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* ARM: 8494/1: mm: Enable PXN when running non-LPAE kernel on LPAE processorJungseung Lee2019-04-031-1/+1
| | | | | | | | | | | | | | | | | | [ Upstream commit ad84f56bf6d620fe6ed4d57ce6ec9945684d7f35 ] The VMSA field of MMFR0 (bottom 4 bits) is incremented for each added feature. PXN is supported if the value is >= 4 and LPAE is supported if it is >= 5. In case a kernel with CONFIG_ARM_LPAE disabled is used on a processor that supports LPAE, we can still use PXN in short descriptors. So check for >= 4 not == 4. Signed-off-by: Jungseung Lee <js07.lee@samsung.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ARM: 8814/1: mm: improve/fix ARM v7_dma_inv_range() unaligned address handlingChris Cole2018-12-211-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit a1208f6a822ac29933e772ef1f637c5d67838da9 ] This patch addresses possible memory corruption when v7_dma_inv_range(start_address, end_address) address parameters are not aligned to whole cache lines. This function issues "invalidate" cache management operations to all cache lines from start_address (inclusive) to end_address (exclusive). When start_address and/or end_address are not aligned, the start and/or end cache lines are first issued "clean & invalidate" operation. The assumption is this is done to ensure that any dirty data addresses outside the address range (but part of the first or last cache lines) are cleaned/flushed so that data is not lost, which could happen if just an invalidate is issued. The problem is that these first/last partial cache lines are issued "clean & invalidate" and then "invalidate". This second "invalidate" is not required and worse can cause "lost" writes to addresses outside the address range but part of the cache line. If another component writes to its part of the cache line between the "clean & invalidate" and "invalidate" operations, the write can get lost. This fix is to remove the extra "invalidate" operation when unaligned addressed are used. A kernel module is available that has a stress test to reproduce the issue and a unit test of the updated v7_dma_inv_range(). It can be downloaded from http://ftp.sageembedded.com/outgoing/linux/cache-test-20181107.tgz. v7_dma_inv_range() is call by dmac_[un]map_area(addr, len, direction) when the direction is DMA_FROM_DEVICE. One can (I believe) successfully argue that DMA from a device to main memory should use buffers aligned to cache line size, because the "clean & invalidate" might overwrite data that the device just wrote using DMA. But if a driver does use unaligned buffers, at least this fix will prevent memory corruption outside the buffer. Signed-off-by: Chris Cole <chris@sageembedded.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ARM: 8799/1: mm: fix pci_ioremap_io() offset checkThomas Petazzoni2018-11-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 3a58ac65e2d7969bcdf1b6acb70fa4d12a88e53e ] IO_SPACE_LIMIT is the ending address of the PCI IO space, i.e something like 0xfffff (and not 0x100000). Therefore, when offset = 0xf0000 is passed as argument, this function fails even though the offset + SZ_64K fits below the IO_SPACE_LIMIT. This makes the last chunk of 64 KB of the I/O space not usable as it cannot be mapped. This patch fixes that by substracing 1 to offset + SZ_64K, so that we compare the addrss of the last byte of the I/O space against IO_SPACE_LIMIT instead of the address of the first byte of what is after the I/O space. Fixes: c2794437091a4 ("ARM: Add fixed PCI i/o mapping") Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ARM: 8780/1: ftrace: Only set kernel memory back to read-only after bootSteven Rostedt (VMware)2018-08-241-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit b4c7e2bd2eb4764afe3af9409ff3b1b87116fa30 ] Dynamic ftrace requires modifying the code segments that are usually set to read-only. To do this, a per arch function is called both before and after the ftrace modifications are performed. The "before" function will set kernel code text to read-write to allow for ftrace to make the modifications, and the "after" function will set the kernel code text back to "read-only" to keep the kernel code text protected. The issue happens when dynamic ftrace is tested at boot up. The test is done before the kernel code text has been set to read-only. But the "before" and "after" calls are still performed. The "after" call will change the kernel code text to read-only prematurely, and other boot code that expects this code to be read-write will fail. The solution is to add a variable that is set when the kernel code text is expected to be converted to read-only, and make the ftrace "before" and "after" calls do nothing if that variable is not yet set. This is similar to the x86 solution from commit 162396309745 ("ftrace, x86: make kernel text writable only for conversions"). Link: http://lkml.kernel.org/r/20180620212906.24b7b66e@vmware.local.home Reported-by: Stefan Agner <stefan@agner.ch> Tested-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: dma-mapping: disallow dma_get_sgtable() for non-kernel managed memoryRussell King2017-12-251-1/+19
