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2022-01-22proc: remove PDE_DATA() completelyMuchun Song
Remove PDE_DATA() completely and replace it with pde_data(). [akpm@linux-foundation.org: fix naming clash in drivers/nubus/proc.c] [akpm@linux-foundation.org: now fix it properly] Link: https://lkml.kernel.org/r/20211124081956.87711-2-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Alexey Gladkov <gladkov.alexey@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-17Merge branch 'signal-for-v5.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc/<pid>/stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...
2022-01-12Merge tag 'perf_core_for_v5.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Borislav Petkov: "Cleanup of the perf/kvm interaction." * tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Drop guest callback (un)register stubs KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c KVM: arm64: Hide kvm_arm_pmu_available behind CONFIG_HW_PERF_EVENTS=y KVM: arm64: Convert to the generic perf callbacks KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c KVM: Move x86's perf guest info callbacks to generic KVM KVM: x86: More precisely identify NMI from guest when handling PMI KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu variable perf/core: Use static_call to optimize perf_guest_info_callbacks perf: Force architectures to opt-in to guest callbacks perf: Add wrappers for invoking guest callbacks perf/core: Rework guest callbacks to prepare for static_call support perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscv perf: Stop pretending that perf can handle multiple guest callbacks KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest KVM: x86: Register perf callbacks after calling vendor's hardware_setup() perf: Protect perf_guest_cbs with RCU
2022-01-11Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: - amba bus irq rework - add kfence support - support for Cortex M33 and M55 CPUs - kbuild updates for decompressor - let core code manage thread_info::cpu - avoid unpredictable NOP encoding in decompressor - reduce information printed in calltraces * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: reduce the information printed in call traces ARM: 9168/1: Add support for Cortex-M55 processor ARM: 9167/1: Add support for Cortex-M33 processor ARM: 9166/1: Support KFENCE for ARM ARM: 9165/1: mm: Provide is_write_fault() ARM: 9164/1: mm: Provide set_memory_valid() ARM: 9163/1: amba: Move of_amba_device_decode_irq() into amba_probe() ARM: 9162/1: amba: Kill sysfs attribute file of irq ARM: 9161/1: mm: mark private VM_FAULT_X defines as vm_fault_t ARM: 9159/1: decompressor: Avoid UNPREDICTABLE NOP encoding ARM: 9158/1: leave it to core code to manage thread_info::cpu ARM: 9154/1: decompressor: do not copy source files while building
2022-01-10Merge tag 'core_entry_for_v5.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull thread_info flag accessor helper updates from Borislav Petkov: "Add a set of thread_info.flags accessors which snapshot it before accesing it in order to prevent any potential data races, and convert all users to those new accessors" * tag 'core_entry_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: powerpc: Snapshot thread flags powerpc: Avoid discarding flags in system_call_exception() openrisc: Snapshot thread flags microblaze: Snapshot thread flags arm64: Snapshot thread flags ARM: Snapshot thread flags alpha: Snapshot thread flags sched: Snapshot thread flags entry: Snapshot thread flags x86: Snapshot thread flags thread_info: Add helpers to snapshot thread flags
2021-12-17ARM: 9169/1: entry: fix Thumb2 bug in iWMMXt exception handlingArd Biesheuvel
The Thumb2 version of the FP exception handling entry code treats the register holding the CP number (R8) differently, resulting in the iWMMXT CP number check to be incorrect. Fix this by unifying the ARM and Thumb2 code paths, and switch the order of the additions of the TI_USED_CP offset and the shifted CP index. Cc: <stable@vger.kernel.org> Fixes: b86040a59feb ("Thumb-2: Implementation of the unified start-up and exceptions code") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-17ARM: 9160/1: NOMMU: Reload __secondary_data after PROCINFO_INITFUNCVladimir Murzin
