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2023-10-10arm: Remove now superfluous sentinel elem from ctl_table arraysJoel Granados
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Removed the sentinel as well as the explicit size from ctl_isa_vars. The size is redundant as the initialization sets it. Changed insn_emulation->sysctl from a 2 element array of struct ctl_table to a simple struct. This has no consequence for the sysctl registration as it is forwarded as a pointer. Removed sentinel from sve_defatul_vl_table, sme_default_vl_table, tagged_addr_sysctl_table and armv8_pmu_sysctl_table. This removal is safe because register_sysctl_sz and register_sysctl use the array size in addition to checking for the sentinel. Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-08-15sysctl: Add size to register_sysctlJoel Granados
This commit adds table_size to register_sysctl in preparation for the removal of the sentinel elements in the ctl_table arrays (last empty markers). And though we do *not* remove any sentinels in this commit, we set things up by either passing the table_size explicitly or using ARRAY_SIZE on the ctl_table arrays. We replace the register_syctl function with a macro that will add the ARRAY_SIZE to the new register_sysctl_sz function. In this way the callers that are already using an array of ctl_table structs do not change. For the callers that pass a ctl_table array pointer, we pass the table_size to register_sysctl_sz instead of the macro. Signed-off-by: Joel Granados <j.granados@samsung.com> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-28arm64: armv8_deprecated: remove unnecessary (void*) conversionsYu Zhe
Pointer variables of void * type do not require type cast. Signed-off-by: Yu Zhe <yuzhe@nfschina.com> Link: https://lore.kernel.org/r/20230303025047.19717-1-yuzhe@nfschina.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-25arm64: armv8_deprecated: fix unused-function errorRen Zhijie
If CONFIG_SWP_EMULATION is not set and CONFIG_CP15_BARRIER_EMULATION is not set, aarch64-linux-gnu complained about unused-function : arch/arm64/kernel/armv8_deprecated.c:67:21: error: ‘aarch32_check_condition’ defined but not used [-Werror=unused-function] static unsigned int aarch32_check_condition(u32 opcode, u32 psr) ^~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors To fix this warning, modify aarch32_check_condition() with __maybe_unused. Fixes: 0c5f416219da ("arm64: armv8_deprecated: move aarch32 helper earlier") Signed-off-by: Ren Zhijie <renzhijie2@huawei.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20221124022429.19024-1-renzhijie2@huawei.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: armv8_deprecated: rework deprected instruction handlingMark Rutland
Support for deprecated instructions can be enabled or disabled at runtime. To handle this, the code in armv8_deprecated.c registers and unregisters undef_hooks, and makes cross CPU calls to configure HW support. This is rather complicated, and the synchronization required to make this safe ends up serializing the handling of instructions which have been trapped. This patch simplifies the deprecated instruction handling by removing the dynamic registration and unregistration, and changing the trap handling code to determine whether a handler should be invoked. This removes the need for dynamic list management, and simplifies the locking requirements, making it possible to handle trapped instructions entirely in parallel. Where changing the emulation state requires a cross-call, this is serialized by locally disabling interrupts, ensuring that the CPU is not left in an inconsistent state. To simplify sysctl management, each insn_emulation is given a separate sysctl table, permitting these to be registered separately. The core sysctl code will iterate over all of these when walking sysfs. I've tested this with userspace programs which use each of the deprecated instructions, and I've concurrently modified the support level for each of the features back-and-forth between HW and emulated to check that there are no spurious SIGILLs sent to userspace when the support level is changed. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-10-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: armv8_deprecated: move aarch32 helper earlierMark Rutland
Subsequent patches will rework the logic in armv8_deprecated.c. In preparation for subsequent changes, this patch moves some shared logic earlier in the file. This will make subsequent diffs simpler and easier to read. At the same time, drop the `__kprobes` annotation from aarch32_check_condition(), as this is only used for traps from compat userspace, and has no risk of recursion within kprobes. As this is the last kprobes annotation in armve8_deprecated.c, we no longer need to include <asm/kprobes.h>. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-9-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: armv8_deprecated move emulation functionsMark Rutland
