Index: stable/12/sys/arm/arm/trap-v6.c =================================================================== --- stable/12/sys/arm/arm/trap-v6.c (revision 367226) +++ stable/12/sys/arm/arm/trap-v6.c (revision 367227) @@ -1,665 +1,671 @@ /*- * Copyright 2014 Olivier Houchard * Copyright 2014 Svatopluk Kraus * Copyright 2014 Michal Meloun * Copyright 2014 Andrew Turner * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "opt_ktrace.h" #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #include #endif #include #include #include #include #include #include #include #include #include #include #ifdef KDB #include #include #endif #ifdef KDTRACE_HOOKS #include #endif extern char cachebailout[]; #ifdef DEBUG int last_fault_code; /* For the benefit of pmap_fault_fixup() */ #endif struct ksig { int sig; u_long code; vm_offset_t addr; }; typedef int abort_func_t(struct trapframe *, u_int, u_int, u_int, u_int, struct thread *, struct ksig *); static abort_func_t abort_fatal; static abort_func_t abort_align; static abort_func_t abort_icache; struct abort { abort_func_t *func; const char *desc; }; /* * How are the aborts handled? * * Undefined Code: * - Always fatal as we do not know what does it mean. * Imprecise External Abort: * - Always fatal, but can be handled somehow in the future. * Now, due to PCIe buggy hardware, ignored. * Precise External Abort: * - Always fatal, but who knows in the future??? * Debug Event: * - Special handling. * External Translation Abort (L1 & L2) * - Always fatal as something is screwed up in page tables or hardware. * Domain Fault (L1 & L2): * - Always fatal as we do not play game with domains. * Alignment Fault: * - Everything should be aligned in kernel with exception of user to kernel * and vice versa data copying, so if pcb_onfault is not set, it's fatal. * We generate signal in case of abort from user mode. * Instruction cache maintenance: * - According to manual, this is translation fault during cache maintenance * operation. So, it could be really complex in SMP case and fuzzy too * for cache operations working on virtual addresses. For now, we will * consider this abort as fatal. In fact, no cache maintenance on * not mapped virtual addresses should be called. As cache maintenance * operation (except DMB, DSB, and Flush Prefetch Buffer) are priviledged, * the abort is fatal for user mode as well for now. (This is good place to * note that cache maintenance on virtual address fill TLB.) * Acces Bit (L1 & L2): * - Fast hardware emulation for kernel and user mode. * Translation Fault (L1 & L2): * - Standard fault mechanism is held including vm_fault(). * Permission Fault (L1 & L2): * - Fast hardware emulation of modify bits and in other cases, standard * fault mechanism is held including vm_fault(). */ static const struct abort aborts[] = { {abort_fatal, "Undefined Code (0x000)"}, {abort_align, "Alignment Fault"}, {abort_fatal, "Debug Event"}, {NULL, "Access Bit (L1)"}, {NULL, "Instruction cache maintenance"}, {NULL, "Translation Fault (L1)"}, {NULL, "Access Bit (L2)"}, {NULL, "Translation Fault (L2)"}, {abort_fatal, "External Abort"}, {abort_fatal, "Domain Fault (L1)"}, {abort_fatal, "Undefined Code (0x00A)"}, {abort_fatal, "Domain Fault (L2)"}, {abort_fatal, "External Translation Abort (L1)"}, {NULL, "Permission Fault (L1)"}, {abort_fatal, "External Translation Abort (L2)"}, {NULL, "Permission Fault (L2)"}, {abort_fatal, "TLB Conflict Abort"}, {abort_fatal, "Undefined