__secondary_data used to reside in r7 around call to PROCINFO_INITFUNC. After commit 95731b8ee63e ("ARM: 9059/1: cache-v7: get rid of mini-stack") r7 is used as a scratch register, so we have to reload __secondary_data before we setup the stack pointer. Fixes: 95731b8ee63e ("ARM: 9059/1: cache-v7: get rid of mini-stack") Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-17ARM: reduce the information printed in call tracesRussell King
A while back, Linus complained about the numeric values printed by the ARM backtracing code. Printing these values does not make sense if one does not have access to the kernel ELF image (as is normally the case when helping a third party on a mailing list), but if one does, they can be very useful to find the code, rather than searching for the function name, and then doing hex math to work out where the backtrace entry is referring to. Provide an option to control whether this information is included, which will only be visible if EXPERT is enabled. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-12-17ARM: 9158/1: leave it to core code to manage thread_info::cpuArd Biesheuvel
Since commit bcf9033e5449 ("sched: move CPU field back into thread_info if THREAD_INFO_IN_TASK=y"), the CPU field in thread_info went back to being managed by the core code, so we no longer have to keep it in sync in arch code. While at it, mark THREAD_INFO_IN_TASK as done for ARM in the documentation. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-13exit: Add and use make_task_dead.Eric W. Biederman
There are two big uses of do_exit. The first is it's design use to be the guts of the exit(2) system call. The second use is to terminate a task after something catastrophic has happened like a NULL pointer in kernel code. Add a function make_task_dead that is initialy exactly the same as do_exit to cover the cases where do_exit is called to handle catastrophic failure. In time this can probably be reduced to just a light wrapper around do_task_dead. For now keep it exactly the same so that there will be no behavioral differences introducing this new concept. Replace all of the uses of do_exit that use it for catastraphic task cleanup with make_task_dead to make it clear what the code is doing. As part of this rename rewind_stack_do_exit rewind_stack_and_make_dead. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-12-06ARM: v7m: enable support for IRQ stacksArd Biesheuvel
Enable support for IRQ stacks on !MMU, and add the code to the IRQ entry path to switch to the IRQ stack if not running from it already. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06ARM: implement THREAD_INFO_IN_TASK for uniprocessor systemsArd Biesheuvel
On UP systems, only a single task can be 'current' at the same time, which means we can use a global variable to track it. This means we can also enable THREAD_INFO_IN_TASK for those systems, as in that case, thread_info is accessed via current rather than the other way around, removing the need to store thread_info at the base of the task stack. This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP systems as well. To partially mitigate the performance overhead of this arrangement, use a ADD/ADD/LDR sequence with the appropriate PC-relative group relocations to load the value of current when needed. This means that accessing current will still only require a single load as before, avoiding the need for a literal to carry the address of the global variable in each function. However, accessing thread_info will now require this load as well. Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06ARM: smp: defer TPIDRURO update for SMP v6 configurations tooArd Biesheuvel
Defer TPIDURO updates for user space until exit also for CPU_V6+SMP configurations so that we can decide at runtime whether to use it to carry the current pointer, provided that we are running on a CPU that actually implements this register. This is needed for THREAD_INFO_IN_TASK support for UP systems, which requires that all SMP capable systems use the TPIDRURO based access to 'current' as the only remaining alternative will be a global variable which only works on UP. Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06ARM: percpu: add SMP_ON_UP supportArd Biesheuvel
Permit the use of the TPIDRPRW system register for carrying the per-CPU offset in generic SMP configurations that also target non-SMP capable ARMv6 cores. This uses the SMP_ON_UP code patching framework to turn all TPIDRPRW accesses into reads/writes of entry #0 in the __per_cpu_offset array. While at it, switch over some existing direct TPIDRPRW accesses in asm code to invocations of a new helper that is patched in the same way when necessary. Note that CPU_V6+SMP without SMP_ON_UP results in a kernel that does not boot on v6 CPUs without SMP extensions, so add this dependency to Kconfig as well. Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06ARM: assembler: add optimized ldr/str macros to load variables from memoryArd Biesheuvel