Subsequent patches will rework the logic in armv8_deprecated.c. In preparation for subsequent changes, this patch moves the emulation logic earlier in the file, and moves the infrastructure later in the file. This will make subsequent diffs simpler and easier to read. This is purely a move. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-8-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: armv8_deprecated: fold ops into insn_emulationMark Rutland
The code for emulating deprecated instructions has two related structures: struct insn_emulation_ops and struct insn_emulation, where each struct insn_emulation_ops is associated 1-1 with a struct insn_emulation. It would be simpler to combine the two into a single structure, removing the need for (unconditional) dynamic allocation at boot time, and simplifying some runtime pointer chasing. This patch merges the two structures together. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-7-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-07-04arm64: fix oops in concurrently setting insn_emulation sysctlshaibinzhang (张海斌)
emulation_proc_handler() changes table->data for proc_dointvec_minmax and can generate the following Oops if called concurrently with itself: | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 | Internal error: Oops: 96000006 [#1] SMP | Call trace: | update_insn_emulation_mode+0xc0/0x148 | emulation_proc_handler+0x64/0xb8 | proc_sys_call_handler+0x9c/0xf8 | proc_sys_write+0x18/0x20 | __vfs_write+0x20/0x48 | vfs_write+0xe4/0x1d0 | ksys_write+0x70/0xf8 | __arm64_sys_write+0x20/0x28 | el0_svc_common.constprop.0+0x7c/0x1c0 | el0_svc_handler+0x2c/0xa0 | el0_svc+0x8/0x200 To fix this issue, keep the table->data as &insn->current_mode and use container_of() to retrieve the insn pointer. Another mutex is used to protect against the current_mode update but not for retrieving insn_emulation as table->data is no longer changing. Co-developed-by: hewenliang <hewenliang4@huawei.com> Signed-off-by: hewenliang <hewenliang4@huawei.com> Signed-off-by: Haibin Zhang <haibinzhang@tencent.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20220128090324.2727688-1-hewenliang4@huawei.com Link: https://lore.kernel.org/r/9A004C03-250B-46C5-BF39-782D7551B00E@tencent.com Signed-off-by: Will Deacon <will@kernel.org>
2021-10-21arm64: extable: add a dedicated uaccess handlerMark Rutland
For inline assembly, we place exception fixups out-of-line in the `.fixup` section such that these are out of the way of the fast path. This has a few drawbacks: * Since the fixup code is anonymous, backtraces will symbolize fixups as offsets from the nearest prior symbol, currently `__entry_tramp_text_end`. This is confusing, and painful to debug without access to the relevant vmlinux. * Since the exception handler adjusts the PC to execute the fixup, and the fixup uses a direct branch back into the function it fixes, backtraces of fixups miss the original function. This is confusing, and violates requirements for RELIABLE_STACKTRACE (and therefore LIVEPATCH). * Inline assembly and associated fixups are generated from templates, and we have many copies of logically identical fixups which only differ in which specific registers are written to and which address is branched to at the end of the fixup. This is potentially wasteful of I-cache resources, and makes it hard to add additional logic to fixups without significant bloat. This patch address all three concerns for inline uaccess fixups by adding a dedicated exception handler which updates registers in exception context and subsequent returns back into the function which faulted, removing the need for fixups specialized to each faulting instruction. Other than backtracing, there should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20211019160219.5202-12-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2020-12-02arm64: uaccess: rename privileged uaccess routinesMark Rutland
We currently have many uaccess_*{enable,disable}*() variants, which subsequent patches will cut down as part of removing set_fs() and friends. Once this simplification is made, most uaccess routines will only need to ensure that the user page tables are mapped in TTBR0, as is currently dealt with by uaccess_ttbr0_{enable,disable}(). The existing uaccess_{enable,disable}() routines ensure that user page tables are mapped in TTBR0, and also disable PAN protections, which is necessary to be able to use atomics on user memory, but also permit unrelated privileged accesses to access user memory. As preparatory step, let's rename uaccess_{enable,disable}() to uaccess_{enable,disable}_privileged(), highlighting this caveat and discouraging wider misuse. Subsequent patches can reuse the uaccess_{enable,disable}() naming for the common case of ensuring the user page tables are mapped in TTBR0. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20201202131558.39270-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-08arm64: armv8_deprecated: Fix undef_hook mask for thumb setendFredrik Strupe
