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2015-10-19arm64: Handle 4 level page table for swapperSuzuki K. Poulose
At the moment, we only support maximum of 3-level page table for swapper. With 48bit VA, 64K has only 3 levels and 4K uses section mapping. Add support for 4-level page table for swapper, needed by 16K pages. Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-19arm64: Move swapper pagetable definitionsSuzuki K. Poulose
Move the kernel pagetable (both swapper and idmap) definitions from the generic asm/page.h to a new file, asm/kernel-pgtable.h. This is mostly a cosmetic change, to clean up the asm/page.h to get rid of the arch specific details which are not needed by the generic code. Also renames the symbols to prevent conflicts. e.g, BLOCK_SHIFT => SWAPPER_BLOCK_SHIFT Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-16arm64: debug: Fix typo in debug-monitors.cYang Shi
Fix handers to handlers. Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-16arm64: AArch32 user space PC alignment exceptionMark Salyzyn
ARMv7 does not have a PC alignment exception. ARMv8 AArch32 user space however can produce a PC alignment exception. Add handler so that we do not dump an unexpected stack trace in the logs. Signed-off-by: Mark Salyzyn <salyzyn@android.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-14Merge tag 'efi-next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into core/efi Pull v4.4 EFI updates from Matt Fleming: - Make the EFI System Resource Table (ESRT) driver explicitly non-modular by ripping out the module_* code since Kconfig doesn't allow it to be built as a module anyway. (Paul Gortmaker) - Make the x86 efi=debug kernel parameter, which enables EFI debug code and output, generic and usable by arm64. (Leif Lindholm) - Add support to the x86 EFI boot stub for 64-bit Graphics Output Protocol frame buffer addresses. (Matt Fleming) - Detect when the UEFI v2.5 EFI_PROPERTIES_TABLE feature is enabled in the firmware and set an efi.flags bit so the kernel knows when it can apply more strict runtime mapping attributes - Ard Biesheuvel - Auto-load the efi-pstore module on EFI systems, just like we currently do for the efivars module. (Ben Hutchings) - Add "efi_fake_mem" kernel parameter which allows the system's EFI memory map to be updated with additional attributes for specific memory ranges. This is useful for testing the kernel code that handles the EFI_MEMORY_MORE_RELIABLE memmap bit even if your firmware doesn't include support. (Taku Izumi) Note: there is a semantic conflict between the following two commits: 8a53554e12e9 ("x86/efi: Fix multiple GOP device support") ae2ee627dc87 ("efifb: Add support for 64-bit frame buffer addresses") I fixed up the interaction in the merge commit, changing the type of current_fb_base from u32 to u64. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-14Merge branch 'x86/urgent' into core/efi, to pick up a pending EFI fixIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-13Merge branch 'linus' into irq/coreThomas Gleixner
Bring in upstream updates for patches which depend on them
2015-10-12arm64: add KASAN supportAndrey Ryabinin
This patch adds arch specific code for kernel address sanitizer (see Documentation/kasan.txt). 1/8 of kernel addresses reserved for shadow memory. There was no big enough hole for this, so virtual addresses for shadow were stolen from vmalloc area. At early boot stage the whole shadow region populated with just one physical page (kasan_zero_page). Later, this page reused as readonly zero shadow for some memory that KASan currently don't track (vmalloc). After mapping the physical memory, pages for shadow memory are allocated and mapped. Functions like memset/memmove/memcpy do a lot of memory accesses. If bad pointer passed to one of these function it is important to catch this. Compiler's instrumentation cannot do this since these functions are written in assembly. KASan replaces memory functions with manually instrumented variants. Original functions declared as weak symbols so strong definitions in mm/kasan/kasan.c could replace them. Original functions have aliases with '__' prefix in name, so we could call non-instrumented variant if needed. Some files built without kasan instrumentation (e.g. mm/slub.c). Original mem* function replaced (via #define) with prefixed variants to disable memory access checks for such files. Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-12arm64/efi: isolate EFI stub from the kernel properArd Biesheuvel
