linux-toradex.git/arch/arm/include/asm/pgtable.h, branch v3.2.74 Linux kernel for Apalis and Colibri modules ARM: mm: introduce present, faulting entries for PAGE_NONE 2014-04-30T15:23:19+00:00 Will Deacon will.deacon@arm.com 2012-09-01T04:22:12+00:00 960bd8ae3e6402a0409b11ed18a7ba9aaf69c3c5 commit 26ffd0d43b186b0d5186354da8714a1c2d360df0 upstream. PROT_NONE mappings apply the page protection attributes defined by _P000 which translate to PAGE_NONE for ARM. These attributes specify an XN, RDONLY pte that is inaccessible to userspace. However, on kernels configured without support for domains, such a pte *is* accessible to the kernel and can be read via get_user, allowing tasks to read PROT_NONE pages via syscalls such as read/write over a pipe. This patch introduces a new software pte flag, L_PTE_NONE, that is set to identify faulting, present entries. Signed-off-by: Will Deacon <will.deacon@arm.com> [bwh: Backported to 3.2 as dependency of commit b6ccb9803e90 ('ARM: 7954/1: mm: remove remaining domain support from ARMv6'): - Drop 3-level changes - Adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 26ffd0d43b186b0d5186354da8714a1c2d360df0 upstream.

PROT_NONE mappings apply the page protection attributes defined by _P000
which translate to PAGE_NONE for ARM. These attributes specify an XN,
RDONLY pte that is inaccessible to userspace. However, on kernels
configured without support for domains, such a pte *is* accessible to
the kernel and can be read via get_user, allowing tasks to read
PROT_NONE pages via syscalls such as read/write over a pipe.

This patch introduces a new software pte flag, L_PTE_NONE, that is set
to identify faulting, present entries.

Signed-off-by: Will Deacon <will.deacon@arm.com>
[bwh: Backported to 3.2 as dependency of commit b6ccb9803e90
 ('ARM: 7954/1: mm: remove remaining domain support from ARMv6'):
 - Drop 3-level changes
 - Adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: 7487/1: mm: avoid setting nG bit for user mappings that aren't present 2012-09-19T14:05:01+00:00 Will Deacon will.deacon@arm.com 2012-08-10T16:51:18+00:00 ed756add374b0742f00fae8ff74db2e0186c0c70 commit 47f1204329237a0f8655f5a9f14a38ac81946ca1 upstream. Swap entries are encoding in ptes such that !pte_present(pte) and pte_file(pte). The remaining bits of the descriptor are used to identify the swapfile and offset within it to the swap entry. When writing such a pte for a user virtual address, set_pte_at unconditionally sets the nG bit, which (in the case of LPAE) will corrupt the swapfile offset and lead to a BUG: [ 140.494067] swap_free: Unused swap offset entry 000763b4 [ 140.509989] BUG: Bad page map in process rs:main Q:Reg pte:0ec76800 pmd:8f92e003 This patch fixes the problem by only setting the nG bit for user mappings that are actually present. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 47f1204329237a0f8655f5a9f14a38ac81946ca1 upstream.

Swap entries are encoding in ptes such that !pte_present(pte) and
pte_file(pte). The remaining bits of the descriptor are used to identify
the swapfile and offset within it to the swap entry.

When writing such a pte for a user virtual address, set_pte_at
unconditionally sets the nG bit, which (in the case of LPAE) will
corrupt the swapfile offset and lead to a BUG:

[  140.494067] swap_free: Unused swap offset entry 000763b4
[  140.509989] BUG: Bad page map in process rs:main Q:Reg  pte:0ec76800 pmd:8f92e003

This patch fixes the problem by only setting the nG bit for user
mappings that are actually present.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: 7488/1: mm: use 5 bits for swapfile type encoding 2012-09-12T02:36:57+00:00 Will Deacon will.deacon@arm.com 2012-08-10T16:51:19+00:00 775152296f2a750ebefc58d35fe0479a679f6797 commit f5f2025ef3e2cdb593707cbf87378761f17befbe upstream. Page migration encodes the pfn in the offset field of a swp_entry_t. For LPAE, we support physical addresses of up to 36 bits (due to sparsemem limitations with the size of page flags), requiring 24 bits to represent a pfn. A further 3 bits are used to encode a swp_entry into a pte, leaving 5 bits for the type field. Furthermore, the core code defines MAX_SWAPFILES_SHIFT as 5, so the additional type bit does not get used. This patch reduces the width of the type field to 5 bits, allowing us to create up to 31 swapfiles of 64GB each. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit f5f2025ef3e2cdb593707cbf87378761f17befbe upstream.