| | | | | | | | | | | | | | | | | | | | | [ Upstream commit 916a008b4b8ecc02fbd035cfb133773dba1ff3d7 ] dma_get_sgtable() tries to create a scatterlist table containing valid struct page pointers for the coherent memory allocation passed in to it. However, memory can be declared via dma_declare_coherent_memory(), or via other reservation schemes which means that coherent memory is not guaranteed to be backed by struct pages. In such cases, the resulting scatterlist table contains pointers to invalid pages, which causes kernel oops later. This patch adds detection of such memory, and refuses to create a scatterlist table for such memory. Reported-by: Shuah Khan <shuahkhan@gmail.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 8721/1: mm: dump: check hardware RO bit for LPAEPhilip Derrin2017-11-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3b0c0c922ff4be275a8beb87ce5657d16f355b54 upstream. When CONFIG_ARM_LPAE is set, the PMD dump relies on the software read-only bit to determine whether a page is writable. This concealed a bug which left the kernel text section writable (AP2=0) while marked read-only in the software bit. In a kernel with the AP2 bug, the dump looks like this: ---[ Kernel Mapping ]--- 0xc0000000-0xc0200000 2M RW NX SHD 0xc0200000-0xc0600000 4M ro x SHD 0xc0600000-0xc0800000 2M ro NX SHD 0xc0800000-0xc4800000 64M RW NX SHD The fix is to check that the software and hardware bits are both set before displaying "ro". The dump then shows the true perms: ---[ Kernel Mapping ]--- 0xc0000000-0xc0200000 2M RW NX SHD 0xc0200000-0xc0600000 4M RW x SHD 0xc0600000-0xc0800000 2M RW NX SHD 0xc0800000-0xc4800000 64M RW NX SHD Fixes: ded947798469 ("ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE") Signed-off-by: Philip Derrin <philip@cog.systems> Tested-by: Neil Dick <neil@cog.systems> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 8722/1: mm: make STRICT_KERNEL_RWX effective for LPAEPhilip Derrin2017-11-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 400eeffaffc7232c0ae1134fe04e14ae4fb48d8c upstream. Currently, for ARM kernels with CONFIG_ARM_LPAE and CONFIG_STRICT_KERNEL_RWX enabled, the 2MiB pages mapping the kernel code and rodata are writable. They are marked read-only in a software bit (L_PMD_SECT_RDONLY) but the hardware read-only bit is not set (PMD_SECT_AP2). For user mappings, the logic that propagates the software bit to the hardware bit is in set_pmd_at(); but for the kernel, section_update() writes the PMDs directly, skipping this logic. The fix is to set PMD_SECT_AP2 for read-only sections in section_update(), at the same time as L_PMD_SECT_RDONLY. Fixes: 1e3479225acb ("ARM: 8275/1: mm: fix PMD_SECT_RDONLY undeclared compile error") Signed-off-by: Philip Derrin <philip@cog.systems> Reported-by: Neil Dick <neil@cog.systems> Tested-by: Neil Dick <neil@cog.systems> Tested-by: Laura Abbott <labbott@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 8692/1: mm: abort uaccess retries upon fatal signalMark Rutland2017-09-131-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 746a272e44141af24a02f6c9b0f65f4c4598ed42 upstream. When there's a fatal signal pending, arm's do_page_fault() implementation returns 0. The intent is that we'll return to the faulting userspace instruction, delivering the signal on the way. However, if we take a fatal signal during fixing up a uaccess, this results in a return to the faulting kernel instruction, which will be instantly retried, resulting in the same fault being taken forever. As the task never reaches userspace, the signal is not delivered, and the task is left unkillable. While the task is stuck in this state, it can inhibit the forward progress of the system. To avoid this, we must ensure that when a fatal signal is pending, we apply any necessary fixup for a faulting kernel instruction. Thus we will return to an error path, and it is up to that code to make forward progress towards delivering the fatal signal. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 8685/1: ensure memblock-limit is pmd-alignedDoug Berger2017-07-051-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 9e25ebfe56ece7541cd10a20d715cbdd148a2e06 upstream. The pmd containing memblock_limit is cleared by prepare_page_table() which creates the opportunity for early_alloc() to allocate unmapped memory if memblock_limit is not pmd aligned causing a boot-time hang. Commit 965278dcb8ab ("ARM: 8356/1: mm: handle non-pmd-aligned end of RAM") attempted to resolve this problem, but there is a path through the adjust_lowmem_bounds() routine where if all memory regions start and end on pmd-aligned addresses the memblock_limit will be set to arm_lowmem_limit. Since arm_lowmem_limit can be affected by the vmalloc early parameter, the value of arm_lowmem_limit may not be pmd-aligned. This commit corrects this oversight such that memblock_limit is always rounded down to pmd-alignment. Fixes: 965278dcb8ab ("ARM: 8356/1: mm: handle non-pmd-aligned end of RAM") Signed-off-by: Doug Berger <opendmb@gmail.com> Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: larger stack guard gap, between vmasHugh Dickins2017-06-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream. Stack guard page is a useful feature to reduce a risk of stack smashing into a different mapping. We have been using a single page gap which is sufficient to prevent having stack adjacent to a different mapping. But this seems to be insufficient in the light of the stack usage in userspace. E.g. glibc uses as large as 64kB alloca() in many commonly used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX] which is 256kB or stack strings with MAX_ARG_STRLEN. This will become especially dangerous for suid binaries and the default no limit for the stack size limit because those applications can be tricked to consume a large portion of the stack and a single glibc call could jump over the guard page. These attacks are not theoretical, unfortunatelly. Make those attacks less probable by increasing the stack guard gap to 1MB (on systems with 4k pages; but make it depend on the page size because systems with larger base pages might cap stack allocations in the PAGE_SIZE units) which should cover larger alloca() and VLA stack allocations. It is obviously not a full fix because the problem is somehow inherent, but it should reduce attack space a lot. One could argue that the gap size should be