For thumb instructions, call_undef_hook() in traps.c first reads a u16, and if the u16 indicates a T32 instruction (u16 >= 0xe800), a second u16 is read, which then makes up the the lower half-word of a T32 instruction. For T16 instructions, the second u16 is not read, which makes the resulting u32 opcode always have the upper half set to 0. However, having the upper half of instr_mask in the undef_hook set to 0 masks out the upper half of all thumb instructions - both T16 and T32. This results in trapped T32 instructions with the lower half-word equal to the T16 encoding of setend (b650) being matched, even though the upper half-word is not 0000 and thus indicates a T32 opcode. An example of such a T32 instruction is eaa0b650, which should raise a SIGILL since T32 instructions with an eaa prefix are unallocated as per Arm ARM, but instead works as a SETEND because the second half-word is set to b650. This patch fixes the issue by extending instr_mask to include the upper u32 half, which will still match T16 instructions where the upper half is 0, but not T32 instructions. Fixes: 2d888f48e056 ("arm64: Emulate SETEND for AArch32 tasks") Cc: <stable@vger.kernel.org> # 4.0.x- Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Fredrik Strupe <fredrik@strupe.net> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-17arm64: add blank after 'if'Zheng Wei
add blank after 'if' for armv8_deprecated_init() to make it comply with kernel coding style. Signed-off-by: Zheng Wei <wei.zheng@vivo.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-01-08arm64: armv8_deprecated: update the comments of armv8_deprecated_init()Hanjun Guo
In commit c0d8832e78cb ("arm64: Ensure the instruction emulation is ready for userspace"), armv8_deprecated_init() was promoted to core_initcall() but the comments were left unchanged, update it now. Spotted by some random reading of the code. Signed-off-by: Hanjun Guo <guohanjun@huawei.com> [will: "can guarantee" => "guarantees"] Signed-off-by: Will Deacon <will@kernel.org>
2019-10-08arm64: armv8_deprecated: Checking return value for memory allocationYunfeng Ye
There are no return value checking when using kzalloc() and kcalloc() for memory allocation. so add it. Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-03Remove 'type' argument from access_ok() functionLinus Torvalds
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-12arm64: kill config_sctlr_el1()Mark Rutland
Now that we have sysreg_clear_set(), we can consistently use this instead of config_sctlr_el1(). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05arm64: use PSR_AA32 definitionsMark Rutland
Some code cares about the SPSR_ELx format for exceptions taken from AArch32 to inspect or manipulate the SPSR_ELx value, which is already in the SPSR_ELx format, and not in the AArch32 PSR format. To separate these from cases where we care about the AArch32 PSR format, migrate these cases to use the PSR_AA32_* definitions rather than COMPAT_PSR_*. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-06-12treewide: kzalloc() -> kcalloc()Kees Cook
The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-05-15arm64: Remove duplicate includeVincenzo Frascino
"make includecheck" detected few duplicated includes in arch/arm64. This patch removes the double inclusions. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-03-06arm64: signal: Make force_signal_inject more robustWill Deacon
force_signal_inject is a little flakey: * It only knows about SIGILL and SIGSEGV, so can potentially deliver other signals based on a partially initialised siginfo_t * It sets si_addr to point at the PC for SIGSEGV * It always operates on current, so doesn't need the regs argument This patch fixes these issues by always assigning the si_addr field to the address parameter of the function and updates the callers (including those that indirectly call via arm64_notify_segfault) accordingly. Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-19arm64: uaccess: Formalise types for access_ok()Robin Murphy
In converting __range_ok() into a static inline, I inadvertently made it more type-safe, but without considering the ordering of the relevant conversions. This leads to quite a lot of Sparse noise about the fact that we use __chk_user_ptr() after addr has already been converted from a user pointer to an unsigned long. Rather than just adding another cast for the sake of shutting Sparse up, it seems reasonable to rework the types to make logical sense (although the resulting codegen for __range_ok() remains identical). The only callers this affects directly are our compat traps where the inferred "user-pointer-ness" of a register value now warrants explicit casting. