]> bbs.cooldavid.org Git - net-next-2.6.git/blobdiff - arch/sparc/kernel/signal32.c
sparc: Don't mask signal when we can't setup signal frame.
[net-next-2.6.git] / arch / sparc / kernel / signal32.c
index ea22cd373c64f4bc371478d2b7be14f71cd32560..643a354795cc70aa422354ece784ef44797e23a6 100644 (file)
@@ -453,8 +453,66 @@ static int save_fpu_state32(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
        return err;
 }
 
-static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
-                         int signo, sigset_t *oldset)
+/* The I-cache flush instruction only works in the primary ASI, which
+ * right now is the nucleus, aka. kernel space.
+ *
+ * Therefore we have to kick the instructions out using the kernel
+ * side linear mapping of the physical address backing the user
+ * instructions.
+ */
+static void flush_signal_insns(unsigned long address)
+{
+       unsigned long pstate, paddr;
+       pte_t *ptep, pte;
+       pgd_t *pgdp;
+       pud_t *pudp;
+       pmd_t *pmdp;
+
+       /* Commit all stores of the instructions we are about to flush.  */
+       wmb();
+
+       /* Disable cross-call reception.  In this way even a very wide
+        * munmap() on another cpu can't tear down the page table
+        * hierarchy from underneath us, since that can't complete
+        * until the IPI tlb flush returns.
+        */
+
+       __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
+       __asm__ __volatile__("wrpr %0, %1, %%pstate"
+                               : : "r" (pstate), "i" (PSTATE_IE));
+
+       pgdp = pgd_offset(current->mm, address);
+       if (pgd_none(*pgdp))
+               goto out_irqs_on;
+       pudp = pud_offset(pgdp, address);
+       if (pud_none(*pudp))
+               goto out_irqs_on;
+       pmdp = pmd_offset(pudp, address);
+       if (pmd_none(*pmdp))
+               goto out_irqs_on;
+
+       ptep = pte_offset_map(pmdp, address);
+       pte = *ptep;
+       if (!pte_present(pte))
+               goto out_unmap;
+
+       paddr = (unsigned long) page_address(pte_page(pte));
+
+       __asm__ __volatile__("flush     %0 + %1"
+                            : /* no outputs */
+                            : "r" (paddr),
+                              "r" (address & (PAGE_SIZE - 1))
+                            : "memory");
+
+out_unmap:
+       pte_unmap(ptep);
+out_irqs_on:
+       __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
+
+}
+
+static int setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
+                        int signo, sigset_t *oldset)
 {
        struct signal_frame32 __user *sf;
        int sigframe_size;
@@ -547,13 +605,7 @@ static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
        if (ka->ka_restorer) {
                regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
        } else {
-               /* Flush instruction space. */
                unsigned long address = ((unsigned long)&(sf->insns[0]));
-               pgd_t *pgdp = pgd_offset(current->mm, address);
-               pud_t *pudp = pud_offset(pgdp, address);
-               pmd_t *pmdp = pmd_offset(pudp, address);
-               pte_t *ptep;
-               pte_t pte;
 
                regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
        
@@ -562,34 +614,22 @@ static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
                if (err)
                        goto sigsegv;
 
-               preempt_disable();
-               ptep = pte_offset_map(pmdp, address);
-               pte = *ptep;
-               if (pte_present(pte)) {
-                       unsigned long page = (unsigned long)
-                               page_address(pte_page(pte));
-
-                       wmb();
-                       __asm__ __volatile__("flush     %0 + %1"
-                                            : /* no outputs */
-                                            : "r" (page),
-                                              "r" (address & (PAGE_SIZE - 1))
-                                            : "memory");
-               }
-               pte_unmap(ptep);
-               preempt_enable();
+               flush_signal_insns(address);
        }
        return;
 
 sigill:
        do_exit(SIGILL);
+       return -EINVAL;
+
 sigsegv:
        force_sigsegv(signo, current);
+       return -EFAULT;
 }
 
