linux/arch/arm/mm
Will Deacon 10e9152881 ARM: 7954/1: mm: remove remaining domain support from ARMv6
commit b6ccb9803e upstream.

CPU_32v6 currently selects CPU_USE_DOMAINS if CPU_V6 and MMU. This is
because ARM 1136 r0pX CPUs lack the v6k extensions, and therefore do
not have hardware thread registers. The lack of these registers requires
the kernel to update the vectors page at each context switch in order to
write a new TLS pointer. This write must be done via the userspace
mapping, since aliasing caches can lead to expensive flushing when using
kmap. Finally, this requires the vectors page to be mapped r/w for
kernel and r/o for user, which has implications for things like put_user
which must trigger CoW appropriately when targetting user pages.

The upshot of all this is that a v6/v7 kernel makes use of domains to
segregate kernel and user memory accesses. This has the nasty
side-effect of making device mappings executable, which has been
observed to cause subtle bugs on recent cores (e.g. Cortex-A15
performing a speculative instruction fetch from the GIC and acking an
interrupt in the process).

This patch solves this problem by removing the remaining domain support
from ARMv6. A new memory type is added specifically for the vectors page
which allows that page (and only that page) to be mapped as user r/o,
kernel r/w. All other user r/o pages are mapped also as kernel r/o.
Patch co-developed with Russell King.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2014-05-06 07:59:22 -07:00
..
abort-ev4.S ARM: entry: data abort: tail-call the main data abort handler 2011-07-02 10:56:11 +01:00
abort-ev4t.S ARM: entry: data abort: tail-call the main data abort handler 2011-07-02 10:56:11 +01:00
abort-ev5t.S ARM: entry: data abort: tail-call the main data abort handler 2011-07-02 10:56:11 +01:00
abort-ev5tj.S ARM: entry: data abort: tail-call the main data abort handler 2011-07-02 10:56:11 +01:00
abort-ev6.S ARM: asm: Add ARM_BE8() assembly helper 2013-10-19 20:46:33 +01:00
abort-ev7.S ARM: entry: data abort: tail-call the main data abort handler 2011-07-02 10:56:11 +01:00
abort-lv4t.S ARM: entry: data abort: ensure r5 is preserved by abort functions 2011-07-02 10:56:12 +01:00
abort-macro.S ARM: 7088/1: entry: fix wrong parameter name used in do_thumb_abort 2011-09-10 23:39:56 +01:00
abort-nommu.S ARM: entry: data abort: tail-call the main data abort handler 2011-07-02 10:56:11 +01:00
alignment.c ARM: alignment: correctly decode instructions in BE8 mode. 2013-10-19 20:46:34 +01:00
cache-aurora-l2.h ARM: 7547/4: cache-l2x0: add support for Aurora L2 cache ctrl 2012-11-06 19:47:35 +00:00
cache-fa.S ARM: mm: implement LoUIS API for cache maintenance ops 2012-09-25 11:20:25 +01:00
cache-feroceon-l2.c ARM: 7696/1: Fix kexec by setting outer_cache.inv_all for Feroceon 2013-04-17 16:53:27 +01:00
cache-l2x0.c ARM: 7922/1: l2x0: add Marvell Tauros3 support 2013-12-29 12:32:47 +00:00
cache-nop.S ARM: Add base support for ARMv7-M 2013-04-17 21:38:10 +02:00
cache-tauros2.c ARM: cache: add dt support for tauros2 cache 2012-08-16 16:16:50 +08:00
cache-tauros3.h ARM: 7922/1: l2x0: add Marvell Tauros3 support 2013-12-29 12:32:47 +00:00
cache-v4.S ARM: mm: remove broken condition check for v4 flushing 2013-03-26 09:55:34 +00:00
cache-v4wb.S ARM: mm: implement LoUIS API for cache maintenance ops 2012-09-25 11:20:25 +01:00
cache-v4wt.S ARM: mm: implement LoUIS API for cache maintenance ops 2012-09-25 11:20:25 +01:00
cache-v6.S ARM: mm: implement LoUIS API for cache maintenance ops 2012-09-25 11:20:25 +01:00
cache-v7.S ARM: 7919/1: mm: refactor v7 cache cleaning ops to use way/index sequence 2013-12-29 12:32:40 +00:00
cache-xsc3l2.c ARM: move CP15 definitions to separate header file 2012-03-28 18:30:01 +01:00
context.c ARM: 7926/1: mm: flesh out and fix the comments in the ASID allocator 2013-12-29 12:46:49 +00:00
copypage-fa.c arm: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:14 +08:00
copypage-feroceon.c arm: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:14 +08:00
copypage-v4mc.c Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-03-29 16:53:48 -07:00
copypage-v4wb.c arm: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:14 +08:00
copypage-v4wt.c arm: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:14 +08:00
copypage-v6.c Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-03-29 16:53:48 -07:00
copypage-xsc3.c arm: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:14 +08:00
copypage-xscale.c Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-03-29 16:53:48 -07:00
dma-mapping.c ARM: dma-mapping: fix GFP_ATOMIC macro usage 2014-02-11 09:40:05 +01:00
dump.c ARM: 7963/1: mm: report both sections from PMD 2014-02-18 19:41:26 +00:00