Since arm64 does not use a builtin decompressor, the EFI stub is built into the kernel proper. So far, this has been working fine, but actually, since the stub is in fact a PE/COFF relocatable binary that is executed at an unknown offset in the 1:1 mapping provided by the UEFI firmware, we should not be seamlessly sharing code with the kernel proper, which is a position dependent executable linked at a high virtual offset. So instead, separate the contents of libstub and its dependencies, by putting them into their own namespace by prefixing all of its symbols with __efistub. This way, we have tight control over what parts of the kernel proper are referenced by the stub. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-12efi/arm64: Clean up efi_get_fdt_params() interfaceLeif Lindholm
As we now have a common debug infrastructure between core and arm64 efi, drop the bit of the interface passing verbose output flags around. Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-10-12arm64: Use core efi=debug instead of uefi_debug command line parameterLeif Lindholm
Now that we have an efi=debug command line option in the core code, use this instead of the arm64-specific uefi_debug option. Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-10-12arm64: Fix missing #include in hw_breakpoint.cCatalin Marinas
A prior commit used to detect the hw breakpoint ABI behaviour based on the target state missed the asm/compat.h include and the build fails with !CONFIG_COMPAT. Fixes: 8f48c0629049 ("arm64: hw_breakpoint: use target state to determine ABI behaviour") Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-09arm64: cpufeatures: Check ICC_EL1_SRE.SRE before enabling ↵Marc Zyngier
ARM64_HAS_SYSREG_GIC_CPUIF As the firmware (or the hypervisor) may have disabled SRE access, check that SRE can actually be enabled before declaring that we do have that capability. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-09arm64: el2_setup: Make sure ICC_SRE_EL2.SRE sticks before using GICv3 sysregsMarc Zyngier
Contrary to what was originally expected, EL3 firmware can (for whatever reason) disable GICv3 system register access. In this case, the kernel explodes very early. Work around this by testing if the SRE bit sticks or not. If it doesn't, abort the GICv3 setup, and pray that the firmware has passed a DT that doesn't contain a GICv3 node. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-09arm64: fix a migrating irq bug when hotplug cpuYang Yingliang
When cpu is disabled, all irqs will be migratged to another cpu. In some cases, a new affinity is different, the old affinity need to be updated and if irq_set_affinity's return value is IRQ_SET_MASK_OK_DONE, the old affinity can not be updated. Fix it by using irq_do_set_affinity. And migrating interrupts is a core code matter, so use the generic function irq_migrate_all_off_this_cpu() to migrate interrupts in kernel/irq/migration.c. Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Cc: Hanjun Guo <hanjun.guo@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07arm64: perf: add Cortex-A57 supportMark Rutland
The Cortex-A57 PMU supports a few events outside of the required PMUv3 set that are rather useful. This patch adds the event map data for said events. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07arm64: perf: add Cortex-A53 supportMark Rutland
The Cortex-A53 PMU supports a few events outside of the required PMUv3 set that are rather useful. This patch adds the event map data for said events. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07arm64: perf: move to shared arm_pmu frameworkMark Rutland
Now that the arm_pmu framework has been factored out to drivers/perf we can make use of it for arm64, gaining support for heterogeneous PMUs and unifying the two codebases before they diverge further. The as yet unused PMU name for PMUv3 is changed to armv8_pmuv3, matching the style previously applied to the 32-bit PMUs. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07arm64: hw_breakpoint: use target state to determine ABI behaviourWill Deacon
The arm64 hw_breakpoint interface is slightly less flexible than its 32-bit counterpart, thanks to some changes in the architecture rendering unaligned watchpoint addresses obselete for AArch64. However, in a multi-arch environment (i.e. debugging a 32-bit target with a 64-bit GDB under a 64-bit kernel), we need to provide a feature compatible interface to GDB in order for debugging to function correctly. This patch adds a new helper, is_compat_bp, to our hw_breakpoint implementation which changes the interface behaviour based on the architecture of the debug target as opposed to the debugger itself. This allows debugged to function as expected for multi-arch configurations without relying on deprecated architectural behaviours when debugging native applications. Cc: Yao Qi <yao.qi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07arm64: mm: kill mm_cpumask usageWill Deacon
mm_cpumask isn't actually used for anything on arm64, so remove all the code trying to keep it up-to-date. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07arm64: mm: rewrite ASID allocator and MM context-switching codeWill Deacon