We will be adding variable loads to various hot paths, so it makes sense to add a helper macro that can load variables from asm code without the use of literal pool entries. On v7 or later, we can simply use MOVW/MOVT pairs, but on earlier cores, this requires a bit of hackery to emit a instruction sequence that implements this using a sequence of ADD/LDR instructions. Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06ARM: module: implement support for PC-relative group relocationsArd Biesheuvel
Add support for the R_ARM_ALU_PC_Gn_NC and R_ARM_LDR_PC_G2 group relocations [0] so we can use them in modules. These will be used to load the current task pointer from a global variable without having to rely on a literal pool entry to carry the address of this variable, which may have a significant negative impact on cache utilization for variables that are used often and in many different places, as each occurrence will result in a literal pool entry and therefore a line in the D-cache. [0] 'ELF for the ARM architecture' https://github.com/ARM-software/abi-aa/releases Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06ARM: entry: preserve thread_info pointer in switch_toArd Biesheuvel
Tweak the UP stack protector handling code so that the thread info pointer is preserved in R7 until set_current is called. This is needed for a subsequent patch that implements THREAD_INFO_IN_TASK and set_current for UP as well. This also means we will prefer the per-task protector on UP systems that implement the thread ID registers, so tweak the preprocessor conditionals to reflect this. Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06irqchip: nvic: Use GENERIC_IRQ_MULTI_HANDLERVladimir Murzin
Rather then restructuring the ARMv7M entrly logic per TODO, just move NVIC to GENERIC_IRQ_MULTI_HANDLER. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-06ARM: remove old-style irq entryArnd Bergmann
The last user of arch_irq_handler_default is gone now, so the entry-macro-multi.S file and all references to mach/entry-macro.S can be removed, as well as the asm_do_IRQ() entrypoint into the interrupt handling routines implemented in C. Note: The ARMv7-M entry still uses its own top-level IRQ entry, calling nvic_handle_irq() from assembly. This could be changed to go through generic_handle_arch_irq() as well, but it's unclear to me if there are any benefits. Signed-off-by: Arnd Bergmann <arnd@arndb.de> [ardb: keep irq_handler macro as it carries all the IRQ stack handling] Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2021-12-06ARM: iop32x: use GENERIC_IRQ_MULTI_HANDLERArnd Bergmann
iop32x uses the entry-macro.S file for both the IRQ entry and for hooking into the arch_ret_to_user code path. This is done because the cp6 registers have to be enabled before accessing any of the interrupt controller registers but have to be disabled when running in user space. There is also a lazy-enable logic in cp6.c, but during a hardirq, we know it has to be enabled. Both the cp6-enable code and the code to read the IRQ status can be lifted into the normal generic_handle_arch_irq() path, but the cp6-disable code has to remain in the user return code. As nothing other than iop32x uses this hook, just open-code it there with an ifdef for the platform that can eventually be removed when iop32x has reached the end of its life. The cp6-enable path in the IRQ entry has an extra cp_wait barrier that the trap version does not have, but it is harmless to do it in both cases to simplify the logic here at the cost of a few extra cycles for the trap. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: implement support for vmap'ed stacksArd Biesheuvel
