, gaddr, env) \
@@ -266,16 +267,13 @@ static bool emulate_arm_fpa11(CPUARMState *env, uint32_t
opcode)
ts->fpa.fpsr |= raise & ~enabled;
if (raise & enabled) {
- target_siginfo_t info = { };
-
/*
* The kernel's nwfpe emulator does not pass a real si_code.
- * It merely uses send_sig(SIGFPE, current, 1).
+ * It merely uses send_sig(SIGFPE, current, 1), which results in
+ * __send_signal() filling out SI_KERNEL with pid and uid 0 (under
+ * the "SEND_SIG_PRIV" case). That's what our force_sig() does.
*/
- info.si_signo = TARGET_SIGFPE;
- info.si_code = TARGET_SI_KERNEL;
-
- queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
+ force_sig(TARGET_SIGFPE);
} else {
env->regs[15] += 4;
}
--
2.25.1
