7 files changed, 127 insertions, 46 deletions

diff --git a/arch/sparc/kernel/entry.h b/arch/sparc/kernel/entry.h
index e27f8ea8656e..0c218e4c0881 100644
--- a/arch/sparc/kernel/entry.h
+++ b/arch/sparc/kernel/entry.h
@@ -42,6 +42,9 @@ extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
 extern void fpload(unsigned long *fpregs, unsigned long *fsr);
 
 #else /* CONFIG_SPARC32 */
+
+#include <asm/trap_block.h>
+
 struct popc_3insn_patch_entry {
         unsigned int    addr;
         unsigned int    insns[3];
@@ -57,6 +60,10 @@ extern struct popc_6insn_patch_entry __popc_6insn_patch,
         __popc_6insn_patch_end;
 
 extern void __init per_cpu_patch(void);
+extern void sun4v_patch_1insn_range(struct sun4v_1insn_patch_entry *,
+                                    struct sun4v_1insn_patch_entry *);
+extern void sun4v_patch_2insn_range(struct sun4v_2insn_patch_entry *,
+                                    struct sun4v_2insn_patch_entry *);
 extern void __init sun4v_patch(void);
 extern void __init boot_cpu_id_too_large(int cpu);
 extern unsigned int dcache_parity_tl1_occurred;
diff --git a/arch/sparc/kernel/module.c b/arch/sparc/kernel/module.c
index da0c6c70ccb2..e5519870c3d9 100644
--- a/arch/sparc/kernel/module.c
+++ b/arch/sparc/kernel/module.c
@@ -17,6 +17,8 @@
 #include <asm/processor.h>
 #include <asm/spitfire.h>
 
+#include "entry.h"
+
 #ifdef CONFIG_SPARC64
 
 #include <linux/jump_label.h>
@@ -203,6 +205,29 @@ int apply_relocate_add(Elf_Shdr *sechdrs,
 }
 
 #ifdef CONFIG_SPARC64
+static void do_patch_sections(const Elf_Ehdr *hdr,
+                              const Elf_Shdr *sechdrs)
+{
+        const Elf_Shdr *s, *sun4v_1insn = NULL, *sun4v_2insn = NULL;
+        char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+        for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
+                if (!strcmp(".sun4v_1insn_patch", secstrings + s->sh_name))
+                        sun4v_1insn = s;
+                if (!strcmp(".sun4v_2insn_patch", secstrings + s->sh_name))
+                        sun4v_2insn = s;
+        }
+
+        if (sun4v_1insn && tlb_type == hypervisor) {
+                void *p = (void *) sun4v_1insn->sh_addr;
+                sun4v_patch_1insn_range(p, p + sun4v_1insn->sh_size);
+        }
+        if (sun4v_2insn && tlb_type == hypervisor) {
+                void *p = (void *) sun4v_2insn->sh_addr;
+                sun4v_patch_2insn_range(p, p + sun4v_2insn->sh_size);
+        }
+}
+
 int module_finalize(const Elf_Ehdr *hdr,
                     const Elf_Shdr *sechdrs,
                     struct module *me)
@@ -210,6 +235,8 @@ int module_finalize(const Elf_Ehdr *hdr,
         /* make jump label nops */
         jump_label_apply_nops(me);
 
+        do_patch_sections(hdr, sechdrs);
+
         /* Cheetah's I-cache is fully coherent.  */
         if (tlb_type == spitfire) {
                 unsigned long va;
diff --git a/arch/sparc/kernel/setup_64.c b/arch/sparc/kernel/setup_64.c
index c965595aa7e9..a854a1c240ff 100644
--- a/arch/sparc/kernel/setup_64.c
+++ b/arch/sparc/kernel/setup_64.c
@@ -234,40 +234,50 @@ void __init per_cpu_patch(void)
         }
 }
 