Page migration encodes the pfn in the offset field of a swp_entry_t.
For LPAE, we support physical addresses of up to 36 bits (due to
sparsemem limitations with the size of page flags), requiring 24 bits
to represent a pfn. A further 3 bits are used to encode a swp_entry into
a pte, leaving 5 bits for the type field. Furthermore, the core code
defines MAX_SWAPFILES_SHIFT as 5, so the additional type bit does not
get used.

This patch reduces the width of the type field to 5 bits, allowing us
to create up to 31 swapfiles of 64GB each.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Merge branch 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm 2011-10-28T19:02:27+00:00 Linus Torvalds torvalds@linux-foundation.org 2011-10-28T19:02:27+00:00 1fdb24e969110fafea36d3b393bea438f702c87f * 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (178 commits) ARM: 7139/1: fix compilation with CONFIG_ARM_ATAG_DTB_COMPAT and large TEXT_OFFSET ARM: gic, local timers: use the request_percpu_irq() interface ARM: gic: consolidate PPI handling ARM: switch from NO_MACH_MEMORY_H to NEED_MACH_MEMORY_H ARM: mach-s5p64x0: remove mach/memory.h ARM: mach-s3c64xx: remove mach/memory.h ARM: plat-mxc: remove mach/memory.h ARM: mach-prima2: remove mach/memory.h ARM: mach-zynq: remove mach/memory.h ARM: mach-bcmring: remove mach/memory.h ARM: mach-davinci: remove mach/memory.h ARM: mach-pxa: remove mach/memory.h ARM: mach-ixp4xx: remove mach/memory.h ARM: mach-h720x: remove mach/memory.h ARM: mach-vt8500: remove mach/memory.h ARM: mach-s5pc100: remove mach/memory.h ARM: mach-tegra: remove mach/memory.h ARM: plat-tcc: remove mach/memory.h ARM: mach-mmp: remove mach/memory.h ARM: mach-cns3xxx: remove mach/memory.h ... Fix up mostly pretty trivial conflicts in: - arch/arm/Kconfig - arch/arm/include/asm/localtimer.h - arch/arm/kernel/Makefile - arch/arm/mach-shmobile/board-ap4evb.c - arch/arm/mach-u300/core.c - arch/arm/mm/dma-mapping.c - arch/arm/mm/proc-v7.S - arch/arm/plat-omap/Kconfig largely due to some CONFIG option renaming (ie CONFIG_PM_SLEEP -> CONFIG_ARM_CPU_SUSPEND for the arm-specific suspend code etc) and addition of NEED_MACH_MEMORY_H next to HAVE_IDE. 
* 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (178 commits)
  ARM: 7139/1: fix compilation with CONFIG_ARM_ATAG_DTB_COMPAT and large TEXT_OFFSET
  ARM: gic, local timers: use the request_percpu_irq() interface
  ARM: gic: consolidate PPI handling
  ARM: switch from NO_MACH_MEMORY_H to NEED_MACH_MEMORY_H
  ARM: mach-s5p64x0: remove mach/memory.h
  ARM: mach-s3c64xx: remove mach/memory.h
  ARM: plat-mxc: remove mach/memory.h
  ARM: mach-prima2: remove mach/memory.h
  ARM: mach-zynq: remove mach/memory.h
  ARM: mach-bcmring: remove mach/memory.h
  ARM: mach-davinci: remove mach/memory.h
  ARM: mach-pxa: remove mach/memory.h
  ARM: mach-ixp4xx: remove mach/memory.h
  ARM: mach-h720x: remove mach/memory.h
  ARM: mach-vt8500: remove mach/memory.h
  ARM: mach-s5pc100: remove mach/memory.h
  ARM: mach-tegra: remove mach/memory.h
  ARM: plat-tcc: remove mach/memory.h
  ARM: mach-mmp: remove mach/memory.h
  ARM: mach-cns3xxx: remove mach/memory.h
  ...