Our current switch_mm implementation suffers from a number of problems: (1) The ASID allocator relies on IPIs to synchronise the CPUs on a rollover event (2) Because of (1), we cannot allocate ASIDs with interrupts disabled and therefore make use of a TIF_SWITCH_MM flag to postpone the actual switch to finish_arch_post_lock_switch (3) We run context switch with a reserved (invalid) TTBR0 value, even though the ASID and pgd are updated atomically (4) We take a global spinlock (cpu_asid_lock) during context-switch (5) We use h/w broadcast TLB operations when they are not required (e.g. in flush_context) This patch addresses these problems by rewriting the ASID algorithm to match the bitmap-based arch/arm/ implementation more closely. This in turn allows us to remove much of the complications surrounding switch_mm, including the ugly thread flag. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07arm64: flush: use local TLB and I-cache invalidationWill Deacon
There are a number of places where a single CPU is running with a private page-table and we need to perform maintenance on the TLB and I-cache in order to ensure correctness, but do not require the operation to be broadcast to other CPUs. This patch adds local variants of tlb_flush_all and __flush_icache_all to support these use-cases and updates the callers respectively. __local_flush_icache_all also implies an isb, since it is intended to be used synchronously. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: David Daney <david.daney@cavium.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-06arm64: replace read_lock to rcu lock in call_break_hookYang Shi
BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 0, irqs_disabled(): 128, pid: 342, name: perf 1 lock held by perf/342: #0: (break_hook_lock){+.+...}, at: [<ffffffc0000851ac>] call_break_hook+0x34/0xd0 irq event stamp: 62224 hardirqs last enabled at (62223): [<ffffffc00010b7bc>] __call_rcu.constprop.59+0x104/0x270 hardirqs last disabled at (62224): [<ffffffc0000fbe20>] vprintk_emit+0x68/0x640 softirqs last enabled at (0): [<ffffffc000097928>] copy_process.part.8+0x428/0x17f8 softirqs last disabled at (0): [< (null)>] (null) CPU: 0 PID: 342 Comm: perf Not tainted 4.1.6-rt5 #4 Hardware name: linux,dummy-virt (DT) Call trace: [<ffffffc000089968>] dump_backtrace+0x0/0x128 [<ffffffc000089ab0>] show_stack+0x20/0x30 [<ffffffc0007030d0>] dump_stack+0x7c/0xa0 [<ffffffc0000c878c>] ___might_sleep+0x174/0x260 [<ffffffc000708ac8>] __rt_spin_lock+0x28/0x40 [<ffffffc000708db0>] rt_read_lock+0x60/0x80 [<ffffffc0000851a8>] call_break_hook+0x30/0xd0 [<ffffffc000085a70>] brk_handler+0x30/0x98 [<ffffffc000082248>] do_debug_exception+0x50/0xb8 Exception stack(0xffffffc00514fe30 to 0xffffffc00514ff50) fe20: 00000000 00000000 c1594680 0000007f fe40: ffffffff ffffffff 92063940 0000007f 0550dcd8 ffffffc0 00000000 00000000 fe60: 0514fe70 ffffffc0 000be1f8 ffffffc0 0514feb0 ffffffc0 0008948c ffffffc0 fe80: 00000004 00000000 0514fed0 ffffffc0 ffffffff ffffffff 9282a948 0000007f fea0: 00000000 00000000 9282b708 0000007f c1592820 0000007f 00083914 ffffffc0 fec0: 00000000 00000000 00000010 00000000 00000064 00000000 00000001 00000000 fee0: 005101e0 00000000 c1594680 0000007f c1594740 0000007f ffffffd8 ffffff80 ff00: 00000000 00000000 00000000 00000000 c1594770 0000007f c1594770 0000007f ff20: 00665e10 00000000 7f7f7f7f 7f7f7f7f 01010101 01010101 00000000 00000000 ff40: 928e4cc0 0000007f 91ff11e8 0000007f call_break_hook is called in atomic context (hard irq disabled), so replace the sleepable lock to rcu lock, replace relevant list operations to rcu version and call synchronize_rcu() in unregister_break_hook(). And, replace write lock to spinlock in {un}register_break_hook. Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-06arm64: Don't relocate non-existent initrdMark Rutland
When booting a kernel without an initrd, the kernel reports that it moves -1 bytes worth, having gone through the motions with initrd_start equal to initrd_end: Moving initrd from [4080000000-407fffffff] to [9fff49000-9fff48fff] Prevent this by bailing out early when the initrd size is zero (i.e. we have no initrd), avoiding the confusing message and other associated work. Fixes: 1570f0d7ab425c1e ("arm64: support initrd outside kernel linear map") Cc: Mark Salter <msalter@redhat.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-05arm64: convert patch_lock to raw lockYang Shi