configurable from userspace, but that can be done later when somebody finds that the new 1MB is wrong for some special case applications. For now, add a kernel command line option (stack_guard_gap) to specify the stack gap size (in page units). Implementation wise, first delete all the old code for stack guard page: because although we could get away with accounting one extra page in a stack vma, accounting a larger gap can break userspace - case in point, a program run with "ulimit -S -v 20000" failed when the 1MB gap was counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK and strict non-overcommit mode. Instead of keeping gap inside the stack vma, maintain the stack guard gap as a gap between vmas: using vm_start_gap() in place of vm_start (or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few places which need to respect the gap - mainly arch_get_unmapped_area(), and and the vma tree's subtree_gap support for that. Original-patch-by: Oleg Nesterov <oleg@redhat.com> Original-patch-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Tested-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [wt: backport to 4.11: adjust context] [wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide] [wt: backport to 4.4: adjust context ; drop ppc hugetlb_radix changes] Signed-off-by: Willy Tarreau <w@1wt.eu> [gkh: minor build fixes for 4.4] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 8642/1: LPAE: catch pending imprecise abort on unmaskAlexander Sverdlin2017-02-142-2/+6
| | | | | | | | | | | | | | | commit 97a98ae5b8acf08d07d972c087b2def060bc9b73 upstream. Asynchronous external abort is coded differently in DFSR with LPAE enabled. Fixes: 9254970c "ARM: 8447/1: catch pending imprecise abort on unmask". Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds2015-12-171-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm fixes from Dan Williams: - Two bug fixes for misuse of PAGE_MASK in scatterlist and dma-debug. These are tagged for -stable. The scatterlist impact is potentially corrupted dma addresses on HIGHMEM enabled platforms. - A minor locking fix for the NFIT hot-add implementation that is new in 4.4-rc. This would only trigger in the case a hot-add raced driver removal. * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: dma-debug: Fix dma_debug_entry offset calculation Revert "scatterlist: use sg_phys()" nfit: acpi_nfit_notify(): Do not leave device locked
| * Revert "scatterlist: use sg_phys()"Dan Williams2015-12-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit db0fa0cb0157 "scatterlist: use sg_phys()" did replacements of the form: phys_addr_t phys = page_to_phys(sg_page(s)); phys_addr_t phys = sg_phys(s) & PAGE_MASK; However, this breaks platforms where sizeof(phys_addr_t) > sizeof(unsigned long). Revert for 4.3 and 4.4 to make room for a combined helper in 4.5. Cc: <stable@vger.kernel.org> Cc: Jens Axboe <axboe@fb.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Fixes: db0fa0cb0157 ("scatterlist: use sg_phys()") Suggested-by: Joerg Roedel <joro@8bytes.org> Reported-by: Vitaly Lavrov <vel21ripn@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | ARM: 8471/1: need to save/restore arm register(r11) when it is corruptedAnson Huang2015-12-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In cpu_v7_do_suspend routine, r11 is used while it is NOT saved/restored, different compiler may have different usage of ARM general registers, so it may cause issues during calling cpu_v7_do_suspend. We meet kernel fault occurs when using GCC 4.8.3, r11 contains valid value before calling into cpu_v7_do_suspend, but when returned from this routine, r11 is corrupted and lead to kernel fault. Doing save/restore for those corrupted registers is a must in assemble code. Signed-off-by: Anson Huang <Anson.Huang@freescale.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Cc: <stable@vger.kernel.org> # v3.3+ Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | ARM: 8464/1: Update all mm structures with section adjustmentsLaura Abbott2015-12-041-30/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when updating section permissions to mark areas RO or NX, the only mm updated is current->mm. This is working off the assumption that there are no additional mm structures at the time. This may not always hold true. (Example: calling modprobe early will trigger a fork/exec). Ensure all mm structres get updated with the new section information. Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Laura Abbott <labbott@fedoraproject.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | ARM: 8465/1: mm: keep reserved ASIDs in sync with mm after multiple rolloversWill Deacon2015-12-021-12/+26
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Under some unusual context-switching patterns, it is possible to end up with multiple threads from the same mm running concurrently with different ASIDs: 1. CPU x schedules task t with mm p containing ASID a and generation g This task doesn't block and the CPU doesn't context switch. So: * per_cpu(active_asid, x) = {g,a} * p->context.id = {g,a} 2. Some other CPU generates an ASID rollover. The global generation is now (g + 1). CPU x is still running t, with no context switch and so per_cpu(reserved_asid, x) = {g,a} 3. CPU y schedules task t', which shares mm p with t. The generation mismatches, so we take the slowpath and hit the reserved ASID from CPU x. p is then updated so that p->context.id = {g + 1,a} 4. CPU y schedules some other task u, which has an mm != p. 5. Some other CPU generates *another* CPU rollover. The global generation is now (g + 2). CPU x is still running t, with no context switch and so per_cpu(reserved_asid, x) = {g,a}. 6. CPU y once again schedules task t', but now *fails* to hit the reserved ASID from CPU x because of the generation mismatch. This results in a new ASID being allocated, despite the fact that t is still running on CPU x with the same mm. Consequently, TLBIs (e.g. as a result of CoW) will not be synchronised between the two threads. This patch fixes the problem by updating all of the matching reserved ASIDs when we hit on the slowpath (i.e. in step 3 above). This keeps the reserved ASIDs in-sync with the mm and avoids the problem. Cc: <stable@vger.kernel.org> Reported-by: Tony Thompson <anthony.thompson@arm.com> 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>