-void __init sun4v_patch(void)
+void sun4v_patch_1insn_range(struct sun4v_1insn_patch_entry *start,
+                             struct sun4v_1insn_patch_entry *end)
 {
-        extern void sun4v_hvapi_init(void);
-        struct sun4v_1insn_patch_entry *p1;
-        struct sun4v_2insn_patch_entry *p2;
-
-        if (tlb_type != hypervisor)
-                return;
+        while (start < end) {
+                unsigned long addr = start->addr;
 
-        p1 = &__sun4v_1insn_patch;
-        while (p1 < &__sun4v_1insn_patch_end) {
-                unsigned long addr = p1->addr;
-
-                *(unsigned int *) (addr +  0) = p1->insn;
+                *(unsigned int *) (addr +  0) = start->insn;
                 wmb();
                 __asm__ __volatile__("flush     %0" : : "r" (addr +  0));
 
-                p1++;
+                start++;
         }
+}
 
-        p2 = &__sun4v_2insn_patch;
-        while (p2 < &__sun4v_2insn_patch_end) {
-                unsigned long addr = p2->addr;
+void sun4v_patch_2insn_range(struct sun4v_2insn_patch_entry *start,
+                             struct sun4v_2insn_patch_entry *end)
+{
+        while (start < end) {
+                unsigned long addr = start->addr;
 
-                *(unsigned int *) (addr +  0) = p2->insns[0];
+                *(unsigned int *) (addr +  0) = start->insns[0];
                 wmb();
                 __asm__ __volatile__("flush     %0" : : "r" (addr +  0));
 
-                *(unsigned int *) (addr +  4) = p2->insns[1];
+                *(unsigned int *) (addr +  4) = start->insns[1];
                 wmb();
                 __asm__ __volatile__("flush     %0" : : "r" (addr +  4));
 
-                p2++;
+                start++;
         }
+}
+
+void __init sun4v_patch(void)
+{
+        extern void sun4v_hvapi_init(void);
+
+        if (tlb_type != hypervisor)
+                return;
+
+        sun4v_patch_1insn_range(&__sun4v_1insn_patch,
+                                &__sun4v_1insn_patch_end);
+
+        sun4v_patch_2insn_range(&__sun4v_2insn_patch,
+                                &__sun4v_2insn_patch_end);
 
         sun4v_hvapi_init();
 }
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index 2caa556db86d..023b8860dc97 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c
@@ -822,21 +822,23 @@ static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs
  * want to handle. Thus you cannot kill init even with a SIGKILL even by
  * mistake.
  */
-void do_signal32(sigset_t *oldset, struct pt_regs * regs,
-                 int restart_syscall, unsigned long orig_i0)
+void do_signal32(sigset_t *oldset, struct pt_regs * regs)
 {
         struct k_sigaction ka;
+        unsigned long orig_i0;
+        int restart_syscall;
         siginfo_t info;
         int signr;
         
         signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 
-        /* If the debugger messes with the program counter, it clears
-         * the "in syscall" bit, directing us to not perform a syscall
-         * restart.
-         */
-        if (restart_syscall && !pt_regs_is_syscall(regs))
-                restart_syscall = 0;
+        restart_syscall = 0;
+        orig_i0 = 0;
+        if (pt_regs_is_syscall(regs) &&
+            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
+                restart_syscall = 1;
+                orig_i0 = regs->u_regs[UREG_G6];
+        }
 
         if (signr > 0) {
                 if (restart_syscall)
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 8ce247ac04cc..d54c6e53aba0 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -519,10 +519,26 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
         siginfo_t info;
         int signr;
 