When running kprobe test on arm64 rt kernel, it reports the below warning: root@qemu7:~# modprobe kprobe_example BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 0, irqs_disabled(): 128, pid: 484, name: modprobe CPU: 0 PID: 484 Comm: modprobe Not tainted 4.1.6-rt5 #2 Hardware name: linux,dummy-virt (DT) Call trace: [<ffffffc0000891b8>] dump_backtrace+0x0/0x128 [<ffffffc000089300>] show_stack+0x20/0x30 [<ffffffc00061dae8>] dump_stack+0x1c/0x28 [<ffffffc0000bbad0>] ___might_sleep+0x120/0x198 [<ffffffc0006223e8>] rt_spin_lock+0x28/0x40 [<ffffffc000622b30>] __aarch64_insn_write+0x28/0x78 [<ffffffc000622e48>] aarch64_insn_patch_text_nosync+0x18/0x48 [<ffffffc000622ee8>] aarch64_insn_patch_text_cb+0x70/0xa0 [<ffffffc000622f40>] aarch64_insn_patch_text_sync+0x28/0x48 [<ffffffc0006236e0>] arch_arm_kprobe+0x38/0x48 [<ffffffc00010e6f4>] arm_kprobe+0x34/0x50 [<ffffffc000110374>] register_kprobe+0x4cc/0x5b8 [<ffffffbffc002038>] kprobe_init+0x38/0x7c [kprobe_example] [<ffffffc000084240>] do_one_initcall+0x90/0x1b0 [<ffffffc00061c498>] do_init_module+0x6c/0x1cc [<ffffffc0000fd0c0>] load_module+0x17f8/0x1db0 [<ffffffc0000fd8cc>] SyS_finit_module+0xb4/0xc8 Convert patch_lock to raw loc kto avoid this issue. Although the problem is found on rt kernel, the fix should be applicable to mainline kernel too. Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-05arm64: debug: Fix typo in debug-monitors.cYang Shi
Fix comment typo: s/handers/handlers/ Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-04debugfs: Pass bool pointer to debugfs_create_bool()Viresh Kumar
Its a bit odd that debugfs_create_bool() takes 'u32 *' as an argument, when all it needs is a boolean pointer. It would be better to update this API to make it accept 'bool *' instead, as that will make it more consistent and often more convenient. Over that bool takes just a byte. That required updates to all user sites as well, in the same commit updating the API. regmap core was also using debugfs_{read|write}_file_bool(), directly and variable types were updated for that to be bool as well. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-03Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fixes from Ingo Molnar: "Two EFI fixes: one for x86, one for ARM, fixing a boot crash bug that can trigger under newer EFI firmware" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arm64/efi: Fix boot crash by not padding between EFI_MEMORY_RUNTIME regions x86/efi: Fix boot crash by mapping EFI memmap entries bottom-up at runtime, instead of top-down
2015-10-02drivers: firmware: psci: move power_state handling to generic codeLorenzo Pieralisi
Functions implemented on arm64 to check if a power_state parameter is valid and if the power_state implies context loss are not arm64 specific and should be moved to generic code so that they can be reused on arm systems too. This patch moves the functions handling the power_state parameter to generic PSCI firmware layer code. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Jisheng Zhang <jszhang@marvell.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com>
2015-10-02arm64: ftrace: fix function_graph tracer panicLi Bin
When function graph tracer is enabled, the following operation will trigger panic: mount -t debugfs nodev /sys/kernel echo next_tgid > /sys/kernel/tracing/set_ftrace_filter echo function_graph > /sys/kernel/tracing/current_tracer ls /proc/ ------------[ cut here ]------------ [ 198.501417] Unable to handle kernel paging request at virtual address cb88537fdc8ba316 [ 198.506126] pgd = ffffffc008f79000 [ 198.509363] [cb88537fdc8ba316] *pgd=00000000488c6003, *pud=00000000488c6003, *pmd=0000000000000000 [ 198.517726] Internal error: Oops: 94000005 [#1] SMP [ 198.518798] Modules linked in: [ 198.520582] CPU: 1 PID: 1388 Comm: ls Tainted: G [ 198.521800] Hardware name: linux,dummy-virt (DT) [ 198.522852] task: ffffffc0fa9e8000 ti: ffffffc0f9ab0000 task.ti: ffffffc0f9ab0000 [ 198.524306] PC is at next_tgid+0x30/0x100 [ 198.525205] LR is at return_to_handler+0x0/0x20 [ 198.526090] pc : [<ffffffc0002a1070>] lr : [<ffffffc0000907c0>] pstate: 60000145 [ 198.527392] sp : ffffffc0f9ab3d40 [ 198.528084] x29: ffffffc0f9ab3d40 x28: ffffffc0f9ab0000 [ 198.529406] x27: ffffffc000d6a000 x26: ffffffc000b786e8 [ 198.530659] x25: ffffffc0002a1900 x24: ffffffc0faf16c00 [ 198.531942] x23: ffffffc0f9ab3ea0 x22: 0000000000000002 [ 198.533202] x21: ffffffc000d85050 x20: 0000000000000002 [ 198.534446] x19: 0000000000000002 x18: 0000000000000000 [ 198.535719] x17: 000000000049fa08 x16: ffffffc000242efc [ 198.537030] x15: 0000007fa472b54c x14: ffffffffff000000 [ 198.538347] x13: ffffffc0fada84a0 x12: 0000000000000001 [ 198.539634] x11: ffffffc0f9ab3d70 x10: ffffffc0f9ab3d70 [ 198.540915] x9 : ffffffc0000907c0 x8 : ffffffc0f9ab3d40 [ 198.542215] x7 : 0000002e330f08f0 x6 : 0000000000000015 [ 198.543508] x5 : 0000000000000f08 x4 : ffffffc0f9835ec0 [ 198.544792] x3 : cb88537fdc8ba316 x2 : cb88537fdc8ba306 [ 198.546108] x1 : 0000000000000002 x0 : ffffffc000d85050 [ 198.547432] [ 198.547920] Process ls (pid: 1388, stack