linux/arch/x86
Dave Hansen 164477c233 x86/mm: Clarify hardware vs. software "error_code"
We pass around a variable called "error_code" all around the page
fault code.  Sounds simple enough, especially since "error_code" looks
like it exactly matches the values that the hardware gives us on the
stack to report the page fault error code (PFEC in SDM parlance).

But, that's not how it works.

For part of the page fault handler, "error_code" does exactly match
PFEC.  But, during later parts, it diverges and starts to mean
something a bit different.

Give it two names for its two jobs.

The place it diverges is also really screwy.  It's only in a spot
where the hardware tells us we have kernel-mode access that occurred
while we were in usermode accessing user-controlled address space.
Add a warning in there.

Cc: x86@kernel.org
Cc: Jann Horn <jannh@google.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180928160220.4A2272C9@viggo.jf.intel.com
2018-10-09 16:51:15 +02:00
..
boot Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
configs
crypto crypto: x86/aegis,morus - Do not require OSXSAVE for SSE2 2018-09-14 14:08:27 +08:00
entry x86/vdso: Fix vDSO build if a retpoline is emitted 2018-08-20 18:04:41 +02:00
events perf/x86/intel: Add support/quirk for the MISPREDICT bit on Knights Landing CPUs 2018-09-10 10:03:01 +02:00
hyperv x86/hyper-v: rename ipi_arg_{ex,non_ex} structures 2018-09-20 00:51:42 +02:00
ia32 syscalls/x86: auto-create compat_sys_*() prototypes 2018-04-02 20:16:18 +02:00
include x86/mm/tlb: Add freed_tables element to flush_tlb_info 2018-10-09 16:51:12 +02:00
kernel x86/mm/tlb: Add freed_tables argument to flush_tlb_mm_range 2018-10-09 16:51:12 +02:00
kvm KVM: nVMX: Fix bad cleanup on error of get/set nested state IOCTLs 2018-09-20 18:54:08 +02:00
lib x86/nmi: Fix NMI uaccess race against CR3 switching 2018-08-31 17:08:22 +02:00
math-emu
mm x86/mm: Clarify hardware vs. software "error_code" 2018-10-09 16:51:15 +02:00
net bpf, x32: Fix regression caused by commit 24dea04767 2018-07-26 02:51:12 +02:00
oprofile
pci PCI: Make early dump functionality generic 2018-06-29 20:06:07 -05:00
platform x86/efi: Load fixmap GDT in efi_call_phys_epilog() before setting %cr3 2018-09-12 21:53:34 +02:00
power Power management updates for 4.19-rc1 2018-08-14 13:12:24 -07:00
purgatory kbuild: move bin2c back to scripts/ from scripts/basic/ 2018-07-18 01:18:05 +09:00
ras
realmode
tools x86/relocs: Add __end_rodata_aligned to S_REL 2018-08-09 20:42:07 +02:00
um Consolidation of Kconfig files by Christoph Hellwig. 2018-08-15 13:05:12 -07:00
video
xen xen: fixes for 4.19-rc5 2018-09-23 13:32:19 +02:00
.gitignore
Kbuild
Kconfig x86/mm/cpa: Add large page preservation statistics 2018-09-27 20:39:38 +02:00
Kconfig.cpu Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-03-25 07:36:02 -10:00
Kconfig.debug Kconfig: consolidate the "Kernel hacking" menu 2018-08-02 08:06:48 +09:00
Makefile x86: Allow generating user-space headers without a compiler 2018-08-31 17:08:22 +02:00
Makefile_32.cpu
Makefile.um kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00