Wire up the generic support for managing task stack allocations via vmalloc, and implement the entry code that detects whether we faulted because of a stack overrun (or future stack overrun caused by pushing the pt_regs array) While this adds a fair amount of tricky entry asm code, it should be noted that it only adds a TST + branch to the svc_entry path. The code implementing the non-trivial handling of the overflow stack is emitted out-of-line into the .text section. Since on ARM, we rely on do_translation_fault() to keep PMD level page table entries that cover the vmalloc region up to date, we need to ensure that we don't hit such a stale PMD entry when accessing the stack. So we do a dummy read from the new stack while still running from the old one on the context switch path, and bump the vmalloc_seq counter when PMD level entries in the vmalloc range are modified, so that the MM switch fetches the latest version of the entries. Note that we need to increase the per-mode stack by 1 word, to gain some space to stash a GPR until we know it is safe to touch the stack. However, due to the cacheline alignment of the struct, this does not actually increase the memory footprint of the struct stack array at all. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: entry: rework stack realignment code in svc_entryArd Biesheuvel
The original Thumb-2 enablement patches updated the stack realignment code in svc_entry to work around the lack of a STMIB instruction in Thumb-2, by subtracting 4 from the frame size, inverting the sense of the misaligment check, and changing to a STMIA instruction and a final stack push of a 4 byte quantity that results in the stack becoming aligned at the end of the sequence. It also pushes and pops R0 to the stack in order to have a temp register that Thumb-2 allows in general purpose ALU instructions, as TST using SP is not permitted. Both are a bit problematic for vmap'ed stacks, as using the stack is only permitted after we decide that we did not overflow the stack, or have already switched to the overflow stack. As for the alignment check: the current approach creates a corner case where, if the initial SUB of SP ends up right at the start of the stack, we will end up subtracting another 8 bytes and overflowing it. This means we would need to add the overflow check *after* the SUB that deliberately misaligns the stack. However, this would require us to keep local state (i.e., whether we performed the subtract or not) across the overflow check, but without any GPRs or stack available. So let's switch to an approach where we don't use the stack, and where the alignment check of the stack pointer occurs in the usual way, as this is guaranteed not to result in overflow. This means we will be able to do the overflow check first. While at it, switch to R1 so the mode stack pointer in R0 remains accessible. Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: switch_to: clean up Thumb2 code pathArd Biesheuvel
The load-multiple instruction that essentially performs the switch_to operation in ARM mode, by loading all callee save registers as well the stack pointer and the program counter, is split into 3 separate loads for Thumb-2, with the IP register used as a temporary to capture the value of R4 before it gets overwritten. We can clean this up a bit, by sticking with a single LDMIA instruction, but one that pops SP and PC into IP and LR, respectively, and by using ordinary move register and branch instructions to get those values into SP and PC. This also allows us to move the set_current call closer to the assignment of SP, reducing the window where those are mutually out of sync. This is especially relevant for CONFIG_VMAP_STACK, which is being introduced in a subsequent patch, where we need to issue a load that might fault from the new stack while running from the old one, to ensure that stale PMD entries in the VMALLOC space are synced up. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: unwind: disregard unwind info before stack frame is set upArd Biesheuvel
When unwinding the stack from a stack overflow, we are likely to start from a stack push instruction, given that this is the most common way to grow the stack for compiler emitted code. This push instruction rarely appears anywhere else than at offset 0x0 of the function, and if it doesn't, the compiler tends to split up the unwind annotations, given that the stack frame layout is apparently not the same throughout the function. This means that, in the general case, if the frame's PC points at the first instruction covered by a certain unwind entry, there is no way the stack frame that the unwind entry describes could have been created yet, and so we are still on the stack frame of the caller in that case. So treat this as a special case, and return with the new PC taken from the frame's LR, without applying the unwind transformations to the virtual register set. This permits us to unwind the call stack on stack overflow when the overflow was caused by a stack push on function entry. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: run softirqs on the per-CPU IRQ stackArd Biesheuvel