limit = 0xffffffc0f9ab0020) [ 198.549170] Stack: (0xffffffc0f9ab3d40 to 0xffffffc0f9ab4000) [ 198.582568] Call trace: [ 198.583313] [<ffffffc0002a1070>] next_tgid+0x30/0x100 [ 198.584359] [<ffffffc0000907bc>] ftrace_graph_caller+0x6c/0x70 [ 198.585503] [<ffffffc0000907bc>] ftrace_graph_caller+0x6c/0x70 [ 198.586574] [<ffffffc0000907bc>] ftrace_graph_caller+0x6c/0x70 [ 198.587660] [<ffffffc0000907bc>] ftrace_graph_caller+0x6c/0x70 [ 198.588896] Code: aa0003f5 2a0103f4 b4000102 91004043 (885f7c60) [ 198.591092] ---[ end trace 6a346f8f20949ac8 ]--- This is because when using function graph tracer, if the traced function return value is in multi regs ([x0-x7]), return_to_handler may corrupt them. So in return_to_handler, the parameter regs should be protected properly. Cc: <stable@vger.kernel.org> # 3.18+ Signed-off-by: Li Bin <huawei.libin@huawei.com> Acked-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-01arm64/efi: Fix boot crash by not padding between EFI_MEMORY_RUNTIME regionsArd Biesheuvel
The new Properties Table feature introduced in UEFIv2.5 may split memory regions that cover PE/COFF memory images into separate code and data regions. Since these regions only differ in the type (runtime code vs runtime data) and the permission bits, but not in the memory type attributes (UC/WC/WT/WB), the spec does not require them to be aligned to 64 KB. Since the relative offset of PE/COFF .text and .data segments cannot be changed on the fly, this means that we can no longer pad out those regions to be mappable using 64 KB pages. Unfortunately, there is no annotation in the UEFI memory map that identifies data regions that were split off from a code region, so we must apply this logic to all adjacent runtime regions whose attributes only differ in the permission bits. So instead of rounding each memory region to 64 KB alignment at both ends, only round down regions that are not directly preceded by another runtime region with the same type attributes. Since the UEFI spec does not mandate that the memory map be sorted, this means we also need to sort it first. Note that this change will result in all EFI_MEMORY_RUNTIME regions whose start addresses are not aligned to the OS page size to be mapped with executable permissions (i.e., on kernels compiled with 64 KB pages). However, since these mappings are only active during the time that UEFI Runtime Services are being invoked, the window for abuse is rather small. Tested-by: Mark Salter <msalter@redhat.com> Tested-by: Mark Rutland <mark.rutland@arm.com> [UEFI 2.4 only] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Reviewed-by: Mark Salter <msalter@redhat.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Cc: <stable@vger.kernel.org> # v4.0+ Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1443218539-7610-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-01clocksource: cosmetic: Drop OF 'dependency' from symbolsMarc Zyngier
Seeing the 'of' characters in a symbol that is being called from ACPI seems to freak out people. So let's do a bit of pointless renaming so that these folks do feel at home. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-01clocksource / arm_arch_timer: Convert to ACPI probingMarc Zyngier
It is now absolutely trivial to convert the arch timer driver to use ACPI probing, just like its DT counterpart. Let's enjoy another crapectomy. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-01irqchip / GIC: Convert the GIC driver to ACPI probingMarc Zyngier
Now that we have a basic infrastructure to register irqchips and call them on discovery of a matching entry in MADT, convert the GIC driver to this new probing method. It ends up being a code deletion party, which is a rather good thing. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-29irqchip/gicv3: Workaround for Cavium ThunderX erratum 23154Robert Richter
This patch implements Cavium ThunderX erratum 23154. The gicv3 of ThunderX requires a modified version for reading the IAR status to ensure data synchronization. Since this is in the fast-path and called with each interrupt, runtime patching is used using jump label patching for smallest overhead (no-op). This is the same technique as used for tracepoints. Signed-off-by: Robert Richter <rrichter@cavium.com> Reviewed-by: Marc Zygnier <marc.zyngier@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Tirumalesh Chalamarla <tchalamarla@cavium.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Jason Cooper <jason@lakedaemon.net> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/1442869119-1814-3-git-send-email-rric@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-17arm64: errata: add module build workaround for erratum #843419Will Deacon