Fix up mostly pretty trivial conflicts in:
 - arch/arm/Kconfig
 - arch/arm/include/asm/localtimer.h
 - arch/arm/kernel/Makefile
 - arch/arm/mach-shmobile/board-ap4evb.c
 - arch/arm/mach-u300/core.c
 - arch/arm/mm/dma-mapping.c
 - arch/arm/mm/proc-v7.S
 - arch/arm/plat-omap/Kconfig
largely due to some CONFIG option renaming (ie CONFIG_PM_SLEEP ->
CONFIG_ARM_CPU_SUSPEND for the arm-specific suspend code etc) and
addition of NEED_MACH_MEMORY_H next to HAVE_IDE.
ARM: 7077/1: LPAE: Use a mask for physical addresses in page table entries 2011-10-06T14:40:06+00:00 Catalin Marinas catalin.marinas@arm.com 2011-09-05T16:52:36+00:00 d7c5d0dcffb3b5702d9477faceff4b8398e6fed0 With LPAE, the physical address mask is 40-bit while the page table entry is 64-bit. This patch introduces PHYS_MASK for the 2-level page table format, defined as ~0UL. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
With LPAE, the physical address mask is 40-bit while the page table
entry is 64-bit. This patch introduces PHYS_MASK for the 2-level page
table format, defined as ~0UL.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 7075/1: LPAE: Factor out 2-level page table definitions into separate files 2011-10-06T14:40:05+00:00 Catalin Marinas catalin.marinas@arm.com 2011-09-05T16:41:02+00:00 17f57211969bddca2e922299a2530b1c65ccabfa This patch moves page table definitions from asm/page.h, asm/pgtable.h and asm/ptgable-hwdef.h into corresponding *-2level* files. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
This patch moves page table definitions from asm/page.h, asm/pgtable.h
and asm/ptgable-hwdef.h into corresponding *-2level* files.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: mm: Add strongly ordered descriptor support. 2011-09-23T06:35:30+00:00 Santosh Shilimkar santosh.shilimkar@ti.com 2011-06-28T19:42:56+00:00 8fb54284ba6aa1f0d832ec015fde64ecf4bb0f4f On certain architectures, there might be a need to mark certain addresses with strongly ordered memory attributes to avoid ordering issues at the interconnect level. On OMAP4, the asynchronous bridge buffers can only be drained with strongly ordered accesses and hence the need to mark the memory strongly ordered. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Woodruff Richard <r-woodruff2@ti.com> Tested-by: Vishwanath BS <vishwanath.bs@ti.com> 
On certain architectures, there might be a need to mark certain
addresses with strongly ordered memory attributes to avoid ordering
issues at the interconnect level.

On OMAP4, the asynchronous bridge buffers can only be drained
with strongly ordered accesses and hence the need to mark the
memory strongly ordered.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Woodruff Richard <r-woodruff2@ti.com>
Tested-by: Vishwanath BS <vishwanath.bs@ti.com>
ARM: pgtable: add pud-level code 2011-02-21T19:24:14+00:00 Russell King rmk+kernel@arm.linux.org.uk 2010-11-21T16:27:49+00:00 516295e5ab4bf986865cfff856d484ec678e3b0b Add pud_offset() et.al. between the pgd and pmd code in preparation of using pgtable-nopud.h rather than 4level-fixup.h. This incorporates a fix from Jamie Iles <jamie@jamieiles.com> for uaccess_with_memcpy.c. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Add pud_offset() et.al. between the pgd and pmd code in preparation of
using pgtable-nopud.h rather than 4level-fixup.h.

This incorporates a fix from Jamie Iles <jamie@jamieiles.com> for
uaccess_with_memcpy.c.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 6672/1: LPAE: use phys_addr_t instead of unsigned long in mapping functions 2011-02-15T14:20:23+00:00 Will Deacon will.deacon@arm.com 2011-02-15T11:42:57+00:00 cae6292b653f5e3308bf2787a54b7dcd2cc7e2b3 The unsigned long datatype is not sufficient for mapping physical addresses >= 4GB. This patch ensures that the phys_addr_t datatype is used to represent physical addresses when converting from a PFN. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
The unsigned long datatype is not sufficient for mapping physical addresses
>= 4GB.

This patch ensures that the phys_addr_t datatype is used to represent physical
addresses when converting from a PFN.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pgtable: provide RDONLY page table bit rather than WRITE bit 2010-12-22T11:05:35+00:00 Russell King rmk+kernel@arm.linux.org.uk 2010-11-16T08:40:36+00:00 36bb94ba36f332de767cfaa3af6a5136435a3a9c Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>