Now that we have enabled IRQ stacks, any softIRQs that are handled over the back of a hard IRQ will run from the IRQ stack as well. However, any synchronous softirq processing that happens when re-enabling softIRQs from task context will still execute on that task's stack. Since any call to local_bh_enable() at any level in the task's call stack may trigger a softIRQ processing run, which could potentially cause a task stack overflow if the combined stack footprints exceed the stack's size, let's run these synchronous invocations of do_softirq() on the IRQ stack as well. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: implement IRQ stacksArd Biesheuvel
Now that we no longer rely on the stack pointer to access the current task struct or thread info, we can implement support for IRQ stacks cleanly as well. Define a per-CPU IRQ stack and switch to this stack when taking an IRQ, provided that we were not already using that stack in the interrupted context. This is never the case for IRQs taken from user space, but ones taken while running in the kernel could fire while one taken from user space has not completed yet. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Keith Packard <keithpac@amazon.com> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: unwind: dump exception stack from calling frameArd Biesheuvel
The existing code that dumps the contents of the pt_regs structure passed to __entry routines does so while unwinding the callee frame, and dereferences the stack pointer as a struct pt_regs*. This will no longer work when we enable support for IRQ or overflow stacks, because the struct pt_regs may live on the task stack, while we are executing from another stack. The unwinder has access to this information, but only while unwinding the calling frame. So let's combine the exception stack dumping code with the handling of the calling frame as well. By printing it before dumping the caller/callee addresses, the output order is preserved. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: export dump_mem() to other objectsArd Biesheuvel
The unwind info based stack unwinder will make its own call to dump_mem() to dump the exception stack, so give it external linkage. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: unwind: support unwinding across multiple stacksArd Biesheuvel
Implement support in the unwinder for dealing with multiple stacks. This will be needed once we add support for IRQ stacks, or for the overflow stack used by the vmap'ed stacks code. This involves tracking the unwind opcodes that either update the virtual stack pointer from another virtual register, or perform an explicit subtract on the virtual stack pointer, and updating the low and high bounds that we use to sanitize the stack pointer accordingly. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-03ARM: remove some dead codeArd Biesheuvel
This code appears to be no longer used so let's get rid of it. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
2021-12-01ARM: Snapshot thread flagsMark Rutland
Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Link: https://lore.kernel.org/r/20211129130653.2037928-6-mark.rutland@arm.com
2021-11-17perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscvSean Christopherson
Drop "support" for guest callbacks from architectures that don't implement the guest callbacks. Future patches will convert the callbacks to static_call; rather than churn a bunch of arch code (that was presumably copy+pasted from x86), remove it wholesale as it's useless and at best wasting cycles. A future patch will also add a Kconfig to force architcture to opt into the callbacks to make it more difficult for uses "support" to sneak in in the future. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20211111020738.2512932-6-seanjc@google.com
2021-11-17perf: Protect perf_guest_cbs with RCUSean Christopherson