Cortex-A53 processors <= r0p4 are affected by erratum #843419 which can lead to a memory access using an incorrect address in certain sequences headed by an ADRP instruction. There is a linker fix to generate veneers for ADRP instructions, but this doesn't work for kernel modules which are built as unlinked ELF objects. This patch adds a new config option for the erratum which, when enabled, builds kernel modules with the mcmodel=large flag. This uses absolute addressing for all kernel symbols, thereby removing the use of ADRP as a PC-relative form of addressing. The ADRP relocs are removed from the module loader so that we fail to load any potentially affected modules. Cc: <stable@vger.kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-09-17arm64: compat: fix vfp save/restore across signal handlers in big-endianWill Deacon
When saving/restoring the VFP registers from a compat (AArch32) signal frame, we rely on the compat registers forming a prefix of the native register file and therefore make use of copy_{to,from}_user to transfer between the native fpsimd_state and the compat_vfp_sigframe. Unfortunately, this doesn't work so well in a big-endian environment. Our fpsimd save/restore code operates directly on 128-bit quantities (Q registers) whereas the compat_vfp_sigframe represents the registers as an array of 64-bit (D) registers. The architecture packs the compat D registers into the Q registers, with the least significant bytes holding the lower register. Consequently, we need to swap the 64-bit halves when converting between these two representations on a big-endian machine. This patch replaces the __copy_{to,from}_user invocations in our compat VFP signal handling code with explicit __put_user loops that operate on 64-bit values and swap them accordingly. Cc: <stable@vger.kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-09-17arm64: cpu hotplug: ensure we mask out CPU_TASKS_FROZEN in notifiersWill Deacon
We have a couple of CPU hotplug notifiers for resetting the CPU debug state to a sane value when a CPU comes online. This patch ensures that we mask out CPU_TASKS_FROZEN so that we don't miss any online events occuring due to suspend/resume. Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-09-15arm64: head.S: initialise mdcr_el2 in el2_setupWill Deacon
When entering the kernel at EL2, we fail to initialise the MDCR_EL2 register which controls debug access and PMU capabilities at EL1. This patch ensures that the register is initialised so that all traps are disabled and all the PMU counters are available to the host. When a guest is scheduled, KVM takes care to configure trapping appropriately. Cc: <stable@vger.kernel.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-09-14arm64, acpi/apei: Implement arch_apei_get_mem_attributes()Jonathan (Zhixiong) Zhang
Table 8 of UEFI 2.5 section 2.3.6.1 defines mappings from EFI memory types to MAIR attribute encodings for arm64. If the physical address has memory attributes defined by EFI memmap as EFI_MEMORY_[UC|WC|WT], return approprate page protection type according to the UEFI spec. Otherwise, return PAGE_KERNEL. Signed-off-by: Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> [ Small stylistic tweaks. ] Reviewed-by: Matt Fleming <matt.fleming@intel.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/1441372302-23242-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-10Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull more kvm updates from Paolo Bonzini: "ARM: - Full debug support for arm64 - Active state switching for timer interrupts - Lazy FP/SIMD save/restore for arm64 - Generic ARMv8 target PPC: - Book3S: A few bug fixes - Book3S: Allow micro-threading on POWER8 x86: - Compiler warnings Generic: - Adaptive polling for guest halt" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (49 commits) kvm: irqchip: fix memory leak kvm: move new trace event outside #ifdef CONFIG_KVM_ASYNC_PF KVM: trace kvm_halt_poll_ns grow/shrink KVM: dynamic halt-polling KVM: make halt_poll_ns per-vCPU Silence compiler warning in arch/x86/kvm/emulate.c kvm: compile process_smi_save_seg_64() only for x86_64 KVM: x86: avoid uninitialized variable warning KVM: PPC: Book3S: Fix typo in top comment about locking KVM: PPC: Book3S: Fix size of the PSPB register KVM: PPC: Book3S HV: Exit on H_DOORBELL if HOST_IPI is set KVM: PPC: Book3S HV: Fix race in starting secondary threads KVM: PPC: Book3S: correct width in XER handling KVM: PPC: Book3S HV: Fix preempted vcore stolen time calculation KVM: PPC: Book3S HV: Fix preempted vcore list locking KVM: PPC: Book3S HV: Implement H_CLEAR_REF and H_CLEAR_MOD KVM: PPC: Book3S HV: Fix bug in dirty page tracking KVM: PPC: Book3S HV: Fix race in reading change bit when removing HPTE KVM: PPC: Book3S HV: Implement dynamic micro-threading on POWER8 KVM: PPC: Book3S HV: Make use of unused threads when running guests ...