Code (0x401)"}, {abort_fatal, "Undefined Code (0x402)"}, {abort_fatal, "Undefined Code (0x403)"}, {abort_fatal, "Undefined Code (0x404)"}, {abort_fatal, "Undefined Code (0x405)"}, {abort_fatal, "Asynchronous External Abort"}, {abort_fatal, "Undefined Code (0x407)"}, {abort_fatal, "Asynchronous Parity Error on Memory Access"}, {abort_fatal, "Parity Error on Memory Access"}, {abort_fatal, "Undefined Code (0x40A)"}, {abort_fatal, "Undefined Code (0x40B)"}, {abort_fatal, "Parity Error on Translation (L1)"}, {abort_fatal, "Undefined Code (0x40D)"}, {abort_fatal, "Parity Error on Translation (L2)"}, {abort_fatal, "Undefined Code (0x40F)"} }; static __inline void call_trapsignal(struct thread *td, int sig, int code, vm_offset_t addr) { ksiginfo_t ksi; CTR4(KTR_TRAP, "%s: addr: %#x, sig: %d, code: %d", __func__, addr, sig, code); /* * TODO: some info would be nice to know * if we are serving data or prefetch abort. */ ksiginfo_init_trap(&ksi); ksi.ksi_signo = sig; ksi.ksi_code = code; ksi.ksi_addr = (void *)addr; trapsignal(td, &ksi); } /* * abort_imprecise() handles the following abort: * * FAULT_EA_IMPREC - Imprecise External Abort * * The imprecise means that we don't know where the abort happened, * thus FAR is undefined. The abort should not never fire, but hot * plugging or accidental hardware failure can be the cause of it. * If the abort happens, it can even be on different (thread) context. * Without any additional support, the abort is fatal, as we do not * know what really happened. * * QQQ: Some additional functionality, like pcb_onfault but global, * can be implemented. Imprecise handlers could be registered * which tell us if the abort is caused by something they know * about. They should return one of three codes like: * FAULT_IS_MINE, * FAULT_CAN_BE_MINE, * FAULT_IS_NOT_MINE. * The handlers should be called until some of them returns * FAULT_IS_MINE value or all was called. If all handlers return * FAULT_IS_NOT_MINE value, then the abort is fatal. */ static __inline void abort_imprecise(struct trapframe *tf, u_int fsr, u_int prefetch, bool usermode) { /* * XXX - We can got imprecise abort as result of access * to not-present PCI/PCIe configuration space. */ #if 0 goto out; #endif abort_fatal(tf, FAULT_EA_IMPREC, fsr, 0, prefetch, curthread, NULL); /* * Returning from this function means that we ignore * the abort for good reason. Note that imprecise abort * could fire any time even in user mode. */ #if 0 out: if (usermode) userret(curthread, tf); #endif } /* * abort_debug() handles the following abort: * * FAULT_DEBUG - Debug Event * */ static __inline void abort_debug(struct trapframe *tf, u_int fsr, u_int prefetch, bool usermode, u_int far) { if (usermode) { struct thread *td; td = curthread; call_trapsignal(td, SIGTRAP, TRAP_BRKPT, far); userret(td, tf); } else { #ifdef KDB kdb_trap((prefetch) ? T_BREAKPOINT : T_WATCHPOINT, 0, tf); #else printf("No debugger in kernel.\n"); #endif } } /* * Abort handler. * * FAR, FSR, and everything what can be lost after enabling * interrupts must be grabbed before the interrupts will be * enabled. Note that when interrupts will be enabled, we * could even migrate to another CPU ... * * TODO: move quick cases to ASM */ void abort_handler(struct trapframe *tf, int prefetch) { struct thread *td; vm_offset_t far, va; int idx, rv; uint32_t fsr; struct ksig ksig; struct proc *p; struct pcb *pcb; struct vm_map *map; struct vmspace *vm; vm_prot_t