On Thu, Jun 09, 2005 at 10:37:49AM -0700, Ton Truong wrote:
> I see that in the rc5 update, MIPS codes have now dropped
> sc_sigset[4] from struct sigcontext, defined in asm-mips/sigcontext.h. I'd
> appreciate it if someone provide a brief summary of what needs to be changed
> for strace to compile or where I can find an strace port that work with the
> new MIPS codes?
>
> Much appreciated.
Things turned a little more complicated, unfortunately. So the recent
support for the DSP ASE broke compilation of some code in strace that
wasn't functioning anyway. Fixing that did collide with a RM9000 bug
workaround ... So this is something that hopefully will work for any
processor and re-establish binary compatibility with debuggers.
Strace will need a separate patch.
Comments?
Ralf
arch/mips/kernel/signal-common.h | 34 ++++++++-
arch/mips/kernel/signal.c | 59 +++++++----------
arch/mips/kernel/signal32.c | 16 ++++
arch/mips/kernel/signal_n32.c | 32 +++------
include/asm-mips/cpu-features.h | 11 ---
include/asm-mips/mach-ja/cpu-feature-overrides.h | 6 -
include/asm-mips/mach-ocelot3/cpu-feature-overrides.h | 6 -
include/asm-mips/mach-yosemite/cpu-feature-overrides.h | 6 -
include/asm-mips/war.h | 14 ++++
9 files changed, 98 insertions(+), 86 deletions(-)
Index: linux-qa/include/asm-mips/mach-ocelot3/cpu-feature-overrides.h
===================================================================
--- linux-qa.orig/include/asm-mips/mach-ocelot3/cpu-feature-overrides.h 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/include/asm-mips/mach-ocelot3/cpu-feature-overrides.h 2005-06-14 14:25:12.000000000 +0100
@@ -40,10 +40,4 @@
#define cpu_icache_line_size() 32
#define cpu_scache_line_size() 32
-/*
- * On the RM9000 we need to ensure that I-cache lines being fetches only
- * contain valid instructions are funny things will happen.
- */
-#define PLAT_TRAMPOLINE_STUFF_LINE 32UL
-
#endif /* __ASM_MACH_JA_CPU_FEATURE_OVERRIDES_H */
Index: linux-qa/include/asm-mips/cpu-features.h
===================================================================
--- linux-qa.orig/include/asm-mips/cpu-features.h 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/include/asm-mips/cpu-features.h 2005-06-14 14:25:12.000000000 +0100
@@ -109,17 +109,6 @@
#define cpu_has_dsp (cpu_data[0].ases & MIPS_ASE_DSP)
#endif
-/*
- * Certain CPUs may throw bizarre exceptions if not the whole cacheline
- * contains valid instructions. For these we ensure proper alignment of
- * signal trampolines and pad them to the size of a full cache lines with
- * nops. This is also used in structure definitions so can't be a test macro
- * like the others.
- */
-#ifndef PLAT_TRAMPOLINE_STUFF_LINE
-#define PLAT_TRAMPOLINE_STUFF_LINE 0UL
-#endif
-
#ifdef CONFIG_MIPS32
# ifndef cpu_has_nofpuex
# define cpu_has_nofpuex (cpu_data[0].options & MIPS_CPU_NOFPUEX)
Index: linux-qa/include/asm-mips/mach-yosemite/cpu-feature-overrides.h
===================================================================
--- linux-qa.orig/include/asm-mips/mach-yosemite/cpu-feature-overrides.h 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/include/asm-mips/mach-yosemite/cpu-feature-overrides.h 2005-06-14 14:25:12.000000000 +0100
@@ -37,10 +37,4 @@
#define cpu_icache_line_size() 32
#define cpu_scache_line_size() 32
-/*
- * On the RM9000 we need to ensure that I-cache lines being fetches only
- * contain valid instructions are funny things will happen.
- */
-#define PLAT_TRAMPOLINE_STUFF_LINE 32UL
-
#endif /* __ASM_MACH_YOSEMITE_CPU_FEATURE_OVERRIDES_H */
Index: linux-qa/arch/mips/kernel/signal_n32.c
===================================================================
--- linux-qa.orig/arch/mips/kernel/signal_n32.c 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/arch/mips/kernel/signal_n32.c 2005-06-14 15:47:37.000000000 +0100
@@ -15,6 +15,8 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
+#include <linux/cache.h>
+#include <linux/sched.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
@@ -36,6 +38,7 @@
#include <asm/system.h>
#include <asm/fpu.h>
#include <asm/cpu-features.h>
+#include <asm/war.h>
#include "signal-common.h"
@@ -62,17 +65,18 @@
sigset_t uc_sigmask; /* mask last for extensibility */
};
-#if PLAT_TRAMPOLINE_STUFF_LINE
-#define __tramp __attribute__((aligned(PLAT_TRAMPOLINE_STUFF_LINE)))
-#else
-#define __tramp
-#endif
-
struct rt_sigframe_n32 {
u32 rs_ass[4]; /* argument save space for o32 */
- u32 rs_code[2] __tramp; /* signal trampoline */
- struct siginfo rs_info __tramp;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 rs_pad[2];
+#else
+ u32 rs_code[2]; /* signal trampoline */
+#endif
+ struct siginfo rs_info;
struct ucontextn32 rs_uc;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */
+#endif
};
save_static_function(sysn32_rt_sigreturn);
@@ -137,17 +141,7 @@
if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
goto give_sigsegv;
- /*
- * Set up the return code ...