Protect perf_guest_cbs with RCU to fix multiple possible errors. Luckily, all paths that read perf_guest_cbs already require RCU protection, e.g. to protect the callback chains, so only the direct perf_guest_cbs touchpoints need to be modified. Bug #1 is a simple lack of WRITE_ONCE/READ_ONCE behavior to ensure perf_guest_cbs isn't reloaded between a !NULL check and a dereference. Fixed via the READ_ONCE() in rcu_dereference(). Bug #2 is that on weakly-ordered architectures, updates to the callbacks themselves are not guaranteed to be visible before the pointer is made visible to readers. Fixed by the smp_store_release() in rcu_assign_pointer() when the new pointer is non-NULL. Bug #3 is that, because the callbacks are global, it's possible for readers to run in parallel with an unregisters, and thus a module implementing the callbacks can be unloaded while readers are in flight, resulting in a use-after-free. Fixed by a synchronize_rcu() call when unregistering callbacks. Bug #1 escaped notice because it's extremely unlikely a compiler will reload perf_guest_cbs in this sequence. perf_guest_cbs does get reloaded for future derefs, e.g. for ->is_user_mode(), but the ->is_in_guest() guard all but guarantees the consumer will win the race, e.g. to nullify perf_guest_cbs, KVM has to completely exit the guest and teardown down all VMs before KVM start its module unload / unregister sequence. This also makes it all but impossible to encounter bug #3. Bug #2 has not been a problem because all architectures that register callbacks are strongly ordered and/or have a static set of callbacks. But with help, unloading kvm_intel can trigger bug #1 e.g. wrapping perf_guest_cbs with READ_ONCE in perf_misc_flags() while spamming kvm_intel module load/unload leads to: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 6 PID: 1825 Comm: stress Not tainted 5.14.0-rc2+ #459 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:perf_misc_flags+0x1c/0x70 Call Trace: perf_prepare_sample+0x53/0x6b0 perf_event_output_forward+0x67/0x160 __perf_event_overflow+0x52/0xf0 handle_pmi_common+0x207/0x300 intel_pmu_handle_irq+0xcf/0x410 perf_event_nmi_handler+0x28/0x50 nmi_handle+0xc7/0x260 default_do_nmi+0x6b/0x170 exc_nmi+0x103/0x130 asm_exc_nmi+0x76/0xbf Fixes: 39447b386c84 ("perf: Enhance perf to allow for guest statistic collection from host") Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20211111020738.2512932-2-seanjc@google.com
2021-11-02Merge tag 'devicetree-for-5.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull devicetree updates from Rob Herring: - Convert /reserved-memory bindings to schemas - Convert a bunch of NFC bindings to schemas - Convert bindings to schema: Xilinx USB, Freescale DDR controller, Arm CCI-400, UBlox Neo-6M, 1-Wire GPIO, MSI controller, ASpeed LPC, OMAP and Inside-Secure HWRNG, register-bit-led, OV5640, Silead GSL1680, Elan ekth3000, Marvell bluetooth, TI wlcore, TI bluetooth, ESP ESP8089, tlm,trusted-foundations, Microchip cap11xx, Ralink SoCs and boards, and TI sysc - New binding schemas for: msi-ranges, Aspeed UART routing controller, palmbus, Xylon LogiCVC display controller, Mediatek's MT7621 SDRAM memory controller, and Apple M1 PCIe host - Run schema checks for %.dtb targets - Improve build time when using DT_SCHEMA_FILES - Improve error message when dtschema is not found - Various doc reference fixes in MAINTAINERS - Convert architectures to common CPU h/w ID parsing function of_get_cpu_hwid(). - Allow for empty NUMA node IDs which may be hotplugged - Cleanup of __fdt_scan_reserved_mem() - Constify device_node parameters - Update dtc to upstream v1.6.1-19-g0a3a9d3449c8. Adds new checks 'node_name_vs_property_name' and 'interrupt_map'. - Enable dtc 'unit_address_format' warning by default - Fix unittest EXPECT text for gpio hog errors * tag 'devicetree-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (97 commits) dt-bindings: net: ti,bluetooth: Document default max-speed dt-bindings: pci: rcar-pci-ep: Document r8a7795 dt-bindings: net: qcom,ipa: IPA does support up to two iommus of/fdt: Remove of_scan_flat_dt() usage for __fdt_scan_reserved_mem() of: unittest: document intentional interrupt-map provider build warning of: unittest: fix EXPECT text for gpio hog errors of/unittest: Disable new dtc node_name_vs_property_name and interrupt_map warnings scripts/dtc: Update to upstream version v1.6.1-19-g0a3a9d3449c8 dt-bindings: arm: firmware: tlm,trusted-foundations: Convert txt bindings to yaml dt-bindings: display: tilcd: Fix endpoint addressing in example dt-bindings: input: microchip,cap11xx: Convert txt bindings to yaml dt-bindings: ufs: exynos-ufs: add exynosautov9 compatible dt-bindings: ufs: exynos-ufs: add io-coherency property dt-bindings: mips: convert Ralink SoCs and boards to schema dt-bindings: display: xilinx: Fix example with psgtr dt-bindings: net: nfc: nxp,pn544: Convert txt bindings to yaml dt-bindings: Add a help message when dtschema tools are missing dt-bindings: bus: ti-sysc: Update to use yaml binding dt-bindings: sram: Allow numbers in sram region node name dt-bindings: display: Document the Xylon LogiCVC display controller ...