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-11-15Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The big highlight is support for the Scalable Vector Extension (SVE) which required extensive ABI work to ensure we don't break existing applications by blowing away their signal stack with the rather large new vector context (<= 2 kbit per vector register). There's further work to be done optimising things like exception return, but the ABI is solid now. Much of the line count comes from some new PMU drivers we have, but they're pretty self-contained and I suspect we'll have more of them in future. Plenty of acronym soup here: - initial support for the Scalable Vector Extension (SVE) - improved handling for SError interrupts (required to handle RAS events) - enable GCC support for 128-bit integer types - remove kernel text addresses from backtraces and register dumps - use of WFE to implement long delay()s - ACPI IORT updates from Lorenzo Pieralisi - perf PMU driver for the Statistical Profiling Extension (SPE) - perf PMU driver for Hisilicon's system PMUs - misc cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (97 commits) arm64: Make ARMV8_DEPRECATED depend on SYSCTL arm64: Implement __lshrti3 library function arm64: support __int128 on gcc 5+ arm64/sve: Add documentation arm64/sve: Detect SVE and activate runtime support arm64/sve: KVM: Hide SVE from CPU features exposed to guests arm64/sve: KVM: Treat guest SVE use as undefined instruction execution arm64/sve: KVM: Prevent guests from using SVE arm64/sve: Add sysctl to set the default vector length for new processes arm64/sve: Add prctl controls for userspace vector length management arm64/sve: ptrace and ELF coredump support arm64/sve: Preserve SVE registers around EFI runtime service calls arm64/sve: Preserve SVE registers around kernel-mode NEON use arm64/sve: Probe SVE capabilities and usable vector lengths arm64: cpufeature: Move sys_caps_initialised declarations arm64/sve: Backend logic for setting the vector length arm64/sve: Signal handling support arm64/sve: Support vector length resetting for new processes arm64/sve: Core task context handling arm64/sve: Low-level CPU setup ...
2017-11-03arm64: Port deprecated instruction emulation to new sysctl interfaceDave Martin
Currently, armv8_deprected.c takes charge of the "abi" sysctl directory, which makes life difficult for other code that wants to register sysctls in the same directory. There is a "new" [1] sysctl registration interface that removes the need to define ctl_tables for parent directories explicitly, which is ideal here. This patch ports register_insn_emulation_sysctl() over to the register_sysctl() interface and removes the redundant ctl_table for "abi". Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> [1] fea478d4101a (sysctl: Add register_sysctl for normal sysctl users) The commit message notes an intent to port users of the pre-existing interfaces over to register_sysctl(), though the number of users of the new interface currently appears negligible. Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-25arm64: Fix single stepping in kernel trapsJulien Thierry
Software Step exception is missing after stepping a trapped instruction. Ensure SPSR.SS gets set to 0 after emulating/skipping a trapped instruction before doing ERET. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> [will: replaced AARCH32_INSN_SIZE with 4] Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-06arm64: Ensure the instruction emulation is ready for userspaceSuzuki K Poulose
We trap and emulate some instructions (e.g, mrs, deprecated instructions) for the userspace. However the handlers for these are registered as late_initcalls and the userspace could be up and running from the initramfs by that time (with populate_rootfs, which is a rootfs_initcall()). This could cause problems for the early applications ending up in failure like : [ 11.152061] modprobe[93]: undefined instruction: pc=0000ffff8ca48ff4 This patch promotes the specific calls to core_initcalls, which are guaranteed to be completed before we hit userspace. Cc: stable@vger.kernel.org Cc: Dave Martin <dave.martin@arm.com> Cc: Matthias Brugger <mbrugger@suse.com> Cc: James Morse <james.morse@arm.com> Reported-by: Matwey V. Kornilov <matwey.kornilov@gmail.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-09arm64: armv8_deprecated: ensure extension of addrMark Rutland
Our compat swp emulation holds the compat user address in an unsigned int, which it passes to __user_swpX_asm(). When a 32-bit value is passed in a register, the upper 32 bits of the register are unknown, and we must extend the value to 64 bits before we can use it as a base address. This patch casts the address to unsigned long to ensure it has been suitably extended, avoiding the potential issue, and silencing a related warning from clang. Fixes: bd35a4adc413 ("arm64: Port SWP/SWPB emulation support from arm") Cc: <stable@vger.kernel.org> # 3.19.x- Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-02-27kprobes: move kprobe declarations to asm-generic/kprobes.hLuis R. Rodriguez