* Merge tag 'armsoc-soc' of ↵Linus Torvalds2015-11-103-0/+566
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC platform updates from Olof Johansson: "New and/or improved SoC support for this release: Marvell Berlin: - Enable standard DT-based cpufreq - Add CPU hotplug support Freescale: - Ethernet init for i.MX7D - Suspend/resume support for i.MX6UL Allwinner: - Support for R8 chipset (used on NTC's $9 C.H.I.P board) Mediatek: - SMP support for some platforms Uniphier: - L2 support - Cleaned up SMP support, etc. plus a handful of other patches around above functionality, and a few other smaller changes" * tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (42 commits) ARM: uniphier: rework SMP operations to use trampoline code ARM: uniphier: add outer cache support Documentation: EXYNOS: Update bootloader interface on exynos542x ARM: mvebu: add broken-idle option ARM: orion5x: use mac_pton() helper ARM: at91: pm: at91_pm_suspend_in_sram() must be 8-byte aligned ARM: sunxi: Add R8 support ARM: digicolor: select pinctrl/gpio driver arm: berlin: add CPU hotplug support arm: berlin: use non-self-cleared reset register to reset cpu ARM: mediatek: add smp bringup code ARM: mediatek: enable gpt6 on boot up to make arch timer working soc: mediatek: Fix random hang up issue while kernel init soc: ti: qmss: make acc queue support optional in the driver soc: ti: add firmware file name as part of the driver Documentation: dt: soc: Add description for knav qmss driver ARM: S3C64XX: Use PWM lookup table for mach-smartq ARM: S3C64XX: Use PWM lookup table for mach-hmt ARM: S3C64XX: Use PWM lookup table for mach-crag6410 ARM: S3C64XX: Use PWM lookup table for smdk6410 ...
| * ARM: uniphier: add outer cache supportMasahiro Yamada2015-10-273-0/+566
| | | | | | | | | | | | | | | | | | | | This commit adds support for UniPhier outer cache controller. All the UniPhier SoCs are equipped with the L2 cache, while the L3 cache is currently only integrated on PH1-Pro5 SoC. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Olof Johansson <olof@lixom.net>
* | kmap_atomic_to_page() has no users, remove itNicolas Pitre2015-11-091-10/+0
| | | | | | | | | | | | | | | | | | Removal started in commit 5bbeed12bdc3 ("sparc32: drop unused kmap_atomic_to_page"). Let's do it across the whole tree. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm, page_alloc: distinguish between being unable to sleep, unwilling to ↵Mel Gorman2015-11-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sleep and avoiding waking kswapd __GFP_WAIT has been used to identify atomic context in callers that hold spinlocks or are in interrupts. They are expected to be high priority and have access one of two watermarks lower than "min" which can be referred to as the "atomic reserve". __GFP_HIGH users get access to the first lower watermark and can be called the "high priority reserve". Over time, callers had a requirement to not block when fallback options were available. Some have abused __GFP_WAIT leading to a situation where an optimisitic allocation with a fallback option can access atomic reserves. This patch uses __GFP_ATOMIC to identify callers that are truely atomic, cannot sleep and have no alternative. High priority users continue to use __GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify callers that want to wake kswapd for background reclaim. __GFP_WAIT is redefined as a caller that is willing to enter direct reclaim and wake kswapd for background reclaim. This patch then converts a number of sites o __GFP_ATOMIC is used by callers that are high priority and have memory pools for those requests. GFP_ATOMIC uses this flag. o Callers that have a limited mempool to guarantee forward progress clear __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall into this category where kswapd will still be woken but atomic reserves are not used as there is a one-entry mempool to guarantee progress. o Callers that are checking if they are non-blocking should use the helper gfpflags_allow_blocking() where possible. This is because checking for __GFP_WAIT as was done historically now can trigger false positives. Some exceptions like dm-crypt.c exist where the code intent is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to flag manipulations. o Callers that built their own GFP flags instead of starting with GFP_KERNEL and friends now also need to specify __GFP_KSWAPD_RECLAIM. The first key hazard to watch out for is callers that removed __GFP_WAIT and was depending on access to atomic reserves for inconspicuous reasons. In some cases it may be appropriate for them to use __GFP_HIGH. The second key hazard is callers that assembled their own combination of GFP flags instead of starting with something like GFP_KERNEL. They may now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless if it's missed in most cases as other activity will wake kswapd. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | uaccess: reimplement probe_kernel_address() using probe_kernel_read()Andrew Morton2015-11-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | probe_kernel_address() is basically the same as the (later added) probe_kernel_read(). The return value on EFAULT is a bit different: probe_kernel_address() returns number-of-bytes-not-copied whereas probe_kernel_read() returns -EFAULT. All callers have been checked, none cared. probe_kernel_read() can be overridden by the architecture whereas probe_kernel_address() cannot. parisc, blackfin and um do this, to insert additional checking. Hence this patch possibly fixes obscure bugs, although there are only two probe_kernel_address() callsites outside arch/. My first attempt involved removing probe_kernel_address() entirely and converting all callsites to use probe_kernel_read() directly, but that got tiresome. This patch shrinks mm/slab_common.o by 218 bytes. For a single probe_kernel_address() callsite. Cc: Steven Miao <realmz6@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branches 'fixes' and 'misc' into for-nextRussell King2015-10-295-12/+34