2021-11-02Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: - Rejig task/thread info to place thread info in task struct - Amba bus cleanups (removing unused functions) - Handle Amba device probe without IRQ domains - Parse linux,usable-memory-range in decompressor - Mark OCRAM as read-only after initialisation - Refactor page fault handling - Fix PXN handling with LPAE kernels - Warning and build fixes from Arnd * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (32 commits) ARM: 9151/1: Thumb2: avoid __builtin_thread_pointer() on Clang ARM: 9150/1: Fix PID_IN_CONTEXTIDR regression when THREAD_INFO_IN_TASK=y ARM: 9147/1: add printf format attribute to early_print() ARM: 9146/1: RiscPC needs older gcc version ARM: 9145/1: patch: fix BE32 compilation ARM: 9144/1: forbid ftrace with clang and thumb2_kernel ARM: 9143/1: add CONFIG_PHYS_OFFSET default values ARM: 9142/1: kasan: work around LPAE build warning ARM: 9140/1: allow compile-testing without machine record ARM: 9137/1: disallow CONFIG_THUMB with ARMv4 ARM: 9136/1: ARMv7-M uses BE-8, not BE-32 ARM: 9135/1: kprobes: address gcc -Wempty-body warning ARM: 9101/1: sa1100/assabet: convert LEDs to gpiod APIs ARM: 9131/1: mm: Fix PXN process with LPAE feature ARM: 9130/1: mm: Provide die_kernel_fault() helper ARM: 9126/1: mm: Kill page table base print in show_pte() ARM: 9127/1: mm: Cleanup access_error() ARM: 9129/1: mm: Kill task_struct argument for __do_page_fault() ARM: 9128/1: mm: Refactor the __do_page_fault() ARM: imx6: mark OCRAM mapping read-only ...
2021-11-02Merge branches 'devel-stable' and 'misc' into for-linusRussell King (Oracle)
2021-11-01Merge tag 'trace-v5.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - kprobes: Restructured stack unwinder to show properly on x86 when a stack dump happens from a kretprobe callback. - Fix to bootconfig parsing - Have tracefs allow owner and group permissions by default (only denying others). There's been pressure to allow non root to tracefs in a controlled fashion, and using groups is probably the safest. - Bootconfig memory managament updates. - Bootconfig clean up to have the tools directory be less dependent on changes in the kernel tree. - Allow perf to be traced by function tracer. - Rewrite of function graph tracer to be a callback from the function tracer instead of having its own trampoline (this change will happen on an arch by arch basis, and currently only x86_64 implements it). - Allow multiple direct trampolines (bpf hooks to functions) be batched together in one synchronization. - Allow histogram triggers to add variables that can perform calculations against the event's fields. - Use the linker to determine architecture callbacks from the ftrace trampoline to allow for proper parameter prototypes and prevent warnings from the compiler. - Extend histogram triggers to key off of variables. - Have trace recursion use bit magic to determine preempt context over if branches. - Have trace recursion disable preemption as all use cases do anyway. - Added testing for verification of tracing utilities. - Various small clean ups and fixes. * tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (101 commits) tracing/histogram: Fix semicolon.cocci warnings tracing/histogram: Fix documentation inline emphasis warning tracing: Increase PERF_MAX_TRACE_SIZE to handle Sentinel1 and docker together tracing: Show size of requested perf buffer bootconfig: Initialize ret in xbc_parse_tree() ftrace: do CPU checking after preemption disabled ftrace: disable preemption when recursion locked tracing/histogram: Document expression arithmetic and constants tracing/histogram: Optimize division by a power of 2 tracing/histogram: Covert expr to const if both operands are constants tracing/histogram: Simplify handling of .sym-offset in expressions tracing: Fix operator precedence for hist triggers expression tracing: Add division and multiplication support for hist triggers tracing: Add support for creating hist trigger variables from literal selftests/ftrace: Stop tracing while reading the trace file by default MAINTAINERS: Update KPROBES and TRACING entries test_kprobes: Move it from kernel/ to lib/ docs, kprobes: Remove invalid URL and add new reference samples/kretprobes: Fix return value if register_kretprobe() failed lib/bootconfig: Fix the xbc_get_info kerneldoc ...