Often all is needed is these small helpers, instead of compiler.h or a full kprobes.h. This is important for asm helpers, in fact even some asm/kprobes.h make use of these helpers... instead just keep a generic asm file with helpers useful for asm code with the least amount of clutter as possible. Likewise we need now to also address what to do about this file for both when architectures have CONFIG_HAVE_KPROBES, and when they do not. Then for when architectures have CONFIG_HAVE_KPROBES but have disabled CONFIG_KPROBES. Right now most asm/kprobes.h do not have guards against CONFIG_KPROBES, this means most architecture code cannot include asm/kprobes.h safely. Correct this and add guards for architectures missing them. Additionally provide architectures that not have kprobes support with the default asm-generic solution. This lets us force asm/kprobes.h on the header include/linux/kprobes.h always, but most importantly we can now safely include just asm/kprobes.h on architecture code without bringing the full kitchen sink of header files. Two architectures already provided a guard against CONFIG_KPROBES on its kprobes.h: sh, arch. The rest of the architectures needed gaurds added. We avoid including any not-needed headers on asm/kprobes.h unless kprobes have been enabled. In a subsequent atomic change we can try now to remove compiler.h from include/linux/kprobes.h. During this sweep I've also identified a few architectures defining a common macro needed for both kprobes and ftrace, that of the definition of the breakput instruction up. Some refer to this as BREAKPOINT_INSTRUCTION. This must be kept outside of the #ifdef CONFIG_KPROBES guard. [mcgrof@kernel.org: fix arm64 build] Link: http://lkml.kernel.org/r/CAB=NE6X1WMByuARS4mZ1g9+W=LuVBnMDnh_5zyN0CLADaVh=Jw@mail.gmail.com [sfr@canb.auug.org.au: fixup for kprobes declarations moving] Link: http://lkml.kernel.org/r/20170214165933.13ebd4f4@canb.auug.org.au Link: http://lkml.kernel.org/r/20170203233139.32682-1-mcgrof@kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-10arm64: add missing printk newlinesMark Rutland
A few printk calls in arm64 omit a trailing newline, even though there is no subsequent KERN_CONT printk associated with them, and we actually want a newline. This can result in unrelated lines being appended, rather than appearing on a new line. Additionally, timestamp prefixes may appear in-line. This makes the logs harder to read than necessary. Avoid this by adding a trailing newline. These were found with a shortlist generated by: $ git grep 'pr\(intk\|_.*\)(.*)' -- arch/arm64 | grep -v pr_fmt | grep -v '\\n"' Signed-off-by: Mark Rutland <mark.rutland@arm.com> CC: James Morse <james.morse@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-12-25Merge branch 'smp-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull SMP hotplug notifier removal from Thomas Gleixner: "This is the final cleanup of the hotplug notifier infrastructure. The series has been reintgrated in the last two days because there came a new driver using the old infrastructure via the SCSI tree. Summary: - convert the last leftover drivers utilizing notifiers - fixup for a completely broken hotplug user - prevent setup of already used states - removal of the notifiers - treewide cleanup of hotplug state names - consolidation of state space There is a sphinx based documentation pending, but that needs review from the documentation folks" * 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/armada-xp: Consolidate hotplug state space irqchip/gic: Consolidate hotplug state space coresight/etm3/4x: Consolidate hotplug state space cpu/hotplug: Cleanup state names cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions staging/lustre/libcfs: Convert to hotplug state machine scsi/bnx2i: Convert to hotplug state machine scsi/bnx2fc: Convert to hotplug state machine cpu/hotplug: Prevent overwriting of callbacks x86/msr: Remove bogus cleanup from the error path bus: arm-ccn: Prevent hotplug callback leak perf/x86/intel/cstate: Prevent hotplug callback leak ARM/imx/mmcd: Fix broken cpu hotplug handling scsi: qedi: Convert to hotplug state machine
2016-12-25cpu/hotplug: Cleanup state namesThomas Gleixner
When the state names got added a script was used to add the extra argument to the calls. The script basically converted the state constant to a string, but the cleanup to convert these strings into meaningful ones did not happen. Replace all the useless strings with 'subsys/xxx/yyy:state' strings which are used in all the other places already. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-02arm64: Get rid of asm/opcodes.hMarc Zyngier
The opcodes.h drags in a lot of definition from the 32bit port, most of which is not required at all. Clean things up a bit by moving the bare minimum of what is required next to the actual users, and drop the include file. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-21arm64: Factor out PAN enabling/disabling into separate uaccess_* macrosCatalin Marinas
