From 6456a2a69ee16ad402f26d272d0b67ce1d25061f Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Tue, 9 Feb 2021 18:33:43 -0800 Subject: [PATCH] x86/fault: Rename no_context() to kernelmode_fixup_or_oops() The name no_context() has never been very clear. It's only called for faults from kernel mode, so rename it and change the no-longer-useful user_mode(regs) check to a WARN_ON_ONCE. Signed-off-by: Andy Lutomirski Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/c21940efe676024bb4bc721f7d70c29c420e127e.1612924255.git.luto@kernel.org --- arch/x86/mm/fault.c | 28 ++++++++++------------------ 1 file changed, 10 insertions(+), 18 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 187975b1df66..3566a594e292 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -730,17 +730,10 @@ oops: } static noinline void -no_context(struct pt_regs *regs, unsigned long error_code, - unsigned long address, int signal, int si_code) +kernelmode_fixup_or_oops(struct pt_regs *regs, unsigned long error_code, + unsigned long address, int signal, int si_code) { - if (user_mode(regs)) { - /* - * This is an implicit supervisor-mode access from user - * mode. Bypass all the kernel-mode recovery code and just - * OOPS. - */ - goto oops; - } + WARN_ON_ONCE(user_mode(regs)); /* Are we prepared to handle this kernel fault? */ if (fixup_exception(regs, X86_TRAP_PF, error_code, address)) { @@ -780,7 +773,6 @@ no_context(struct pt_regs *regs, unsigned long error_code, if (is_prefetch(regs, error_code, address)) return; -oops: page_fault_oops(regs, error_code, address); } @@ -827,7 +819,7 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code, struct task_struct *tsk = current; if (!user_mode(regs)) { - no_context(regs, error_code, address, pkey, si_code); + kernelmode_fixup_or_oops(regs, error_code, address, pkey, si_code); return; } @@ -959,7 +951,7 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address, { /* Kernel mode? Handle exceptions or die: */ if (!user_mode(regs)) { - no_context(regs, error_code, address, SIGBUS, BUS_ADRERR); + kernelmode_fixup_or_oops(regs, error_code, address, SIGBUS, BUS_ADRERR); return; } @@ -1421,8 +1413,8 @@ good_area: * has unlocked the mm for us if we get here. */ if (!user_mode(regs)) - no_context(regs, error_code, address, SIGBUS, - BUS_ADRERR); + kernelmode_fixup_or_oops(regs, error_code, address, + SIGBUS, BUS_ADRERR); return; } @@ -1442,15 +1434,15 @@ good_area: return; if (fatal_signal_pending(current) && !user_mode(regs)) { - no_context(regs, error_code, address, 0, 0); + kernelmode_fixup_or_oops(regs, error_code, address, 0, 0); return; } if (fault & VM_FAULT_OOM) { /* Kernel mode? Handle exceptions or die: */ if (!user_mode(regs)) { - no_context(regs, error_code, address, - SIGSEGV, SEGV_MAPERR); + kernelmode_fixup_or_oops(regs, error_code, address, + SIGSEGV, SEGV_MAPERR); return; } -- 2.11.0