extable.c ARM: 7876/1: clear Thumb-2 IT state on exception handling 2013-11-07 00:15:49 +00:00
fault-armv.c mm: rename USE_SPLIT_PTLOCKS to USE_SPLIT_PTE_PTLOCKS 2013-11-15 09:32:14 +09:00
fault.c arch: mm: pass userspace fault flag to generic fault handler 2013-09-12 15:38:01 -07:00
fault.h ARM: LPAE: Add fault handling support 2011-12-08 10:30:40 +00:00
flush.c ARM: 7923/1: mm: fix dcache flush logic for compound high pages 2013-12-29 12:46:08 +00:00
fsr-2level.c ARM: LPAE: Move the FSR definitions to separate files 2011-12-08 10:30:37 +00:00
fsr-3level.c ARM: mm: Transparent huge page support for LPAE systems. 2013-06-04 16:52:38 +01:00
highmem.c Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-03-29 16:53:48 -07:00
hugetlbpage.c mm: migrate: check movability of hugepage in unmap_and_move_huge_page() 2013-09-11 15:57:49 -07:00
idmap.c ARM: mm: Move the idmap print to appropriate place in the code 2013-10-10 20:25:06 -04:00
init.c Merge branches 'fixes' and 'misc' into for-linus 2014-01-28 21:38:48 +00:00
iomap.c arm/PCI: remove arch pci_flags definition 2012-02-23 20:18:56 -07:00
ioremap.c ARM: add permission annotations to MT_MEMORY* mapping types 2013-12-11 09:53:14 +00:00
Kconfig ARM: 7954/1: mm: remove remaining domain support from ARMv6 2014-05-06 07:59:22 -07:00
Makefile ARM: add support to dump the kernel page tables 2013-12-11 09:53:13 +00:00
mm.h ARM: 7950/1: mm: Fix stage-2 device memory attributes 2014-02-10 11:44:05 +00:00
mmap.c ARM: fix booting low-vectors machines 2013-11-30 14:45:31 +00:00
mmu.c ARM: 7954/1: mm: remove remaining domain support from ARMv6 2014-05-06 07:59:22 -07:00
nommu.c ARM: Fix nommu.c build warning 2013-11-14 10:59:50 +00:00
pabort-legacy.S ARM: entry: prefetch abort: tail-call the main prefetch abort handler 2011-07-02 10:56:10 +01:00
pabort-v6.S ARM: entry: prefetch abort: tail-call the main prefetch abort handler 2011-07-02 10:56:10 +01:00
pabort-v7.S ARM: entry: prefetch abort: tail-call the main prefetch abort handler 2011-07-02 10:56:10 +01:00
pgd.c ARM: pgd allocation: retry on failure 2013-12-29 12:36:20 +00:00
proc-arm7tdmi.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm9tdmi.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm720.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm740.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm920.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm922.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm925.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm926.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm940.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm946.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm1020.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm1020e.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm1022.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-arm1026.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-fa526.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-feroceon.S ARM: 7818/1: feroceon: Add suspend/resume operation 2013-08-20 00:12:52 +01:00
proc-macros.S ARM: 7954/1: mm: remove remaining domain support from ARMv6 2014-05-06 07:59:22 -07:00
proc-mohawk.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-sa110.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-sa1100.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-syms.c ARM: modules: don't export cpu_set_pte_ext when !MMU 2013-03-26 09:55:34 +00:00
proc-v6.S ARM: 7953/1: mm: ensure TLB invalidation is complete before enabling MMU 2014-02-10 11:44:26 +00:00
proc-v7-2level.S ARM: 7954/1: mm: remove remaining domain support from ARMv6 2014-05-06 07:59:22 -07:00
proc-v7-3level.S ARM: 7784/1: mm: ensure SMP alternates assemble to exactly 4 bytes with Thumb-2 2013-07-22 14:29:09 +01:00
proc-v7.S ARM: 7953/1: mm: ensure TLB invalidation is complete before enabling MMU 2014-02-10 11:44:26 +00:00
proc-v7m.S ARM: ARMv7-M: implement read_cpuid_ext 2013-05-17 11:44:40 +02:00
proc-xsc3.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-xscale.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
tcm.h ARM: 7694/1: ARM, TCM: initialize TCM in paging_init(), instead of setup_arch() 2013-04-17 16:53:24 +01:00
tlb-fa.S Merge branch 'devel-stable' into for-next 2011-07-22 23:09:07 +01:00
tlb-v4.S ARM: mm: tlb-v4: Use the new processor struct macros 2011-07-07 15:31:12 +01:00
tlb-v4wb.S ARM: mm: tlb-v4wb: Use the new processor struct macros 2011-07-07 15:31:12 +01:00
tlb-v4wbi.S ARM: mm: tlb-v4wbi: Use the new processor struct macros 2011-07-07 15:31:12 +01:00
tlb-v6.S Merge branch 'devel-stable' into for-next 2011-07-22 23:09:07 +01:00
tlb-v7.S ARM: mm: use inner-shareable barriers for TLB and user cache operations 2013-08-12 12:25:45 +01:00