This patch moves the directly coded alternatives for turning PAN on/off into separate uaccess_{enable,disable} macros or functions. The asm macros take a few arguments which will be used in subsequent patches. Note that any (unlikely) access that the compiler might generate between uaccess_enable() and uaccess_disable(), other than those explicitly specified by the user access code, will not be protected by PAN. Cc: Will Deacon <will.deacon@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-10-19arm64: swp emulation: bound LL/SC retries before reschedulingWill Deacon
If a CPU does not implement a global monitor for certain memory types, then userspace can attempt a kernel DoS by issuing SWP instructions targetting the problematic memory (for example, a framebuffer mapped with non-cacheable attributes). The SWP emulation code protects against these sorts of attacks by checking for pending signals and potentially rescheduling when the STXR instruction fails during the emulation. Whilst this is good for avoiding livelock, it harms emulation of legitimate SWP instructions on CPUs where forward progress is not guaranteed if there are memory accesses to the same reservation granule (up to 2k) between the failing STXR and the retry of the LDXR. This patch solves the problem by retrying the STXR a bounded number of times (4) before breaking out of the LL/SC loop and looking for something else to do. Cc: <stable@vger.kernel.org> Fixes: bd35a4adc413 ("arm64: Port SWP/SWPB emulation support from arm") Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-29Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp hotplug updates from Thomas Gleixner: "This is the next part of the hotplug rework. - Convert all notifiers with a priority assigned - Convert all CPU_STARTING/DYING notifiers The final removal of the STARTING/DYING infrastructure will happen when the merge window closes. Another 700 hundred line of unpenetrable maze gone :)" * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) timers/core: Correct callback order during CPU hot plug leds/trigger/cpu: Move from CPU_STARTING to ONLINE level powerpc/numa: Convert to hotplug state machine arm/perf: Fix hotplug state machine conversion irqchip/armada: Avoid unused function warnings ARC/time: Convert to hotplug state machine clocksource/atlas7: Convert to hotplug state machine clocksource/armada-370-xp: Convert to hotplug state machine clocksource/exynos_mct: Convert to hotplug state machine clocksource/arm_global_timer: Convert to hotplug state machine rcu: Convert rcutree to hotplug state machine KVM/arm/arm64/vgic-new: Convert to hotplug state machine smp/cfd: Convert core to hotplug state machine x86/x2apic: Convert to CPU hotplug state machine profile: Convert to hotplug state machine timers/core: Convert to hotplug state machine hrtimer: Convert to hotplug state machine x86/tboot: Convert to hotplug state machine arm64/armv8 deprecated: Convert to hotplug state machine hwtracing/coresight-etm4x: Convert to hotplug state machine ...
2016-07-21Merge branch 'for-next/kprobes' into for-next/coreCatalin Marinas
* kprobes: arm64: kprobes: Add KASAN instrumentation around stack accesses arm64: kprobes: Cleanup jprobe_return arm64: kprobes: Fix overflow when saving stack arm64: kprobes: WARN if attempting to step with PSTATE.D=1 kprobes: Add arm64 case in kprobe example module arm64: Add kernel return probes support (kretprobes) arm64: Add trampoline code for kretprobes arm64: kprobes instruction simulation support arm64: Treat all entry code as non-kprobe-able arm64: Blacklist non-kprobe-able symbol arm64: Kprobes with single stepping support arm64: add conditional instruction simulation support arm64: Add more test functions to insn.c arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature
2016-07-19arm64: add conditional instruction simulation supportDavid A. Long
Cease using the arm32 arm_check_condition() function and replace it with a local version for use in deprecated instruction support on arm64. Also make the function table used by this available for future use by kprobes and/or uprobes. This function is derived from code written by Sandeepa Prabhu. Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com> Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-15arm64/armv8 deprecated: Convert to hotplug state machineSebastian Andrzej Siewior
Install the callbacks via the state machine. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Jisheng Zhang <jszhang@marvell.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Shengjiu Wang <shengjiu.wang@freescale.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153337.311115906@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-01arm64: consolidate signal injection on emulation errorsAndre Przywara