ftype; bool usermode; int bp_harden, ucode; #ifdef INVARIANTS void *onfault; #endif VM_CNT_INC(v_trap); td = curthread; fsr = (prefetch) ? cp15_ifsr_get(): cp15_dfsr_get(); #if __ARM_ARCH >= 7 far = (prefetch) ? cp15_ifar_get() : cp15_dfar_get(); #else far = (prefetch) ? TRAPF_PC(tf) : cp15_dfar_get(); #endif idx = FSR_TO_FAULT(fsr); usermode = TRAPF_USERMODE(tf); /* Abort came from user mode? */ /* * Apply BP hardening by flushing the branch prediction cache * for prefaults on kernel addresses. */ if (__predict_false(prefetch && far > VM_MAXUSER_ADDRESS && (idx == FAULT_TRAN_L2 || idx == FAULT_PERM_L2))) { bp_harden = PCPU_GET(bp_harden_kind); if (bp_harden == PCPU_BP_HARDEN_KIND_BPIALL) _CP15_BPIALL(); else if (bp_harden == PCPU_BP_HARDEN_KIND_ICIALLU) _CP15_ICIALLU(); } if (usermode) td->td_frame = tf; CTR6(KTR_TRAP, "%s: fsr %#x (idx %u) far %#x prefetch %u usermode %d", __func__, fsr, idx, far, prefetch, usermode); /* * Firstly, handle aborts that are not directly related to mapping. */ if (__predict_false(idx == FAULT_EA_IMPREC)) { abort_imprecise(tf, fsr, prefetch, usermode); return; } if (__predict_false(idx == FAULT_DEBUG)) { abort_debug(tf, fsr, prefetch, usermode, far); return; } /* * ARM has a set of unprivileged load and store instructions * (LDRT/LDRBT/STRT/STRBT ...) which are supposed to be used in other * than user mode and OS should recognize their aborts and behave * appropriately. However, there is no way how to do that reasonably * in general unless we restrict the handling somehow. * * For now, these instructions are used only in copyin()/copyout() * like functions where usermode buffers are checked in advance that * they are not from KVA space. Thus, no action is needed here. */ /* * (1) Handle access and R/W hardware emulation aborts. * (2) Check that abort is not on pmap essential address ranges. * There is no way how to fix it, so we don't even try. */ rv = pmap_fault(PCPU_GET(curpmap), far, fsr, idx, usermode); if (rv == KERN_SUCCESS) return; #ifdef KDB if (kdb_active) { kdb_reenter(); goto out; } #endif if (rv == KERN_INVALID_ADDRESS) goto nogo; if (__predict_false((td->td_pflags & TDP_NOFAULTING) != 0)) { /* * Due to both processor errata and lazy TLB invalidation when * access restrictions are removed from virtual pages, memory * accesses that are allowed by the physical mapping layer may * nonetheless cause one spurious page fault per virtual page. * When the thread is executing a "no faulting" section that * is bracketed by vm_fault_{disable,enable}_pagefaults(), * every page fault is treated as a spurious page fault, * unless it accesses the same virtual address as the most * recent page fault within the same "no faulting" section. */ if (td->td_md.md_spurflt_addr != far || (td->td_pflags & TDP_RESETSPUR) != 0) { td->td_md.md_spurflt_addr = far; td->td_pflags &= ~TDP_RESETSPUR; tlb_flush_local(far & ~PAGE_MASK); return; } } else { /* * If we get a page fault while in a critical section, then * it is most likely a fatal kernel page fault. The kernel * is already going to panic trying to get a sleep lock to * do the VM lookup, so just consider it a fatal trap so the * kernel can print out a useful trap message and even get * to the debugger. * * If we get a page fault while holding a non-sleepable * lock, then it is most likely a fatal kernel page fault. * If WITNESS is enabled, then it's going to whine about * bogus LORs with various VM locks, so just skip to the * fatal trap handling directly. */ if (td->td_critnest != 0 || WITNESS_CHECK(WARN_SLEEPOK | WARN_GIANTOK, NULL, "Kernel page fault") != 0) { abort_fatal(tf, idx, fsr, far, prefetch, td, &ksig); return; } } /* Re-enable interrupts if they were enabled previously. */ if (td->td_md.md_spinlock_count == 0) { if (__predict_true(tf->tf_spsr & PSR_I) == 0) enable_interrupts(PSR_I); if (__predict_true(tf->tf_spsr & PSR_F) == 0) enable_interrupts(PSR_F); } p = td->td_proc; if (usermode) { td->td_pticks = 0; if (td->td_cowgen != p->p_cowgen) thread_cow_update(td); } /* Invoke the appropriate handler, if necessary. */ if (__predict_false(aborts[idx].func != NULL)) { if ((aborts[idx].func)(tf, idx, fsr, far, prefetch, td, &ksig)) goto do_trapsignal; goto out; } /* * At this point, we're dealing with one of the following aborts: * * FAULT_ICACHE - I-cache maintenance * FAULT_TRAN_xx - Translation * FAULT_PERM_xx - Permission */ /* * Don't pass faulting cache operation to vm_fault(). We don't want * to handle all vm stuff at this moment. */ pcb = td->td_pcb; if (__predict_false(pcb->pcb_onfault == cachebailout)) { tf->tf_r0 = far; /* return failing address */ tf->tf_pc = (register_t)pcb->pcb_onfault; return; } /* Handle remaining I-cache aborts. */ if (idx == FAULT_ICACHE) { if (abort_icache(tf, idx, fsr, far, prefetch, td, &ksig)) goto do_trapsignal; goto out; } va = trunc_page(far); if (va >= KERNBASE) { /* * Don't allow user-mode faults in kernel address space. */ - if (usermode) + if (usermode) { + ksig.sig = SIGSEGV; + ksig.code = SEGV_ACCERR; goto nogo; + } map = kernel_map; } else { /* * This is a fault on non-kernel virtual memory. If curproc * is NULL or curproc->p_vmspace is NULL the fault is fatal. */ vm = (p != NULL) ? p->p_vmspace : NULL; - if (vm == NULL) + if (vm == NULL) { + ksig.sig = SIGSEGV; + ksig.code = 0; goto nogo; + } map = &vm->vm_map; if (!usermode && (td->td_intr_nesting_level != 0 || pcb->pcb_onfault == NULL)) { abort_fatal(tf, idx, fsr, far, prefetch, td, &ksig); return; } } ftype = (fsr & FSR_WNR) ? VM_PROT_WRITE : VM_PROT_READ; if (prefetch) ftype |= VM_PROT_EXECUTE; #ifdef DEBUG last_fault_code = fsr; #endif #ifdef INVARIANTS onfault = pcb->pcb_onfault; pcb->pcb_onfault = NULL; #endif /* Fault in the page. */ rv = vm_fault_trap(map, va, ftype, VM_FAULT_NORMAL, &ksig.sig, &ucode); ksig.code = ucode; #ifdef INVARIANTS pcb->pcb_onfault = onfault; #endif if (__predict_true(rv == KERN_SUCCESS)) goto out; nogo: if (!usermode) { if (td->td_intr_nesting_level == 0 && pcb->pcb_onfault != NULL) { tf->tf_r0 = rv; tf->tf_pc = (int)pcb->pcb_onfault; return; } CTR2(KTR_TRAP, "%s: vm_fault() failed with %d", __func__, rv); abort_fatal(tf, idx, fsr, far, prefetch, td, &ksig); return; } ksig.addr = far; do_trapsignal: call_trapsignal(td, ksig.sig, ksig.code, ksig.addr); out: if (usermode) userret(td, tf); } /* * abort_fatal() handles the following data aborts: * * FAULT_DEBUG - Debug Event * FAULT_ACCESS_xx - Acces Bit * FAULT_EA_PREC - Precise External Abort * FAULT_DOMAIN_xx - Domain Fault * FAULT_EA_TRAN_xx - External Translation Abort * FAULT_EA_IMPREC - Imprecise External Abort * + all undefined codes for ABORT * * We should never see these on a properly functioning system. * * This function is also called by the other handlers if they * detect a fatal problem. * * Note: If 'l' is NULL, we assume we're dealing with a prefetch abort. */ static int abort_fatal(struct trapframe *tf, u_int