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Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r--arch/x86/mm/fault.c55
1 files changed, 18 insertions, 37 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 06c089513d39..46df4c6aae46 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -360,8 +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
@@ -604,24 +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;
@@ -645,31 +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