The code for injecting a signal into userland if a trapped instruction fails emulation due to a _userland_ error (like an illegal address) will be used more often with the next patch. Factor out the core functionality into a separate function and use that both for the existing trap handler and for the deprecated instructions emulation. Signed-off-by: Andre Przywara <andre.przywara@arm.com> [catalin.marinas@arm.com: s/set_segfault/arm64_notify_segfault/] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24arm64: switch to relative exception tablesArd Biesheuvel
Instead of using absolute addresses for both the exception location and the fixup, use offsets relative to the exception table entry values. Not only does this cut the size of the exception table in half, it is also a prerequisite for KASLR, since absolute exception table entries are subject to dynamic relocation, which is incompatible with the sorting of the exception table that occurs at build time. This patch also introduces the _ASM_EXTABLE preprocessor macro (which exists on x86 as well) and its _asm_extable assembly counterpart, as shorthands to emit exception table entries. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-12-02arm64: add __init/__initdata section marker to some functions/variablesJisheng Zhang
These functions/variables are not needed after booting, so mark them as __init or __initdata. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-28arm64: compat: fix stxr failure case in SWP emulationWill Deacon
If the STXR instruction fails in the SWP emulation code, we leave *data overwritten with the loaded value, therefore corrupting the data written by a subsequent, successful attempt. This patch re-jigs the code so that we only write back to *data once we know that the update has happened. Cc: <stable@vger.kernel.org> Fixes: bd35a4adc413 ("arm64: Port SWP/SWPB emulation support from arm") Reported-by: Shengjiu Wang <shengjiu.wang@freescale.com> Reported-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: kernel: Add support for Privileged Access NeverJames Morse
'Privileged Access Never' is a new arm8.1 feature which prevents privileged code from accessing any virtual address where read or write access is also permitted at EL0. This patch enables the PAN feature on all CPUs, and modifies {get,put}_user helpers temporarily to permit access. This will catch kernel bugs where user memory is accessed directly. 'Unprivileged loads and stores' using ldtrb et al are unaffected by PAN. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: James Morse <james.morse@arm.com> [will: use ALTERNATIVE in asm and tidy up pan_enable check] Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: kernel: Move config_sctlr_el1James Morse
Later patches need config_sctlr_el1 to set/clear bits in the sctlr_el1 register. This patch moves this function into header a file. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-23arm64: Emulate SETEND for AArch32 tasksSuzuki K. Poulose
Emulate deprecated 'setend' instruction for AArch32 bit tasks. setend [le/be] - Sets the endianness of EL0 On systems with CPUs which support mixed endian at EL0, the hardware support for the instruction can be enabled by setting the SCTLR_EL1.SED bit. Like the other emulated instructions it is controlled by an entry in /proc/sys/abi/. For more information see : Documentation/arm64/legacy_instructions.txt The instruction is emulated by setting/clearing the SPSR_EL1.E bit, which will be reflected in the PSTATE.E in AArch32 context. This patch also restores the native endianness for the execution of signal handlers, since the process could have changed the endianness. Note: All CPUs on the system must have mixed endian support at EL0. Once the handler is registered, hotplugging a CPU which doesn't support mixed endian, could lead to unexpected results/behavior in applications. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-23arm64: Consolidate hotplug notifier for instruction emulationSuzuki K. Poulose
As of now each insn_emulation has a cpu hotplug notifier that enables/disables the CPU feature bit for the functionality. This patch re-arranges the code, such that there is only one notifier that runs through the list of registered emulation hooks and runs their corresponding set_hw_mode. We do nothing when a CPU is dying as we will set the appropriate bits as it comes back online based on the state of the hooks. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Punit Agrawal <punit.agrawal@arm.com> [catalin.marinas@arm.com: fix pr_warn compilation error] [catalin.marinas@arm.com: remove unnecessary "insn" check] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-11-25arm64: fix return code check when changing emulation handlerWill Deacon
update_insn_emulation_mode() returns 0 on success, so we should be treating any non-zero values as failure, rather than the other way around. Otherwise, writes to the sysctl file controlling the emulation are ignored and immediately rolled back. Reported-by: Gene Hackmann <ghackmann@google.com> Signed-off-by: Will Deacon <will.deacon@arm.com>