-static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
-                            unsigned long signr, sigset_t *oldset,
-                            siginfo_t *info)
+static int setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
+                           unsigned long signr, sigset_t *oldset,
+                           siginfo_t *info)
 {
        struct rt_signal_frame32 __user *sf;
        int sigframe_size;
@@ -687,12 +727,7 @@ static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
        if (ka->ka_restorer)
                regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
        else {
-               /* Flush instruction space. */
                unsigned long address = ((unsigned long)&(sf->insns[0]));
-               pgd_t *pgdp = pgd_offset(current->mm, address);
-               pud_t *pudp = pud_offset(pgdp, address);
-               pmd_t *pmdp = pmd_offset(pudp, address);
-               pte_t *ptep;
 
                regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
        
@@ -704,38 +739,32 @@ static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
                if (err)
                        goto sigsegv;
 
-               preempt_disable();
-               ptep = pte_offset_map(pmdp, address);
-               if (pte_present(*ptep)) {
-                       unsigned long page = (unsigned long)
-                               page_address(pte_page(*ptep));
-
-                       wmb();
-                       __asm__ __volatile__("flush     %0 + %1"
-                                            : /* no outputs */
-                                            : "r" (page),
-                                              "r" (address & (PAGE_SIZE - 1))
-                                            : "memory");
-               }
-               pte_unmap(ptep);
-               preempt_enable();
+               flush_signal_insns(address);
        }
-       return;
+       return 0;
 
 sigill:
        do_exit(SIGILL);
+       return -EINVAL;
+
 sigsegv:
        force_sigsegv(signr, current);
+       return -EFAULT;
 }
 
-static inline void handle_signal32(unsigned long signr, struct k_sigaction *ka,
-                                  siginfo_t *info,
-                                  sigset_t *oldset, struct pt_regs *regs)
+static inline int handle_signal32(unsigned long signr, struct k_sigaction *ka,
+                                 siginfo_t *info,
+                                 sigset_t *oldset, struct pt_regs *regs)
 {
+       int err;
+
        if (ka->sa.sa_flags & SA_SIGINFO)
-               setup_rt_frame32(ka, regs, signr, oldset, info);
+               err = setup_rt_frame32(ka, regs, signr, oldset, info);
        else
-               setup_frame32(ka, regs, signr, oldset);
+               err = setup_frame32(ka, regs, signr, oldset);
+
+       if (err)
+               return err;
 
        spin_lock_irq(&current->sighand->siglock);
        sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
@@ -743,6 +772,10 @@ static inline void handle_signal32(unsigned long signr, struct k_sigaction *ka,
                sigaddset(&current->blocked,signr);
        recalc_sigpending();
        spin_unlock_irq(&current->sighand->siglock);
+
+       tracehook_signal_handler(signr, info, ka, regs, 0);
+
+       return 0;
 }
 
 static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
@@ -789,16 +822,14 @@ void do_signal32(sigset_t *oldset, struct pt_regs * regs,
        if (signr > 0) {
                if (restart_syscall)
                        syscall_restart32(orig_i0, regs, &ka.sa);
-               handle_signal32(signr, &ka, &info, oldset, regs);
-
-               /* A signal was successfully delivered; the saved
-                * sigmask will have been stored in the signal frame,
-                * and will be restored by sigreturn, so we can simply
-                * clear the TS_RESTORE_SIGMASK flag.
-                */
-               current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
-
-               tracehook_signal_handler(signr, &info, &ka, regs, 0);
+               if (handle_signal32(signr, &ka, &info, oldset, regs) == 0) {
+                       /* A signal was successfully delivered; the saved
+                        * sigmask will have been stored in the signal frame,
+                        * and will be restored by sigreturn, so we can simply
+                        * clear the TS_RESTORE_SIGMASK flag.
+                        */
+                       current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
+               }
                return;
        }
        if (restart_syscall &&