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| * ARM: 8447/1: catch pending imprecise abort on unmaskLucas Stach2015-10-193-1/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Install a non-faulting handler just before unmasking imprecise aborts and switch back to the regular one after unmasking is done. This catches any pending imprecise abort that the firmware/bootloader may have left behind that would normally crash the kernel at that point. As there are apparently a lot of bootlaoders out there that do such a thing it makes sense to handle it in the common startup code. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Tested-by: Tyler Baker <tyler.baker@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| * ARM: 8427/1: dma-mapping: add support for offset parameter in dma_mmap()Marek Szyprowski2015-10-031-0/+2
| | | | | | | | | | | | | | | | | | | | | | IOMMU-based dma_mmap() implementation lacked proper support for offset parameter used in mmap call (it always assumed that mapping starts from offset zero). This patch adds support for offset parameter to IOMMU-based implementation. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: stable@vger.kernel.org # v3.6+ Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| * ARM: 8426/1: dma-mapping: add missing range check in dma_mmap()Marek Szyprowski2015-10-031-0/+5
| | | | | | | | | | | | | | | | | | | | | | dma_mmap() function in IOMMU-based dma-mapping implementation lacked a check for valid range of mmap parameters (offset and buffer size), what might have caused access beyond the allocated buffer. This patch fixes this issue. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: stable@vger.kernel.org # v3.6+ Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| * ARM: remove user cmpxchg syscallRussell King2015-10-031-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark Brand reports that a NEEDS_SYSCALL_FOR_CMPXCHG enabled kernel would open a security hole in the ghost syscall used to implement cmpxchg, as it fails to validate the user pointer. However, in order for this option to be enabled, you'd need to be building a pre-ARMv6 kernel with SMP support. There is only one system known which fits that, which is an early ARM SMP FPGA implementation based on the ARM926T. In any case, the Kconfig does not allow SMP to be enabled for pre-ARMv6 systems. Moreover, even if NEEDS_SYSCALL_FOR_CMPXCHG were to be enabled, the kernel would not build as __ARM_NR_cmpxchg64 is not defined. The simple answer is to remove the buggy code. Reported-by: Mark Brand <markbrand@google.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| * ARM: 8422/1: enable imprecise aborts during early kernel startupLucas Stach2015-09-221-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds imprecise abort enable/disable macros and uses them to enable imprecise aborts early when starting the kernel. This helps in tracking down the real cause for such imprecise abort, as they are handled as soon as they occur. Until now those aborts would only be enabled when entering the userspace and as a consequence crash the first userspace process if any abort had been raised during kernel startup. Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com> Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | ARM: alignment: fix alignment handling for uaccess changesRussell King2015-09-241-5/+25
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jonathan Liu reports that the recent addition of CPU_SW_DOMAIN_PAN causes wpa_supplicant to die due to the following kernel oops: Unhandled fault: page domain fault (0x81b) at 0x001017a2 pgd = ee1b8000 [001017a2] *pgd=6ebee831, *pte=6c35475f, *ppte=6c354c7f Internal error: : 81b [#1] SMP ARM Modules linked in: rt2800usb rt2x00usb rt2800librt2x00lib crc_ccitt mac80211 CPU: 1 PID: 202 Comm: wpa_supplicant Not tainted 4.3.0-rc2 #1 Hardware name: Allwinner sun7i (A20) Family task: ec872f80 ti: ee364000 task.ti: ee364000 PC is at do_alignment_ldmstm+0x1d4/0x238 LR is at 0x0 pc : [<c001d1d8>] lr : [<00000000>] psr: 600c0113 sp : ee365e18 ip : 00000000 fp : 00000002 r10: 001017a2 r9 : 00000002 r8 : 001017aa r7 : ee365fb0 r6 : e8820018 r5 : 001017a2 r4 : 00000003 r3 : d49e30e0 r2 : 00000000 r1 : ee365fbc r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none[ 34.393106] Control: 10c5387d Table: 6e1b806a DAC: 00000051 Process wpa_supplicant (pid: 202, stack limit = 0xee364210) Stack: (0xee365e18 to 0xee366000) ... [<c001d1d8>] (do_alignment_ldmstm) from [<c001d510>] (do_alignment+0x1f0/0x904) [<c001d510>] (do_alignment) from [<c00092a0>] (do_DataAbort+0x38/0xb4) [<c00092a0>] (do_DataAbort) from [<c0013d7c>] (__dabt_usr+0x3c/0x40) Exception stack(0xee365fb0 to 0xee365ff8) 5fa0: 00000000 56c728c0 001017a2 d49e30e0 5fc0: 775448d2 597d4e74 00200800 7a9e1625 00802001 00000021 b6deec84 00000100 5fe0: 08020200 be9f4f20 0c0b0d0a b6d9b3e0 600c0010 ffffffff Code: e1a0a005 e1a0000c 1affffe8 e5913000 (e4ea3001) ---[ end trace 0acd3882fcfdf9dd ]--- This is caused by the alignment handler not being fixed up for the uaccess changes, and userspace issuing an unaligned LDM instruction. So, fix the problem by adding the necessary fixups. Reported-by: Jonathan Liu <net147@gmail.com> Tested-by: Jonathan Liu <net147@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds2015-09-191-1/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull ARM fixes from Russell King: "Three fixes and a resulting cleanup for -rc2: - Andre Przywara reported that he was seeing a warning with the new cast inside DMA_ERROR_CODE's definition, and fixed the incorrect use. - Doug Anderson noticed that kgdb causes a "scheduling while atomic" bug. - OMAP5 folk noticed that their Thumb-2 compiled X servers crashed when enabling support to cover ARMv6 CPUs due to a kernel bug leaking some conditional context into the signal handler" * 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: ARM: 8425/1: kgdb: Don't try to stop the machine when setting breakpoints ARM: 8437/1: dma-mapping: fix build warning with new DMA_ERROR_CODE definition ARM: get rid of needless #if in signal handling code ARM: fix Thumb2 signal handling when ARMv6 is enabled
| * ARM: 8437/1: dma-mapping: fix build warning with new DMA_ERROR_CODE definitionAndre Przywara2015-09-161-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 96231b2686b5: ("ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE") changed the definition of DMA_ERROR_CODE to use dma_addr_t, which makes the compiler barf on assigning this to an "int" variable on ARM with LPAE enabled: ************* In file included from /src/linux/include/linux/dma-mapping.h:86:0, from /src/linux/arch/arm/mm/dma-mapping.c:21: /src/linux/arch/arm/mm/dma-mapping.c: In function '__iommu_create_mapping': /src/linux/arch/arm/include/asm/dma-mapping.h:16:24: warning: overflow in implicit constant conversion [-Woverflow] #define DMA_ERROR_CODE (~(dma_addr_t)0x0) ^ /src/linux/arch/arm/mm/dma-mapping.c:1252:15: note: in expansion of macro DMA_ERROR_CODE' int i, ret = DMA_ERROR_CODE; ^ ************* Remove the actually unneeded initialization of "ret" in __iommu_create_mapping() and move the variable declaration inside the for-loop to make the scope of this variable more clear. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| * Merge branch 'uaccess' into fixesRussell King2015-09-119-15/+33
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* | | dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}Christoph Hellwig2015-09-101-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since 2009 we have a nice asm-generic header implementing lots of DMA API functions for architectures using struct dma_map_ops, but unfortunately it's still missing a lot of APIs that all architectures still have to duplicate. This series consolidates the remaining functions, although we still need arch opt outs for two of them as a few architectures have very non-standard implementations. This patch (of 5): The coherent DMA allocator works the same over all architectures supporting dma_map operations. This patch consolidates them and converges the minor differences: - the debug_dma helpers are now called from all architectures, including those that were previously missing them - dma_alloc_from_coherent and dma_release_from_coherent are now always called from the generic alloc/free routines instead of the ops dma-mapping-common.h always includes dma-coherent.h to get the defintions for them, or the stubs if the architecture doesn't support this feature - checks for ->alloc / ->free presence are removed. There is only one magic instead of dma_map_ops without them (mic_dma_ops) and that one is x86 only anyway. Besides that only x86 needs special treatment to replace a default devices if none is passed and tweak the gfp_flags. An optional arch hook is provided for that. [linux@roeck-us.net: fix build] [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds2015-09-0316-39/+187
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull ARM development updates from Russell King: "Included in this update: - moving PSCI code from ARM64/ARM to drivers/ - removal of some architecture internals from global kernel view - addition of software based "privileged no access" support using the old domains register to turn off the ability for kernel loads/stores to access userspace. Only the proper accessors will be usable. - addition of early fixup support for early console - re-addition (and reimplementation) of OMAP special interconnect barrier - removal of finish_arch_switch() - only expose cpuX/online in sysfs if hotpluggable - a number of code cleanups" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (41 commits) ARM: software-based priviledged-no-access support ARM: entry: provide uaccess assembly macro hooks ARM: entry: get rid of multiple macro definitions ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die() ARM: uaccess: provide uaccess_save_and_enable() and uaccess_restore() ARM: mm: improve do_ldrd_abort macro ARM: entry: ensure that IRQs are enabled when calling syscall_trace_exit() ARM: entry: efficiency cleanups ARM: entry: get rid of asm_trace_hardirqs_on_cond ARM: uaccess: simplify user access assembly ARM: domains: remove DOMAIN_TABLE ARM: domains: keep vectors in separate domain ARM: domains: get rid of manager mode for user domain ARM: domains: move initial domain setting value to asm/domains.h ARM: domains: provide domain_mask() ARM: domains: switch to keeping domain value in register ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE ARM: 8417/1: refactor bitops functions with BIT_MASK() and BIT_WORD() ARM: 8416/1: Feroceon: use of_iomap() to map register base ARM: 8415/1: early fixmap support for earlycon ...