idx, u_int fsr, u_int far, u_int prefetch, struct thread *td, struct ksig *ksig) { bool usermode; const char *mode; const char *rw_mode; usermode = TRAPF_USERMODE(tf); #ifdef KDTRACE_HOOKS if (!usermode) { if (dtrace_trap_func != NULL && (*dtrace_trap_func)(tf, far)) return (0); } #endif mode = usermode ? "user" : "kernel"; rw_mode = fsr & FSR_WNR ? "write" : "read"; disable_interrupts(PSR_I|PSR_F); if (td != NULL) { printf("Fatal %s mode data abort: '%s' on %s\n", mode, aborts[idx].desc, rw_mode); printf("trapframe: %p\nFSR=%08x, FAR=", tf, fsr); if (idx != FAULT_EA_IMPREC) printf("%08x, ", far); else printf("Invalid, "); printf("spsr=%08x\n", tf->tf_spsr); } else { printf("Fatal %s mode prefetch abort at 0x%08x\n", mode, tf->tf_pc); printf("trapframe: %p, spsr=%08x\n", tf, tf->tf_spsr); } printf("r0 =%08x, r1 =%08x, r2 =%08x, r3 =%08x\n", tf->tf_r0, tf->tf_r1, tf->tf_r2, tf->tf_r3); printf("r4 =%08x, r5 =%08x, r6 =%08x, r7 =%08x\n", tf->tf_r4, tf->tf_r5, tf->tf_r6, tf->tf_r7); printf("r8 =%08x, r9 =%08x, r10=%08x, r11=%08x\n", tf->tf_r8, tf->tf_r9, tf->tf_r10, tf->tf_r11); printf("r12=%08x, ", tf->tf_r12); if (usermode) printf("usp=%08x, ulr=%08x", tf->tf_usr_sp, tf->tf_usr_lr); else printf("ssp=%08x, slr=%08x", tf->tf_svc_sp, tf->tf_svc_lr); printf(", pc =%08x\n\n", tf->tf_pc); #ifdef KDB if (debugger_on_trap) { kdb_why = KDB_WHY_TRAP; kdb_trap(fsr, 0, tf); kdb_why = KDB_WHY_UNSET; } #endif panic("Fatal abort"); /*NOTREACHED*/ } /* * abort_align() handles the following data abort: * * FAULT_ALIGN - Alignment fault * * Everything should be aligned in kernel with exception of user to kernel * and vice versa data copying, so if pcb_onfault is not set, it's fatal. * We generate signal in case of abort from user mode. */ static int abort_align(struct trapframe *tf, u_int idx, u_int fsr, u_int far, u_int prefetch, struct thread *td, struct ksig *ksig) { bool usermode; usermode = TRAPF_USERMODE(tf); if (!usermode) { if (td->td_intr_nesting_level == 0 && td != NULL && td->td_pcb->pcb_onfault != NULL) { tf->tf_r0 = EFAULT; tf->tf_pc = (int)td->td_pcb->pcb_onfault; return (0); } abort_fatal(tf, idx, fsr, far, prefetch, td, ksig); } /* Deliver a bus error signal to the process */ ksig->code = BUS_ADRALN; ksig->sig = SIGBUS; ksig->addr = far; return (1); } /* * abort_icache() handles the following data abort: * * FAULT_ICACHE - Instruction cache maintenance * * According to manual, FAULT_ICACHE is translation fault during cache * maintenance operation. In fact, no cache maintenance operation on * not mapped virtual addresses should be called. As cache maintenance * operation (except DMB, DSB, and Flush Prefetch Buffer) are priviledged, * the abort is concider as fatal for now. However, all the matter with * cache maintenance operation on virtual addresses could be really complex * and fuzzy in SMP case, so maybe in future standard fault mechanism * should be held here including vm_fault() calling. */ static int abort_icache(struct trapframe *tf, u_int idx, u_int fsr, u_int far, u_int prefetch, struct thread *td, struct ksig *ksig) { abort_fatal(tf, idx, fsr, far, prefetch, td, ksig); return(0); } Index: stable/12 =================================================================== --- stable/12 (revision 367226) +++ stable/12 (revision 367227) Property changes on: stable/12 ___________________________________________________________________ Modified: svn:mergeinfo ## -0,0 +0,1 ## Merged /head:r366197