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[PATCH 08/21] linux-user/hppa: Document non-use of setup_sigtramp
From: |
Richard Henderson |
Subject: |
[PATCH 08/21] linux-user/hppa: Document non-use of setup_sigtramp |
Date: |
Tue, 15 Jun 2021 18:11:56 -0700 |
We cannot use a raw sigtramp page for hppa,
but must wait for full vdso support.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
linux-user/hppa/target_signal.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/linux-user/hppa/target_signal.h b/linux-user/hppa/target_signal.h
index 7f525362e9..d558119ee7 100644
--- a/linux-user/hppa/target_signal.h
+++ b/linux-user/hppa/target_signal.h
@@ -71,4 +71,18 @@ typedef struct target_sigaltstack {
/* mask for all SS_xxx flags */
#define TARGET_SS_FLAG_BITS TARGET_SS_AUTODISARM
+/*
+ * We cannot use a bare sigtramp page for hppa-linux.
+ *
+ * Unlike other guests where we use the instructions at PC to validate
+ * an offset from SP, the hppa libgcc signal frame fallback unwinding uses
+ * the PC address itself to find the frame. This is due to the fact that
+ * the hppa grows the stack upward, and the frame is of unknown size.
+ *
+ * TODO: We should be able to use a VDSO to address this, by providing
+ * proper unwind info for the sigtramp code, at which point the fallback
+ * unwinder will not be used.
+ */
+#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 0
+
#endif /* HPPA_TARGET_SIGNAL_H */
--
2.25.1
- Re: [PATCH 04/21] linux-user/arm: Implement setup_sigtramp, (continued)
[PATCH 05/21] linux-user/alpha: Implement setup_sigtramp, Richard Henderson, 2021/06/15
[PATCH 07/21] linux-user/hexagon: Implement setup_sigtramp, Richard Henderson, 2021/06/15
[PATCH 08/21] linux-user/hppa: Document non-use of setup_sigtramp,
Richard Henderson <=
[PATCH 10/21] linux-user/m68k: Implement setup_sigtramp, Richard Henderson, 2021/06/15
[PATCH 11/21] linux-user/microblaze: Implement setup_sigtramp, Richard Henderson, 2021/06/15
[PATCH 06/21] linux-user/cris: Implement setup_sigtramp, Richard Henderson, 2021/06/15
[PATCH 12/21] linux-user/mips: Implement setup_sigtramp, Richard Henderson, 2021/06/15