2015-09-08arm64: support initrd outside kernel linear mapMark Salter
The use of mem= could leave part or all of the initrd outside of the kernel linear map. This will lead to an error when unpacking the initrd and a probable failure to boot. This patch catches that situation and relocates the initrd to be fully within the linear map. Signed-off-by: Mark Salter <msalter@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: - Support for new architectural features introduced in ARMv8.1: * Privileged Access Never (PAN) to catch user pointer dereferences in the kernel * Large System Extension (LSE) for building scalable atomics and locks (depends on locking/arch-atomic from tip, which is included here) * Hardware Dirty Bit Management (DBM) for updating clean PTEs automatically - Move our PSCI implementation out into drivers/firmware/, where it can be shared with arch/arm/. RMK has also pulled this component branch and has additional patches moving arch/arm/ over. MAINTAINERS is updated accordingly. - Better BUG implementation based on the BRK instruction for trapping - Leaf TLB invalidation for unmapping user pages - Support for PROBE_ONLY PCI configurations - Various cleanups and non-critical fixes, including: * Always flush FP/SIMD state over exec() * Restrict memblock additions based on range of linear mapping * Ensure *(LIST_POISON) generates a fatal fault * Context-tracking syscall return no longer corrupts return value when not forced on. * Alternatives patching synchronisation/stability improvements * Signed sub-word cmpxchg compare fix (tickled by HAVE_CMPXCHG_LOCAL) * Force SMP=y * Hide direct DCC access from userspace * Fix EFI stub memory allocation when DRAM starts at 0x0 * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) arm64: flush FP/SIMD state correctly after execve() arm64: makefile: fix perf_callchain.o kconfig dependency arm64: set MAX_MEMBLOCK_ADDR according to linear region size of/fdt: make memblock maximum physical address arch configurable arm64: Fix source code file path in comments arm64: entry: always restore x0 from the stack on syscall return arm64: mdscr_el1: avoid exposing DCC to userspace arm64: kconfig: Move LIST_POISON to a safe value arm64: Add __exception_irq_entry definition for function graph arm64: mm: ensure patched kernel text is fetched from PoU arm64: alternatives: ensure secondary CPUs execute ISB after patching arm64: make ll/sc __cmpxchg_case_##name asm consistent arm64: dma-mapping: Simplify pgprot handling arm64: restore cpu suspend/resume functionality ARM64: PCI: do not enable resources on PROBE_ONLY systems arm64: cmpxchg: truncate sub-word signed types before comparison arm64: alternative: put secondary CPUs into polling loop during patch arm64/Documentation: clarify wording regarding memory below the Image arm64: lse: fix lse cmpxchg code indentation arm64: remove redundant object file list ...
2015-09-03Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds
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 ...
2015-09-03Merge branch 'locking-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking and atomic updates from Ingo Molnar: "Main changes in this cycle are: - Extend atomic primitives with coherent logic op primitives (atomic_{or,and,xor}()) and deprecate the old partial APIs (atomic_{set,clear}_mask()) The old ops were incoherent with incompatible signatures across architectures and with incomplete support. Now every architecture supports the primitives consistently (by Peter Zijlstra) - Generic support for 'relaxed atomics': - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return() - atomic_read_acquire() - atomic_set_release() This came out of porting qwrlock code to arm64 (by Will Deacon) - Clean up the fragile static_key APIs that were causing repeat bugs, by introducing a new one: DEFINE_STATIC_KEY_TRUE(name); DEFINE_STATIC_KEY_FALSE(name); which define a key of different types with an initial true/false value. Then allow: static_branch_likely() static_branch_unlikely() to take a key of either type and emit the right instruction for the case. To be able to know the 'type' of the static key we encode it in the jump entry (by Peter Zijlstra) - Static key self-tests (by Jason Baron) - qrwlock optimizations (by Waiman Long) - small futex enhancements (by Davidlohr Bueso) - ... and misc other changes" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits) jump_label/x86: Work around asm build bug on older/backported GCCs locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics locking/qrwlock: Implement queue_write_unlock() using smp_store_release() locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t' locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic locking/static_keys: Make verify_keys() static jump label, locking/static_keys: Update docs locking/static_keys: Provide a selftest jump_label: Provide a self-test s390/uaccess, locking/static_keys: employ static_branch_likely() x86, tsc, locking/static_keys: Employ static_branch_likely() locking/static_keys: Add selftest locking/static_keys: Add a new static_key interface locking/static_keys: Rework update logic locking/static_keys: Add static_key_{en,dis}able() helpers ...
