linux/arch/arm/mm
Mark Rutland f6d58ed718 ARM: 8356/1: mm: handle non-pmd-aligned end of RAM
commit 965278dcb8 upstream.

At boot time we round the memblock limit down to section size in an
attempt to ensure that we will have mapped this RAM with section
mappings prior to allocating from it. When mapping RAM we iterate over
PMD-sized chunks, creating these section mappings.

Section mappings are only created when the end of a chunk is aligned to
section size. Unfortunately, with classic page tables (where PMD_SIZE is
2 * SECTION_SIZE) this means that if a chunk is between 1M and 2M in
size the first 1M will not be mapped despite having been accounted for
in the memblock limit. This has been observed to result in page tables
being allocated from unmapped memory, causing boot-time hangs.

This patch modifies the memblock limit rounding to always round down to
PMD_SIZE instead of SECTION_SIZE. For classic MMU this means that we
will round the memblock limit down to a 2M boundary, matching the limits
on section mappings, and preventing allocations from unmapped memory.
For LPAE there should be no change as PMD_SIZE == SECTION_SIZE.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Stefan Agner <stefan@agner.ch>
Tested-by: Stefan Agner <stefan@agner.ch>
Acked-by: Laura Abbott <labbott@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
History 2015-06-03 13:27:20 +01:00
..
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: 8128/1: abort: don't clear the exclusive monitors 2014-10-05 13:41:01 -07:00
abort-ev7.S ARM: 8128/1: abort: don't clear the exclusive monitors 2014-10-05 13:41:01 -07:00
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: 8165/1: alignment: don't break misaligned NEON load/store 2014-10-05 13:41:02 -07:00
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: l2c: remove outer_inv_all() method 2014-05-22 16:21:35 +01:00
cache-l2x0.c ARM: l2c: fix revision checking 2014-07-07 17:55:22 +01:00
cache-nop.S ARM: Add base support for ARMv7-M 2013-04-17 21:38:10 +02:00
cache-tauros2.c ARM: cache-tauros2: remove ARMv6 code 2014-03-27 02:49:24 +01:00
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: 8055/1: cacheflush: use -st dsb option for ensuring completion 2014-05-25 23:47:46 +01:00
cache-xsc3l2.c ARM: move CP15 definitions to separate header file 2012-03-28 18:30:01 +01:00
context.c ARM: 8299/1: mm: ensure local active ASID is marked as allocated on rollover 2015-02-10 13:38:46 +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: ensure that old section mappings are flushed from the TLB 2014-07-17 19:26:08 +01:00
dump.c ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE 2014-12-04 09:42:17 +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: 8043/1: uprobes need icache flush after xol write 2014-05-25 23:48:45 +01:00
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 ARM: 8031/2: change fixmap mapping region to support 32 CPUs 2014-04-23 11:09:42 +01:00
hugetlbpage.c hugetlb: restrict hugepage_migration_support() to x86_64 2014-06-04 16:53:51 -07:00
idmap.c ARM: idmap: add identity mapping usage note 2014-08-02 15:20:26 +01:00
init.c Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next 2014-06-05 15:57:04 -07:00
iomap.c arm/PCI: remove arch pci_flags definition 2012-02-23 20:18:56 -07:00
ioremap.c ARM: 8060/1: mm: allow sub-architectures to override PCI I/O memory type 2014-06-01 01:15:04 +01:00
Kconfig ARM: 8198/1: make kuser helpers depend on MMU 2014-11-27 11:21:50 +00:00
l2c-common.c ARM: outer cache: add WARN_ON() to outer_disable() 2014-05-30 00:47:23 +01:00
l2c-l2x0-resume.S ARM: l2c: provide common PL310 early resume code 2014-05-30 00:49:01 +01:00
Makefile ARM: l2c: provide common PL310 early resume code 2014-05-30 00:49:01 +01:00
mm.h ARM: provide common method to clear bits in CPU control register 2014-06-02 09:20:11 +01:00
mmap.c ARM: fix booting low-vectors machines 2013-11-30 14:45:31 +00:00
mmu.c ARM: 8356/1: mm: handle non-pmd-aligned end of RAM 2015-06-03 13:27:20 +01:00
nommu.c ARM: 8086/1: Set memblock limit for nommu 2014-06-29 10:29:34 +01:00
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: arm925: ensure assembly sets up writethrough mapping 2014-06-20 11:23:02 +01:00
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 2014-02-10 11:48:13 +00:00
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 2014-02-10 11:48:13 +00:00
proc-v7-3level.S ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE 2014-12-04 09:42:17 +00:00
proc-v7.S ARM: 8222/1: mvebu: enable strex backoff delay 2014-12-10 17:15:41 +00:00
proc-v7m.S ARM: 8048/1: fix v7-M setup stack location 2014-05-25 23:44:24 +01:00
proc-xsc3.S arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
proc-xscale.S ARM: 8216/1: xscale: correct auxiliary register in suspend/resume 2014-12-10 17:15:01 +00:00
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