linux_dsm_epyc7002/arch/x86_64/mm
Linus Torvalds dbe3ed1c07 x86-64: page faults from user mode are always user faults
Randy Dunlap noticed an interesting "crashme" behaviour on his dual
Prescott Xeon setup, where he gets page faults with the error code
having a zero "user" bit, but the register state points back to user
mode.

This may be a CPU microcode buglet triggered by some strange instruction
pattern that crashme generates, and loading a microcode update seems to
possibly have fixed it.

Regardless, we really should trust the register state more than the
error code, since it's really the register state that determines whether
we can actually send a signal, or whether we're in kernel mode and need
to oops/kill the process in the case of a page fault.

Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-19 11:37:14 -07:00
..
extable.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
fault.c x86-64: page faults from user mode are always user faults 2007-09-19 11:37:14 -07:00
init.c Revert most of "x86: Fix alternatives and kprobes to remap write-protected kernel text" 2007-07-26 12:07:21 -07:00
ioremap.c Revert "[PATCH] x86: __pa and __pa_symbol address space separation" 2007-05-07 08:44:24 -07:00
k8topology.c x86_64: make k8topology multi-core aware 2007-07-21 18:37:14 -07:00
Makefile [PATCH] x86_64: Flexmap for 32bit and randomized mappings for 64bit 2006-01-16 23:18:35 -08:00
mmap.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
numa.c x86_64: disable srat when numa emulation succeeds 2007-07-21 18:37:14 -07:00
pageattr.c x86: Disable CLFLUSH support again 2007-08-11 15:58:13 -07:00
srat.c x86_64: fake apicid_to_node mapping for fake numa 2007-07-21 18:37:10 -07:00