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| *-----. \ \ Merge branches 'cleanup', 'fixes', 'misc', 'omap-barrier' and 'uaccess' into ↵Russell King2015-09-0319-68/+253
| |\ \ \ \ \ \ | | | |_|_|/ / | | |/| | | / | | | | | |/ for-linus
| | | | | * ARM: entry: provide uaccess assembly macro hooksRussell King2015-08-267-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide hooks into the kernel entry and exit paths to permit control of userspace visibility to the kernel. The intended use is: - on entry to kernel from user, uaccess_disable will be called to disable userspace visibility - on exit from kernel to user, uaccess_enable will be called to enable userspace visibility - on entry from a kernel exception, uaccess_save_and_disable will be called to save the current userspace visibility setting, and disable access - on exit from a kernel exception, uaccess_restore will be called to restore the userspace visibility as it was before the exception occurred. These hooks allows us to keep userspace visibility disabled for the vast majority of the kernel, except for localised regions where we want to explicitly access userspace. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | | | * ARM: mm: improve do_ldrd_abort macroRussell King2015-08-254-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Improve the do_ldrd_abort macro code - firstly, it inefficiently checks for the LDRD encoding by doing a multi-stage test of various bits. This can be simplified by generating a mask, bitmasking the instruction and then comparing the result. Secondly, we want to be able to test the result rather than branching to do_DataAbort, so remove the branch at the end and rename the macro to 'teq_ldrd' to reflect it's new usage. teq_ldrd macro returns 'eq' if the instruction was a LDRD. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | | | * ARM: domains: keep vectors in separate domainRussell King2015-08-212-2/+12
| | |_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Keep the machine vectors in its own domain to avoid software based user access control from making the vector code inaccessible, and thereby deadlocking the machine. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | | * ARM: add soc memory barrier extensionRussell King2015-07-251-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add an extension to the heavy barrier code to allow a SoC specific memory barrier function to be provided. This is needed for platforms where the interconnect has weak ordering, and thus needs assistance to ensure that memory writes are properly visible in the correct order to other parts of the system. Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Richard Woodruff <r-woodruff2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | | * ARM: move heavy barrier support out of lineRussell King2015-07-252-0/+15
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The existing memory barrier macro causes a significant amount of code to be inserted inline at every call site. For example, in gpio_set_irq_type(), we have this for mb(): c0344c08: f57ff04e dsb st c0344c0c: e59f8190 ldr r8, [pc, #400] ; c0344da4 <gpio_set_irq_type+0x230> c0344c10: e3590004 cmp r9, #4 c0344c14: e5983014 ldr r3, [r8, #20] c0344c18: 0a000054 beq c0344d70 <gpio_set_irq_type+0x1fc> c0344c1c: e3530000 cmp r3, #0 c0344c20: 0a000004 beq c0344c38 <gpio_set_irq_type+0xc4> c0344c24: e50b2030 str r2, [fp, #-48] ; 0xffffffd0 c0344c28: e50bc034 str ip, [fp, #-52] ; 0xffffffcc c0344c2c: e12fff33 blx r3 c0344c30: e51bc034 ldr ip, [fp, #-52] ; 0xffffffcc c0344c34: e51b2030 ldr r2, [fp, #-48] ; 0xffffffd0 c0344c38: e5963004 ldr r3, [r6, #4] Moving the outer_cache_sync() call out of line reduces the impact of the barrier: c0344968: f57ff04e dsb st c034496c: e35a0004 cmp sl, #4 c0344970: e50b2030 str r2, [fp, #-48] ; 0xffffffd0 c0344974: 0a000044 beq c0344a8c <gpio_set_irq_type+0x1b8> c0344978: ebf363dd bl c001d8f4 <arm_heavy_mb> c034497c: e5953004 ldr r3, [r5, #4] This should reduce the cache footprint of this code. Overall, this results in a reduction of around 20K in the kernel size: text data bss dec hex filename 10773970 667392 10369656 21811018 14ccf4a ../build/imx6/vmlinux-old 10754219 667392 10369656 21791267 14c8223 ../build/imx6/vmlinux-new Another advantage to this approach is that we can finally resolve the issue of SoCs which have their own memory barrier requirements within multiplatform kernels (such as OMAP.) Here, the bus interconnects need additional handling to ensure that writes become visible in the correct order (eg, between dma_map() operations, writes to DMA coherent memory, and MMIO accesses.) Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Richard Woodruff <r-woodruff2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | * ARM: 8416/1: Feroceon: use of_iomap() to map register baseMasahiro Yamada2015-08-181-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The chain of of_address_to_resource() and ioremap() can be replaced with of_iomap(). Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | * ARM: 8415/1: early fixmap support for earlyconStefan Agner2015-08-182-10/+84
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add early fixmap support, initially to support permanent, fixed mapping support for early console. A temporary, early pte is created which is migrated to a permanent mapping in paging_init. This is also needed since the attributes may change as the memory types are initialized. The 3MiB range of fixmap spans two pte tables, but currently only one pte is created for early fixmap support. Re-add FIX_KMAP_BEGIN to the index calculation in highmem.c since the index for kmap does not start at zero anymore. This reverts 4221e2e6b316 ("ARM: 8031/1: fixmap: remove FIX_KMAP_BEGIN and FIX_KMAP_END") to some extent. Cc: Mark Salter <msalter@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | * ARM: 8398/1: arm DMA: Fix allocation from CMA for coherent DMALorenzo Nava2015-08-041-9/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows the use of CMA for DMA coherent memory allocation. At the moment if the input parameter "is_coherent" is set to true the allocation is not made using the CMA, which I think is not the desired behaviour. The patch covers the allocation and free of memory for coherent DMA. Signed-off-by: Lorenzo Nava <lorenx4@gmail.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | * ARM: reduce visibility of dmac_* functionsRussell King2015-08-012-0/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The dmac_* functions are private to the ARM DMA API implementation, and should not be used by drivers. In order to discourage their use, remove their prototypes and macros from asm/*.h. We have to leave dmac_flush_range() behind as Exynos and MSM IOMMU code use these; once these sites are fixed, this can be moved also. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| | | * ARM: 8395/1: l2c: Add support for the "arm,shared-override" propertyGeert Uytterhoeven2015-07-101-0/+5