2015-08-31Merge tag 'clk-for-linus-4.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk updates from Michael Turquette: "The clk framework changes for 4.3 are mostly updates to existing drivers and the addition of new clock drivers. Stephen Boyd has also done a lot of subsystem-wide driver clean-ups (thanks!). There are also fixes to the framework core and changes to better split clock provider drivers from clock consumer drivers" * tag 'clk-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (227 commits) clk: s5pv210: add missing call to samsung_clk_of_add_provider() clk: pistachio: correct critical clock list clk: pistachio: Fix PLL rate calculation in integer mode clk: pistachio: Fix override of clk-pll settings from boot loader clk: pistachio: Fix 32bit integer overflows clk: tegra: Fix some static checker problems clk: qcom: Fix MSM8916 prng clock enable bit clk: Add missing header for 'bool' definition to clk-conf.h drivers/clk: appropriate __init annotation for const data clk: rockchip: register pll mux before pll itself clk: add bindings for the Ux500 clocks clk/ARM: move Ux500 PRCC bases to the device tree clk: remove duplicated code with __clk_set_parent_after clk: Convert __clk_get_name(hw->clk) to clk_hw_get_name(hw) clk: Constify clk_hw argument to provider APIs clk: Hi6220: add stub clock driver dt-bindings: clk: Hi6220: Document stub clock driver dt-bindings: arm: Hi6220: add doc for SRAM controller clk: atlas7: fix pll missed divide NR in fraction mode clk: atlas7: fix bit field and its root clk for coresight_tpiu ...
2015-08-27arm64: flush FP/SIMD state correctly after execve()Ard Biesheuvel
When a task calls execve(), its FP/SIMD state is flushed so that none of the original program state is observeable by the incoming program. However, since this flushing consists of setting the in-memory copy of the FP/SIMD state to all zeroes, the CPU field is set to CPU 0 as well, which indicates to the lazy FP/SIMD preserve/restore code that the FP/SIMD state does not need to be reread from memory if the task is scheduled again on CPU 0 without any other tasks having entered userland (or used the FP/SIMD in kernel mode) on the same CPU in the mean time. If this happens, the FP/SIMD state of the old program will still be present in the registers when the new program starts. So set the CPU field to the invalid value of NR_CPUS when performing the flush, by calling fpsimd_flush_task_state(). Cc: <stable@vger.kernel.org> Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com> Reported-by: Janet Liu <janet.liu@spreadtrum.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-24arm64: makefile: fix perf_callchain.o kconfig dependencyWill Deacon
Commit 4b3dc9679cf7 ("arm64: force CONFIG_SMP=y and remove redundant #ifdefs") incorrectly resolved a conflict on arch/arm64/kernel/Makefile which resulted in a partial revert of 52da443ec4d0 ("arm64: perf: factor out callchain code"), leading to perf_callchain.o depending on CONFIG_HW_PERF_EVENTS instead of CONFIG_PERF_EVENTS. This patch restores the kconfig dependency for perf_callchain.o. Reported-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-22Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into ↵Paolo Bonzini
kvm-queue Patch queue for ppc - 2015-08-22 Highlights for KVM PPC this time around: - Book3S: A few bug fixes - Book3S: Allow micro-threading on POWER8
2015-08-21arm64: entry: always restore x0 from the stack on syscall returnWill Deacon
We have a micro-optimisation on the fast syscall return path where we take care to keep x0 live with the return value from the syscall so that we can avoid restoring it from the stack. The benefit of doing this is fairly suspect, since we will be restoring x1 from the stack anyway (which lives adjacent in the pt_regs structure) and the only additional cost is saving x0 back to pt_regs after the syscall handler, which could be seen as a poor man's prefetch. More importantly, this causes issues with the context tracking code. The ct_user_enter macro ends up branching into C code, which is free to use x0 as a scratch register and consequently leads to us returning junk back to userspace as the syscall return value. Rather than special case the context-tracking code, this patch removes the questionable optimisation entirely. Cc: <stable@vger.kernel.org> Cc: Larry Bassel <larry.bassel@linaro.org> Cc: Kevin Hilman <khilman@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>