- *
- * li v0, __NR_rt_sigreturn
- * syscall
- */
- if (PLAT_TRAMPOLINE_STUFF_LINE)
- __clear_user(frame->rs_code, PLAT_TRAMPOLINE_STUFF_LINE);
- err |= __put_user(0x24020000 + __NR_N32_rt_sigreturn, frame->rs_code + 0);
- err |= __put_user(0x0000000c , frame->rs_code + 1);
- flush_cache_sigtramp((unsigned long) frame->rs_code);
+ install_sigtramp(frame->rs_code, __NR_N32_rt_sigreturn);
/* Create siginfo. */
err |= copy_siginfo_to_user(&frame->rs_info, info);
Index: linux-qa/arch/mips/kernel/signal.c
===================================================================
--- linux-qa.orig/arch/mips/kernel/signal.c 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/arch/mips/kernel/signal.c 2005-06-14 16:37:36.000000000 +0100
@@ -8,6 +8,7 @@
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#include <linux/config.h>
+#include <linux/cache.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/personality.h>
@@ -30,6 +31,7 @@
#include <asm/uaccess.h>
#include <asm/ucontext.h>
#include <asm/cpu-features.h>
+#include <asm/war.h>
#include "signal-common.h"
@@ -157,26 +159,39 @@
return do_sigaltstack(uss, uoss, usp);
}
-#if PLAT_TRAMPOLINE_STUFF_LINE
-#define __tramp __attribute__((aligned(PLAT_TRAMPOLINE_STUFF_LINE)))
-#else
-#define __tramp
-#endif
-
+/*
+ * Horribly complicated - with the bloody RM9000 workarounds enabled
+ * the signal trampolines is moving to the end of the structure so we can
+ * increase the alignment without breaking software compatibility.
+ */
#ifdef CONFIG_TRAD_SIGNALS
struct sigframe {
u32 sf_ass[4]; /* argument save space for o32 */
- u32 sf_code[2] __tramp; /* signal trampoline */
- struct sigcontext sf_sc __tramp;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 sf_pad[2];
+#else
+ u32 sf_code[2]; /* signal trampoline */
+#endif
+ struct sigcontext sf_sc;
sigset_t sf_mask;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */
+#endif
};
#endif
struct rt_sigframe {
u32 rs_ass[4]; /* argument save space for o32 */
- u32 rs_code[2] __tramp; /* signal trampoline */
- struct siginfo rs_info __tramp;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 rs_pad[2];
+#else
+ u32 rs_code[2]; /* signal trampoline */
+#endif
+ struct siginfo rs_info;
struct ucontext rs_uc;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */
+#endif
};
#ifdef CONFIG_TRAD_SIGNALS
@@ -273,17 +288,7 @@
if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
goto give_sigsegv;
- /*
- * Set up the return code ...
- *
- * li v0, __NR_sigreturn
- * syscall
- */
- if (PLAT_TRAMPOLINE_STUFF_LINE)
- __clear_user(frame->sf_code, PLAT_TRAMPOLINE_STUFF_LINE);
- err |= __put_user(0x24020000 + __NR_sigreturn, frame->sf_code + 0);
- err |= __put_user(0x0000000c , frame->sf_code + 1);
- flush_cache_sigtramp((unsigned long) frame->sf_code);
+ install_sigtramp(frame->sf_code, __NR_sigreturn);
err |= setup_sigcontext(regs, &frame->sf_sc);
err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
@@ -329,17 +334,7 @@
if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
goto give_sigsegv;
- /*
- * Set up the return code ...
- *
- * li v0, __NR_rt_sigreturn
- * syscall
- */
- if (PLAT_TRAMPOLINE_STUFF_LINE)
- __clear_user(frame->rs_code, PLAT_TRAMPOLINE_STUFF_LINE);
- err |= __put_user(0x24020000 + __NR_rt_sigreturn, frame->rs_code + 0);
- err |= __put_user(0x0000000c , frame->rs_code + 1);
- flush_cache_sigtramp((unsigned long) frame->rs_code);
+ install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
/* Create siginfo. */
err |= copy_siginfo_to_user(&frame->rs_info, info);
Index: linux-qa/include/asm-mips/mach-ja/cpu-feature-overrides.h
===================================================================
--- linux-qa.orig/include/asm-mips/mach-ja/cpu-feature-overrides.h 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/include/asm-mips/mach-ja/cpu-feature-overrides.h 2005-06-14 14:25:12.000000000 +0100
@@ -37,10 +37,4 @@
#define cpu_icache_line_size() 32
#define cpu_scache_line_size() 32
-/*
- * On the RM9000 we need to ensure that I-cache lines being fetches only
- * contain valid instructions are funny things will happen.
