linux_dsm_epyc7002/arch
Nicholas Piggin a048a07d7f powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit
On some CPUs we can prevent a vulnerability related to store-to-load
forwarding by preventing store forwarding between privilege domains,
by inserting a barrier in kernel entry and exit paths.

This is known to be the case on at least Power7, Power8 and Power9
powerpc CPUs.

Barriers must be inserted generally before the first load after moving
to a higher privilege, and after the last store before moving to a
lower privilege, HV and PR privilege transitions must be protected.

Barriers are added as patch sections, with all kernel/hypervisor entry
points patched, and the exit points to lower privilge levels patched
similarly to the RFI flush patching.

Firmware advertisement is not implemented yet, so CPU flush types
are hard coded.

Thanks to Michal Suchánek for bug fixes and review.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-21 20:45:31 -07:00
..
alpha mm: introduce MAP_FIXED_NOREPLACE 2018-04-11 10:28:38 -07:00
arc kbuild: mark $(targets) as .SECONDARY and remove .PRECIOUS markers 2018-04-07 19:04:02 +09:00
arm Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm 2018-05-20 11:50:27 -07:00
arm64 ARM: SoC fixes for 4.17-rc 2018-05-19 19:56:15 -07:00
c6x c6x: pass endianness info to sparse 2018-04-10 09:58:58 -04:00
h8300
hexagon hexagon: export csum_partial_copy_nocheck 2018-05-01 15:49:50 -05:00
ia64 pci-v4.17-changes 2018-04-06 18:31:06 -07:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2018-04-09 09:15:46 -07:00
microblaze Microblaze patches for 4.17-rc1 2018-04-12 10:18:02 -07:00
mips MIPS: Fix ptrace(2) PTRACE_PEEKUSR and PTRACE_POKEUSR accesses to o32 FGRs 2018-05-14 23:54:25 +01:00
nds32 page cache: use xa_lock 2018-04-11 10:28:39 -07:00
nios2 nios2 update for v4.17-rc1 2018-04-11 16:02:18 -07:00
openrisc OpenRISC updates for v4.17 2018-04-15 12:27:58 -07:00
parisc parisc: Move setup_profiling_timer() out of init section 2018-05-18 16:21:49 +02:00
powerpc powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit 2018-05-21 20:45:31 -07:00
riscv RISC-V: build vdso-dummy.o with -no-pie 2018-04-24 10:54:46 -07:00
s390 s390/cpum_sf: ensure sample frequency of perf event attributes is non-zero 2018-05-08 15:56:36 +02:00
sh sh: switch to NO_BOOTMEM 2018-05-11 13:35:46 -04:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2018-04-30 13:27:16 -07:00
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2018-04-11 16:36:47 -07:00
unicore32 unicore32: turn flush_dcache_mmap_lock into a no-op 2018-04-11 10:28:39 -07:00
x86 Merge branch 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-05-21 11:23:26 -07:00
xtensa mm: introduce MAP_FIXED_NOREPLACE 2018-04-11 10:28:38 -07:00
.gitignore
Kconfig KASAN: prohibit KASAN+STRUCTLEAK combination 2018-05-11 17:28:45 -07:00