diff options
author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-03-08 10:11:33 -0300 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-03-08 10:11:33 -0300 |
commit | 009ef05f98129aa91c62c3baab859ba593a15bb2 (patch) | |
tree | f3414f08d636a597545b1e4f443b373b9d6d8f4b /arch/riscv/mm/fault.c | |
parent | 2777b81b379df772defd654bc4d3fa82dca17a4b (diff) | |
parent | 144c79ef33536b4ecb4951e07dbc1f2b7fa99d32 (diff) |
Merge remote-tracking branch 'torvalds/master' into perf/core
To pick up the fixes sent for v5.12 and continue development based on
v5.12-rc2, i.e. without the swap on file bug.
This also gets a slightly newer and better tools/perf/arch/arm/util/cs-etm.c
patch version, using the BIT() macro, that had already been slated to
v5.13 but ended up going to v5.12-rc1 on an older version.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'arch/riscv/mm/fault.c')
-rw-r--r-- | arch/riscv/mm/fault.c | 38 |
1 files changed, 32 insertions, 6 deletions
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c index 3c8b9e433c67..8f17519208c7 100644 --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -13,14 +13,30 @@ #include <linux/perf_event.h> #include <linux/signal.h> #include <linux/uaccess.h> +#include <linux/kprobes.h> #include <asm/ptrace.h> #include <asm/tlbflush.h> #include "../kernel/head.h" +static void die_kernel_fault(const char *msg, unsigned long addr, + struct pt_regs *regs) +{ + bust_spinlocks(1); + + pr_alert("Unable to handle kernel %s at virtual address " REG_FMT "\n", msg, + addr); + + bust_spinlocks(0); + die(regs, "Oops"); + do_exit(SIGKILL); +} + static inline void no_context(struct pt_regs *regs, unsigned long addr) { + const char *msg; + /* Are we prepared to handle this kernel fault? */ if (fixup_exception(regs)) return; @@ -29,12 +45,8 @@ static inline void no_context(struct pt_regs *regs, unsigned long addr) * Oops. The kernel tried to access some bad page. We'll have to * terminate things with extreme prejudice. */ - bust_spinlocks(1); - pr_alert("Unable to handle kernel %s at virtual address " REG_FMT "\n", - (addr < PAGE_SIZE) ? "NULL pointer dereference" : - "paging request", addr); - die(regs, "Oops"); - do_exit(SIGKILL); + msg = (addr < PAGE_SIZE) ? "NULL pointer dereference" : "paging request"; + die_kernel_fault(msg, addr, regs); } static inline void mm_fault_error(struct pt_regs *regs, unsigned long addr, vm_fault_t fault) @@ -202,6 +214,9 @@ asmlinkage void do_page_fault(struct pt_regs *regs) tsk = current; mm = tsk->mm; + if (kprobe_page_fault(regs, cause)) + return; + /* * Fault-in kernel-space virtual memory on-demand. * The 'reference' page table is init_mm.pgd. @@ -225,6 +240,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs) * in an atomic region, then we must not take the fault. */ if (unlikely(faulthandler_disabled() || !mm)) { + tsk->thread.bad_cause = cause; no_context(regs, addr); return; } @@ -232,6 +248,11 @@ asmlinkage void do_page_fault(struct pt_regs *regs) if (user_mode(regs)) flags |= FAULT_FLAG_USER; + if (!user_mode(regs) && addr < TASK_SIZE && + unlikely(!(regs->status & SR_SUM))) + die_kernel_fault("access to user memory without uaccess routines", + addr, regs); + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); if (cause == EXC_STORE_PAGE_FAULT) @@ -242,16 +263,19 @@ retry: mmap_read_lock(mm); vma = find_vma(mm, addr); if (unlikely(!vma)) { + tsk->thread.bad_cause = cause; bad_area(regs, mm, code, addr); return; } if (likely(vma->vm_start <= addr)) goto good_area; if (unlikely(!(vma->vm_flags & VM_GROWSDOWN))) { + tsk->thread.bad_cause = cause; bad_area(regs, mm, code, addr); return; } if (unlikely(expand_stack(vma, addr))) { + tsk->thread.bad_cause = cause; bad_area(regs, mm, code, addr); return; } @@ -264,6 +288,7 @@ good_area: code = SEGV_ACCERR; if (unlikely(access_error(cause, vma))) { + tsk->thread.bad_cause = cause; bad_area(regs, mm, code, addr); return; } @@ -297,6 +322,7 @@ good_area: mmap_read_unlock(mm); if (unlikely(fault & VM_FAULT_ERROR)) { + tsk->thread.bad_cause = cause; mm_fault_error(regs, addr, fault); return; } |