diff options
Diffstat (limited to 'arch/sparc/mm/fault_64.c')
| -rw-r--r-- | arch/sparc/mm/fault_64.c | 206 |
1 files changed, 139 insertions, 67 deletions
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c index 6081936bf03..587cd056512 100644 --- a/arch/sparc/mm/fault_64.c +++ b/arch/sparc/mm/fault_64.c @@ -16,10 +16,12 @@ #include <linux/mm.h> #include <linux/module.h> #include <linux/init.h> +#include <linux/perf_event.h> #include <linux/interrupt.h> #include <linux/kprobes.h> #include <linux/kdebug.h> #include <linux/percpu.h> +#include <linux/context_tracking.h> #include <asm/page.h> #include <asm/pgtable.h> @@ -30,6 +32,9 @@ #include <asm/lsu.h> #include <asm/sections.h> #include <asm/mmu_context.h> +#include <asm/setup.h> + +int show_unhandled_signals = 1; static inline __kprobes int notify_page_fault(struct pt_regs *regs) { @@ -92,63 +97,106 @@ static unsigned int get_user_insn(unsigned long tpc) pte_t *ptep, pte; unsigned long pa; u32 insn = 0; - unsigned long pstate; - if (pgd_none(*pgdp)) - goto outret; + if (pgd_none(*pgdp) || unlikely(pgd_bad(*pgdp))) + goto out; pudp = pud_offset(pgdp, tpc); - if (pud_none(*pudp)) - goto outret; - pmdp = pmd_offset(pudp, tpc); - if (pmd_none(*pmdp)) - goto outret; - - /* This disables preemption for us as well. */ - __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate)); - __asm__ __volatile__("wrpr %0, %1, %%pstate" - : : "r" (pstate), "i" (PSTATE_IE)); - ptep = pte_offset_map(pmdp, tpc); - pte = *ptep; - if (!pte_present(pte)) + if (pud_none(*pudp) || unlikely(pud_bad(*pudp))) goto out; - pa = (pte_pfn(pte) << PAGE_SHIFT); - pa += (tpc & ~PAGE_MASK); - - /* Use phys bypass so we don't pollute dtlb/dcache. */ - __asm__ __volatile__("lduwa [%1] %2, %0" - : "=r" (insn) - : "r" (pa), "i" (ASI_PHYS_USE_EC)); + /* This disables preemption for us as well. */ + local_irq_disable(); + pmdp = pmd_offset(pudp, tpc); + if (pmd_none(*pmdp) || unlikely(pmd_bad(*pmdp))) + goto out_irq_enable; + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (pmd_trans_huge(*pmdp)) { + if (pmd_trans_splitting(*pmdp)) + goto out_irq_enable; + + pa = pmd_pfn(*pmdp) << PAGE_SHIFT; + pa += tpc & ~HPAGE_MASK; + + /* Use phys bypass so we don't pollute dtlb/dcache. */ + __asm__ __volatile__("lduwa [%1] %2, %0" + : "=r" (insn) + : "r" (pa), "i" (ASI_PHYS_USE_EC)); + } else +#endif + { + ptep = pte_offset_map(pmdp, tpc); + pte = *ptep; + if (pte_present(pte)) { + pa = (pte_pfn(pte) << PAGE_SHIFT); + pa += (tpc & ~PAGE_MASK); + + /* Use phys bypass so we don't pollute dtlb/dcache. */ + __asm__ __volatile__("lduwa [%1] %2, %0" + : "=r" (insn) + : "r" (pa), "i" (ASI_PHYS_USE_EC)); + } + pte_unmap(ptep); + } +out_irq_enable: + local_irq_enable(); out: - pte_unmap(ptep); - __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate)); -outret: return insn; } -extern unsigned long compute_effective_address(struct pt_regs *, unsigned int, unsigned int); +static inline void +show_signal_msg(struct pt_regs *regs, int sig, int code, + unsigned long address, struct task_struct *tsk) +{ + if (!unhandled_signal(tsk, sig)) + return; + + if (!printk_ratelimit()) + return; + + printk("%s%s[%d]: segfault at %lx ip %p (rpc %p) sp %p error %x", + task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG, + tsk->comm, task_pid_nr(tsk), address, + (void *)regs->tpc, (void *)regs->u_regs[UREG_I7], + (void *)regs->u_regs[UREG_FP], code); + + print_vma_addr(KERN_CONT " in ", regs->tpc); + + printk(KERN_CONT "\n"); +} static void do_fault_siginfo(int code, int sig, struct pt_regs *regs, - unsigned int insn, int fault_code) + unsigned long fault_addr, unsigned int insn, + int fault_code) { + unsigned long addr; siginfo_t info; info.si_code = code; info.si_signo = sig; info.si_errno = 0; - if (fault_code & FAULT_CODE_ITLB) - info.si_addr = (void __user *) regs->tpc; - else - info.si_addr = (void __user *) - compute_effective_address(regs, insn, 0); + if (fault_code & FAULT_CODE_ITLB) { + addr = regs->tpc; + } else { + /* If we were able to probe the faulting instruction, use it + * to compute a precise fault address. Otherwise use the fault + * time provided address which may only have page granularity. + */ + if (insn) + addr = compute_effective_address(regs, insn, 0); + else + addr = fault_addr; + } + info.si_addr = (void __user *) addr; info.si_trapno = 0; + + if (unlikely(show_unhandled_signals)) + show_signal_msg(regs, sig, code, addr, current); + force_sig_info(sig, &info, current); } -extern int handle_ldf_stq(u32, struct pt_regs *); -extern int handle_ld_nf(u32, struct pt_regs *); - static unsigned int get_fault_insn(struct pt_regs *regs, unsigned int insn) { if (!insn) { @@ -211,7 +259,7 @@ static void __kprobes do_kernel_fault(struct pt_regs *regs, int si_code, /* The si_code was set to make clear whether * this was a SEGV_MAPERR or SEGV_ACCERR fault. */ - do_fault_siginfo(si_code, SIGSEGV, regs, insn, fault_code); + do_fault_siginfo(si_code, SIGSEGV, regs, address, insn, fault_code); return; } @@ -231,30 +279,20 @@ static void noinline __kprobes bogus_32bit_fault_tpc(struct pt_regs *regs) show_regs(regs); } -static void noinline __kprobes bogus_32bit_fault_address(struct pt_regs *regs, - unsigned long addr) -{ - static int times; - - if (times++ < 10) - printk(KERN_ERR "FAULT[%s:%d]: 32-bit process " - "reports 64-bit fault address [%lx]\n", - current->comm, current->pid, addr); - show_regs(regs); -} - asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) { + enum ctx_state prev_state = exception_enter(); struct mm_struct *mm = current->mm; struct vm_area_struct *vma; unsigned int insn = 0; int si_code, fault_code, fault; unsigned long address, mm_rss; + unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; fault_code = get_thread_fault_code(); if (notify_page_fault(regs)) - return; + goto exit_exception; si_code = SEGV_MAPERR; address = current_thread_info()->fault_address; @@ -270,10 +308,8 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) goto intr_or_no_mm; } } - if (unlikely((address >> 32) != 0)) { - bogus_32bit_fault_address(regs, address); + if (unlikely((address >> 32) != 0)) goto intr_or_no_mm; - } } if (regs->tstate & TSTATE_PRIV) { @@ -285,9 +321,10 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) /* Valid, no problems... */ } else { bad_kernel_pc(regs, address); - return; + goto exit_exception; } - } + } else + flags |= FAULT_FLAG_USER; /* * If we're in an interrupt or have no user @@ -296,12 +333,16 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) if (in_atomic() || !mm) goto intr_or_no_mm; + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); + if (!down_read_trylock(&mm->mmap_sem)) { if ((regs->tstate & TSTATE_PRIV) && !search_exception_tables(regs->tpc)) { insn = get_fault_insn(regs, insn); goto handle_kernel_fault; } + +retry: down_read(&mm->mmap_sem); } @@ -386,13 +427,19 @@ good_area: vma->vm_file != NULL) set_thread_fault_code(fault_code | FAULT_CODE_BLKCOMMIT); + + flags |= FAULT_FLAG_WRITE; } else { /* Allow reads even for write-only mappings */ if (!(vma->vm_flags & (VM_READ | VM_EXEC))) goto bad_area; } - fault = handle_mm_fault(mm, vma, address, (fault_code & FAULT_CODE_WRITE) ? FAULT_FLAG_WRITE : 0); + fault = handle_mm_fault(mm, vma, address, flags); + + if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) + goto exit_exception; + if (unlikely(fault & VM_FAULT_ERROR)) { if (fault & VM_FAULT_OOM) goto out_of_memory; @@ -400,26 +447,51 @@ good_area: goto do_sigbus; BUG(); } - if (fault & VM_FAULT_MAJOR) - current->maj_flt++; - else - current->min_flt++; + if (flags & FAULT_FLAG_ALLOW_RETRY) { + if (fault & VM_FAULT_MAJOR) { + current->maj_flt++; + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, + 1, regs, address); + } else { + current->min_flt++; + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, + 1, regs, address); + } + if (fault & VM_FAULT_RETRY) { + flags &= ~FAULT_FLAG_ALLOW_RETRY; + flags |= FAULT_FLAG_TRIED; + + /* No need to up_read(&mm->mmap_sem) as we would + * have already released it in __lock_page_or_retry + * in mm/filemap.c. + */ + + goto retry; + } + } up_read(&mm->mmap_sem); mm_rss = get_mm_rss(mm); -#ifdef CONFIG_HUGETLB_PAGE +#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) mm_rss -= (mm->context.huge_pte_count * (HPAGE_SIZE / PAGE_SIZE)); #endif if (unlikely(mm_rss > mm->context.tsb_block[MM_TSB_BASE].tsb_rss_limit)) tsb_grow(mm, MM_TSB_BASE, mm_rss); -#ifdef CONFIG_HUGETLB_PAGE +#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) mm_rss = mm->context.huge_pte_count; if (unlikely(mm_rss > - mm->context.tsb_block[MM_TSB_HUGE].tsb_rss_limit)) - tsb_grow(mm, MM_TSB_HUGE, mm_rss); + mm->context.tsb_block[MM_TSB_HUGE].tsb_rss_limit)) { + if (mm->context.tsb_block[MM_TSB_HUGE].tsb) + tsb_grow(mm, MM_TSB_HUGE, mm_rss); + else + hugetlb_setup(regs); + + } #endif +exit_exception: + exception_exit(prev_state); return; /* @@ -432,7 +504,7 @@ bad_area: handle_kernel_fault: do_kernel_fault(regs, si_code, fault_code, insn, address); - return; + goto exit_exception; /* * We ran out of memory, or some other thing happened to us that made @@ -443,7 +515,7 @@ out_of_memory: up_read(&mm->mmap_sem); if (!(regs->tstate & TSTATE_PRIV)) { pagefault_out_of_memory(); - return; + goto exit_exception; } goto handle_kernel_fault; @@ -459,7 +531,7 @@ do_sigbus: * Send a sigbus, regardless of whether we were in kernel * or user mode. */ - do_fault_siginfo(BUS_ADRERR, SIGBUS, regs, insn, fault_code); + do_fault_siginfo(BUS_ADRERR, SIGBUS, regs, address, insn, fault_code); /* Kernel mode? Handle exceptions or die */ if (regs->tstate & TSTATE_PRIV) |