+        /* It's a lot of work and synchronization to add a new ptrace
+         * register for GDB to save and restore in order to get
+         * orig_i0 correct for syscall restarts when debugging.
+         *
+         * Although it should be the case that most of the global
+         * registers are volatile across a system call, glibc already
+         * depends upon that fact that we preserve them.  So we can't
+         * just use any global register to save away the orig_i0 value.
+         *
+         * In particular %g2, %g3, %g4, and %g5 are all assumed to be
+         * preserved across a system call trap by various pieces of
+         * code in glibc.
+         *
+         * %g7 is used as the "thread register".   %g6 is not used in
+         * any fixed manner.  %g6 is used as a scratch register and
+         * a compiler temporary, but it's value is never used across
+         * a system call.  Therefore %g6 is usable for orig_i0 storage.
+         */
         if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C))
-                restart_syscall = 1;
-        else
-                restart_syscall = 0;
+                regs->u_regs[UREG_G6] = orig_i0;
 
         if (test_thread_flag(TIF_RESTORE_SIGMASK))
                 oldset = &current->saved_sigmask;
@@ -535,8 +551,12 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
          * the software "in syscall" bit, directing us to not perform
          * a syscall restart.
          */
-        if (restart_syscall && !pt_regs_is_syscall(regs))
-                restart_syscall = 0;
+        restart_syscall = 0;
+        if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) {
+                restart_syscall = 1;
+                orig_i0 = regs->u_regs[UREG_G6];
+        }
+
 
         if (signr > 0) {
                 if (restart_syscall)
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
index a2b81598d905..f0836cd0e2f2 100644
--- a/arch/sparc/kernel/signal_64.c
+++ b/arch/sparc/kernel/signal_64.c
@@ -529,11 +529,27 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
         siginfo_t info;
         int signr;
         
+        /* It's a lot of work and synchronization to add a new ptrace
+         * register for GDB to save and restore in order to get
+         * orig_i0 correct for syscall restarts when debugging.
+         *
+         * Although it should be the case that most of the global
+         * registers are volatile across a system call, glibc already
+         * depends upon that fact that we preserve them.  So we can't
+         * just use any global register to save away the orig_i0 value.
+         *
+         * In particular %g2, %g3, %g4, and %g5 are all assumed to be
+         * preserved across a system call trap by various pieces of
+         * code in glibc.
+         *
+         * %g7 is used as the "thread register".   %g6 is not used in
+         * any fixed manner.  %g6 is used as a scratch register and
+         * a compiler temporary, but it's value is never used across
+         * a system call.  Therefore %g6 is usable for orig_i0 storage.
+         */
         if (pt_regs_is_syscall(regs) &&
-            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
-                restart_syscall = 1;
-        } else
-                restart_syscall = 0;
+            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
+                regs->u_regs[UREG_G6] = orig_i0;
 
         if (current_thread_info()->status & TS_RESTORE_SIGMASK)
                 oldset = &current->saved_sigmask;
@@ -542,22 +558,20 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
 
 #ifdef CONFIG_COMPAT
         if (test_thread_flag(TIF_32BIT)) {
-                extern void do_signal32(sigset_t *, struct pt_regs *,
-                                        int restart_syscall,
-                                        unsigned long orig_i0);
-                do_signal32(oldset, regs, restart_syscall, orig_i0);
+                extern void do_signal32(sigset_t *, struct pt_regs *);
+                do_signal32(oldset, regs);
                 return;
         }
 #endif  
 
         signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 
-        /* If the debugger messes with the program counter, it clears
-         * the software "in syscall" bit, directing us to not perform
-         * a syscall restart.
-         */
-        if (restart_syscall && !pt_regs_is_syscall(regs))
-                restart_syscall = 0;
+        restart_syscall = 0;
+        if (pt_regs_is_syscall(regs) &&
+            (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
+                restart_syscall = 1;
+                orig_i0 = regs->u_regs[UREG_G6];
+        }
 
         if (signr > 0) {
                 if (restart_syscall)
diff --git a/arch/sparc/kernel/sigutil_64.c b/arch/sparc/kernel/sigutil_64.c
index e7dc508c38eb..b19570d41a39 100644
--- a/arch/sparc/kernel/sigutil_64.c
+++ b/arch/sparc/kernel/sigutil_64.c
@@ -2,6 +2,7 @@
 #include <linux/types.h>
 #include <linux/thread_info.h>
 #include <linux/uaccess.h>
+#include <linux/errno.h>
 
 #include <asm/sigcontext.h>
 #include <asm/fpumacro.h>