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "CoreLink Level 2 Cache Controller L2C-310", p. 2-15, section 2.3.2 Shareable attribute" states: "The default behavior of the cache controller with respect to the shareable attribute is to transform Normal Memory Non-cacheable transactions into: - cacheable no allocate for reads - write through no write allocate for writes." Depending on the system architecture, this may cause memory corruption in the presence of bus mastering devices (e.g. OHCI). To avoid such corruption, the default behavior can be disabled by setting the Shared Override bit in the Auxiliary Control register. Currently the Shared Override bit can be set only using C code: - by calling l2x0_init() directly, which is deprecated, - by setting/clearing the bit in the machine_desc.l2c_aux_val/mask fields, but using values differing from 0/~0 is also deprecated. Hence add support for an "arm,shared-override" device tree property for the l2c device node. By specifying this property, affected systems can indicate that non-cacheable transactions must not be transformed. Then, it's up to the OS to decide. The current behavior is to set the "shared attribute override enable" bit, as there may exist kernel linear mappings and cacheable aliases for the DMA buffers, even if CMA is enabled. See also commit 1a8e41cd672f894b ("ARM: 6395/1: VExpress: Set bit 22 in the PL310 (cache controller) AuxCtlr register"): "Clearing bit 22 in the PL310 Auxiliary Control register (shared attribute override enable) has the side effect of transforming Normal Shared Non-cacheable reads into Cacheable no-allocate reads. Coherent DMA buffers in Linux always have a Cacheable alias via the kernel linear mapping and the processor can speculatively load cache lines into the PL310 controller. With bit 22 cleared, Non-cacheable reads would unexpectedly hit such cache lines leading to buffer corruption." Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | | Merge branch 'for-4.3/sg' of git://git.kernel.dk/linux-blockLinus Torvalds2015-09-021-1/+1
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull SG updates from Jens Axboe: "This contains a set of scatter-gather related changes/fixes for 4.3: - Add support for limited chaining of sg tables even for architectures that do not set ARCH_HAS_SG_CHAIN. From Christoph. - Add sg chain support to target_rd. From Christoph. - Fixup open coded sg->page_link in crypto/omap-sham. From Christoph. - Fixup open coded crypto ->page_link manipulation. From Dan. - Also from Dan, automated fixup of manual sg_unmark_end() manipulations. - Also from Dan, automated fixup of open coded sg_phys() implementations. - From Robert Jarzmik, addition of an sg table splitting helper that drivers can use" * 'for-4.3/sg' of git://git.kernel.dk/linux-block: lib: scatterlist: add sg splitting function scatterlist: use sg_phys() crypto/omap-sham: remove an open coded access to ->page_link scatterlist: remove open coded sg_unmark_end instances crypto: replace scatterwalk_sg_chain with sg_chain target/rd: always chain S/G list scatterlist: allow limited chaining without ARCH_HAS_SG_CHAIN
| * | scatterlist: use sg_phys()Dan Williams2015-08-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Coccinelle cleanup to replace open coded sg to physical address translations. This is in preparation for introducing scatterlists that reference __pfn_t. // sg_phys.cocci: convert usage page_to_phys(sg_page(sg)) to sg_phys(sg) // usage: make coccicheck COCCI=sg_phys.cocci MODE=patch virtual patch @@ struct scatterlist *sg; @@ - page_to_phys(sg_page(sg)) + sg->offset + sg_phys(sg) @@ struct scatterlist *sg; @@ - page_to_phys(sg_page(sg)) + sg_phys(sg) & PAGE_MASK Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* | | ARM: invalidate L1 before enabling coherencyRussell King2015-07-171-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We must invalidate the L1 cache before enabling coherency, otherwise secondary CPUs can inject invalid cache lines into the coherent CPU cluster, which could then be migrated to other CPUs. This fixes a recent regression with SoCFPGA randomly failing to boot. Fixes: 02b4e2756e01 ("ARM: v7 setup function should invalidate L1 cache") Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | | ARM: 8404/1: dma-mapping: fix off-by-one error in bitmap size checkMarek Szyprowski2015-07-171-1/+1
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | nr_bitmaps member of mapping structure stores the number of already allocated bitmaps and it is interpreted as loop iterator (it starts from 0 not from 1), so a comparison against number of possible bitmap extensions should include this fact. This patch fixes this by changing the extension failure condition. This issue has been introduced by commit 4d852ef8c2544ce21ae41414099a7504c61164a0 ("arm: dma-mapping: Add support to extend DMA IOMMU mappings"). Reported-by: Hyungwon Hwang <human.hwang@samsung.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Hyungwon Hwang <human.hwang@samsung.com> Cc: stable@vger.kernel.org # v3.15+ Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | Merge branches 'fixes' and 'ioremap' into for-linusRussell King2015-07-0716-261/+450
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| * | ARM: io: convert ioremap*() to functionsRussell King2015-07-032-23/+49
| |/ | | | | | | | | | | | | | | | | Convert the ioremap*() preprocessor macros to real functions, moving them out of line. This allows us to kill off __arm_ioremap(), and __arm_iounmap() helpers, and remove __arm_ioremap_pfn_caller() from global view. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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