diff options
Diffstat (limited to 'arch/x86/mm/fault.c')
| -rw-r--r-- | arch/x86/mm/fault.c | 58 |
1 files changed, 20 insertions, 38 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 667f1da36208..46df4c6aae46 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -28,6 +28,7 @@ #include <asm/mmu_context.h> /* vma_pkey() */ #include <asm/efi.h> /* efi_recover_from_page_fault()*/ #include <asm/desc.h> /* store_idt(), ... */ +#include <asm/cpu_entry_area.h> /* exception stack */ #define CREATE_TRACE_POINTS #include <asm/trace/exceptions.h> @@ -359,8 +360,6 @@ static noinline int vmalloc_fault(unsigned long address) if (!(address >= VMALLOC_START && address < VMALLOC_END)) return -1; - WARN_ON_ONCE(in_nmi()); - /* * Copy kernel mappings over when needed. This can also * happen within a race in page table update. In the later @@ -603,24 +602,9 @@ static void show_ldttss(const struct desc_ptr *gdt, const char *name, u16 index) name, index, addr, (desc.limit0 | (desc.limit1 << 16))); } -/* - * This helper function transforms the #PF error_code bits into - * "[PROT] [USER]" type of descriptive, almost human-readable error strings: - */ -static void err_str_append(unsigned long error_code, char *buf, unsigned long mask, const char *txt) -{ - if (error_code & mask) { - if (buf[0]) - strcat(buf, " "); - strcat(buf, txt); - } -} - static void show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long address) { - char err_txt[64]; - if (!oops_may_print()) return; @@ -644,31 +628,29 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad from_kuid(&init_user_ns, current_uid())); } - pr_alert("BUG: unable to handle kernel %s at %px\n", - address < PAGE_SIZE ? "NULL pointer dereference" : "paging request", - (void *)address); - - err_txt[0] = 0; - - /* - * Note: length of these appended strings including the separation space and the - * zero delimiter must fit into err_txt[]. - */ - err_str_append(error_code, err_txt, X86_PF_PROT, "[PROT]" ); - err_str_append(error_code, err_txt, X86_PF_WRITE, "[WRITE]"); - err_str_append(error_code, err_txt, X86_PF_USER, "[USER]" ); - err_str_append(error_code, err_txt, X86_PF_RSVD, "[RSVD]" ); - err_str_append(error_code, err_txt, X86_PF_INSTR, "[INSTR]"); - err_str_append(error_code, err_txt, X86_PF_PK, "[PK]" ); - - pr_alert("#PF error: %s\n", error_code ? err_txt : "[normal kernel read fault]"); + if (address < PAGE_SIZE && !user_mode(regs)) + pr_alert("BUG: kernel NULL pointer dereference, address: %px\n", + (void *)address); + else + pr_alert("BUG: unable to handle page fault for address: %px\n", + (void *)address); + + pr_alert("#PF: %s %s in %s mode\n", + (error_code & X86_PF_USER) ? "user" : "supervisor", + (error_code & X86_PF_INSTR) ? "instruction fetch" : + (error_code & X86_PF_WRITE) ? "write access" : + "read access", + user_mode(regs) ? "user" : "kernel"); + pr_alert("#PF: error_code(0x%04lx) - %s\n", error_code, + !(error_code & X86_PF_PROT) ? "not-present page" : + (error_code & X86_PF_RSVD) ? "reserved bit violation" : + (error_code & X86_PF_PK) ? "protection keys violation" : + "permissions violation"); if (!(error_code & X86_PF_USER) && user_mode(regs)) { struct desc_ptr idt, gdt; u16 ldtr, tr; - pr_alert("This was a system access from user code\n"); - /* * This can happen for quite a few reasons. The more obvious * ones are faults accessing the GDT, or LDT. Perhaps @@ -793,7 +775,7 @@ no_context(struct pt_regs *regs, unsigned long error_code, if (is_vmalloc_addr((void *)address) && (((unsigned long)tsk->stack - 1 - address < PAGE_SIZE) || address - ((unsigned long)tsk->stack + THREAD_SIZE) < PAGE_SIZE)) { - unsigned long stack = this_cpu_read(orig_ist.ist[DOUBLEFAULT_STACK]) - sizeof(void *); + unsigned long stack = __this_cpu_ist_top_va(DF) - sizeof(void *); /* * We're likely to be running with very little stack space * left. It's plausible that we'd hit this condition but |