- */
-#define PLAT_TRAMPOLINE_STUFF_LINE 32UL
-
#endif /* __ASM_MACH_JA_CPU_FEATURE_OVERRIDES_H */
Index: linux-qa/arch/mips/kernel/signal-common.h
===================================================================
--- linux-qa.orig/arch/mips/kernel/signal-common.h 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/arch/mips/kernel/signal-common.h 2005-06-14 14:25:12.000000000 +0100
@@ -160,7 +160,7 @@
static inline void *
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
{
- unsigned long sp, almask;
+ unsigned long sp;
/* Default to using normal stack */
sp = regs->regs[29];
@@ -176,10 +176,32 @@
if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
sp = current->sas_ss_sp + current->sas_ss_size;
- if (PLAT_TRAMPOLINE_STUFF_LINE)
- almask = ~(PLAT_TRAMPOLINE_STUFF_LINE - 1);
- else
- almask = ALMASK;
+ return (void *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? 32 : ALMASK));
+}
+
+static inline int install_sigtramp(unsigned int __user *tramp,
+ unsigned int syscall)
+{
+ int err;
+
+ /*
+ * Set up the return code ...
+ *
+ * li v0, __NR__foo_sigreturn
+ * syscall
+ */
+
+ err |= __put_user(0x24020000 + syscall, tramp + 0);
+ err |= __put_user(0x0000000c , tramp + 1);
+ if (ICACHE_REFILLS_WORKAROUND_WAR) {
+ err |= __put_user(0, tramp + 2);
+ err |= __put_user(0, tramp + 3);
+ err |= __put_user(0, tramp + 4);
+ err |= __put_user(0, tramp + 5);
+ err |= __put_user(0, tramp + 6);
+ err |= __put_user(0, tramp + 7);
+ }
+ flush_cache_sigtramp((unsigned long) tramp);
- return (void *)((sp - frame_size) & almask);
+ return err;
}
Index: linux-qa/include/asm-mips/war.h
===================================================================
--- linux-qa.orig/include/asm-mips/war.h 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/include/asm-mips/war.h 2005-06-14 14:25:12.000000000 +0100
@@ -177,6 +177,17 @@
#endif
/*
+ * The RM9000 has a bug (though PMC-Sierra opposes it being called that)
+ * where invalid instructions in the same I-cache line worth of instructions
+ * being fetched may case spurious exceptions.
+ */
+#if defined(CONFIG_MOMENCO_JAGUAR_ATX) || defined(CONFIG_MOMENCO_OCELOT_3) || \
+ defined(CONFIG_PMC_YOSEMITE)
+#define ICACHE_REFILLS_WORKAROUND_WAR 1
+#endif
+
+
+/*
* ON the R10000 upto version 2.6 (not sure about 2.7) there is a bug that
* may cause ll / sc and lld / scd sequences to execute non-atomically.
*/
@@ -187,6 +198,9 @@
/*
* Workarounds default to off
*/
+#ifndef ICACHE_REFILLS_WORKAROUND_WAR
+#define ICACHE_REFILLS_WORKAROUND_WAR 0
+#endif
#ifndef R4600_V1_INDEX_ICACHEOP_WAR
#define R4600_V1_INDEX_ICACHEOP_WAR 0
#endif
Index: linux-qa/arch/mips/kernel/signal32.c
===================================================================
--- linux-qa.orig/arch/mips/kernel/signal32.c 2005-06-14 12:53:28.000000000 +0100
+++ linux-qa/arch/mips/kernel/signal32.c 2005-06-14 15:47:24.000000000 +0100
@@ -7,6 +7,7 @@
* Copyright (C) 1994 - 2000 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
+#include <linux/cache.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
@@ -30,6 +31,7 @@
#include <asm/ucontext.h>
#include <asm/system.h>
#include <asm/fpu.h>
+#include <asm/war.h>
#define SI_PAD_SIZE32 ((SI_MAX_SIZE/sizeof(int)) - 3)
@@ -392,16 +394,30 @@
struct sigframe {
u32 sf_ass[4]; /* argument save space for o32 */
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 sf_pad[2];
+#else
u32 sf_code[2]; /* signal trampoline */
+#endif
struct sigcontext32 sf_sc;
sigset_t sf_mask;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */
+#endif
};
struct rt_sigframe32 {
u32 rs_ass[4]; /* argument save space for o32 */
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 rs_pad[2];
+#else
u32 rs_code[2]; /* signal trampoline */
+#endif
compat_siginfo_t rs_info;
struct ucontext32 rs_uc;
+#if ICACHE_REFILLS_WORKAROUND_WAR
+ u32 rs_code[8] __attribute__((aligned(32))); /* signal trampoline */
+#endif
};
int copy_siginfo_to_user32(compat_siginfo_t *to, siginfo_t *from)
