From: Dmitry Vyukov <dvyu...@google.com>
KERN_CONT leads to split lines in kernel output
and complicates useful changes to printk like
printing context before each line.
Only acceptable use of continuations is basically
boot-time testing.
Get rid of it.
Also tidy up code around as asked by reviewers.
Signed-off-by: Dmitry Vyukov <dvyu...@google.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhat...@gmail.com>
---
Changes since v1:
- use pr_alert() instead of printk(KERN_ALERT)
Changes since v2:
- drop unnecessary parenthesis
- remove once used nx_warning and smep_warning
---
arch/x86/mm/fault.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 9a84a0d08727..a73575cacfd9 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -641,11 +641,6 @@ static int is_f00f_bug(struct pt_regs *regs, unsigned long
address)
return 0;
}
-static const char nx_warning[] = KERN_CRIT
-"kernel tried to execute NX-protected page - exploit attempt? (uid: %d)\n";
-static const char smep_warning[] = KERN_CRIT
-"unable to execute userspace code (SMEP?) (uid: %d)\n";
-
static void
show_fault_oops(struct pt_regs *regs, unsigned long error_code,
unsigned long address)
@@ -664,20 +659,18 @@ show_fault_oops(struct pt_regs *regs, unsigned long
error_code,
pte = lookup_address_in_pgd(pgd, address, &level);
if (pte && pte_present(*pte) && !pte_exec(*pte))
- printk(nx_warning, from_kuid(&init_user_ns,
current_uid()));
+ pr_crit("kernel tried to execute NX-protected page -
exploit attempt? (uid: %d)\n",
+ from_kuid(&init_user_ns, current_uid()));
if (pte && pte_present(*pte) && pte_exec(*pte) &&
(pgd_flags(*pgd) & _PAGE_USER) &&
(__read_cr4() & X86_CR4_SMEP))
- printk(smep_warning, from_kuid(&init_user_ns,
current_uid()));
+ pr_crit("unable to execute userspace code (SMEP?) (uid:
%d)\n",
+ from_kuid(&init_user_ns, current_uid()));
}
- printk(KERN_ALERT "BUG: unable to handle kernel ");
- if (address < PAGE_SIZE)
- printk(KERN_CONT "NULL pointer dereference");
- else
- printk(KERN_CONT "paging request");
-
- printk(KERN_CONT " at %px\n", (void *) address);
+ pr_alert("BUG: unable to handle kernel %s at %px\n",
+ address < PAGE_SIZE ? "NULL pointer dereference" :
+ "paging request", (void *) address);
dump_pagetable(address);
}
--
2.18.0.rc2.346.g013aa6912e-goog