2021-11-01Merge tag 'sched-core-2021-11-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Thomas Gleixner: - Revert the printk format based wchan() symbol resolution as it can leak the raw value in case that the symbol is not resolvable. - Make wchan() more robust and work with all kind of unwinders by enforcing that the task stays blocked while unwinding is in progress. - Prevent sched_fork() from accessing an invalid sched_task_group - Improve asymmetric packing logic - Extend scheduler statistics to RT and DL scheduling classes and add statistics for bandwith burst to the SCHED_FAIR class. - Properly account SCHED_IDLE entities - Prevent a potential deadlock when initial priority is assigned to a newly created kthread. A recent change to plug a race between cpuset and __sched_setscheduler() introduced a new lock dependency which is now triggered. Break the lock dependency chain by moving the priority assignment to the thread function. - Fix the idle time reporting in /proc/uptime for NOHZ enabled systems. - Improve idle balancing in general and especially for NOHZ enabled systems. - Provide proper interfaces for live patching so it does not have to fiddle with scheduler internals. - Add cluster aware scheduling support. - A small set of tweaks for RT (irqwork, wait_task_inactive(), various scheduler options and delaying mmdrop) - The usual small tweaks and improvements all over the place * tag 'sched-core-2021-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits) sched/fair: Cleanup newidle_balance sched/fair: Remove sysctl_sched_migration_cost condition sched/fair: Wait before decaying max_newidle_lb_cost sched/fair: Skip update_blocked_averages if we are defering load balance sched/fair: Account update_blocked_averages in newidle_balance cost x86: Fix __get_wchan() for !STACKTRACE sched,x86: Fix L2 cache mask sched/core: Remove rq_relock() sched: Improve wake_up_all_idle_cpus() take #2 irq_work: Also rcuwait for !IRQ_WORK_HARD_IRQ on PREEMPT_RT irq_work: Handle some irq_work in a per-CPU thread on PREEMPT_RT irq_work: Allow irq_work_sync() to sleep if irq_work() no IRQ support. sched/rt: Annotate the RT balancing logic irqwork as IRQ_WORK_HARD_IRQ sched: Add cluster scheduler level for x86 sched: Add cluster scheduler level in core and related Kconfig for ARM64 topology: Represent clusters of CPUs within a die sched: Disable -Wunused-but-set-variable sched: Add wrapper for get_wchan() to keep task blocked x86: Fix get_wchan() to support the ORC unwinder proc: Use task_is_running() for wchan in /proc/$pid/stat ...
2021-11-01Merge tag 'irq-core-2021-10-31' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Updates for the interrupt subsystem: Core changes: - Prevent a potential deadlock when initial priority is assigned to a newly created interrupt thread. A recent change to plug a race between cpuset and __sched_setscheduler() introduced a new lock dependency which is now triggered. Break the lock dependency chain by moving the priority assignment to the thread function. - A couple of small updates to make the irq core RT safe. - Confine the irq_cpu_online/offline() API to the only left unfixable user Cavium Octeon so that it does not grow new usage. - A small documentation update Driver changes: - A large cross architecture rework to move irq_enter/exit() into the architecture code to make addressing the NOHZ_FULL/RCU issues simpler. - The obligatory new irq chip driver for Microchip EIC - Modularize a few irq chip drivers - Expand usage of devm_*() helpers throughout the driver code - The usual small fixes and improvements all over the place" * tag 'irq-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) h8300: Fix linux/irqchip.h include mess dt-bindings: irqchip: renesas-irqc: Document r8a774e1 bindings MIPS: irq: Avoid an unused-variable error genirq: Hide irq_cpu_{on,off}line() behind a deprecated option irqchip/mips-gic: Get rid of the reliance on irq_cpu_online() MIPS: loongson64: Drop call to irq_cpu_offline() irq: remove handle_domain_{irq,nmi}() irq: remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY irq: riscv: perform irqentry in entry code irq: openrisc: perform irqentry in entry code irq: csky: perform irqentry in entry code irq: arm64: perform irqentry in entry code irq: arm: perform irqentry in entry code irq: add a (temporary) CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY irq: nds32: avoid CONFIG_HANDLE_DOMAIN_IRQ irq: arc: avoid CONFIG_HANDLE_DOMAIN_IRQ irq: add generic_handle_arch_irq() irq: unexport handle_irq_desc() irq: simplify handle_domain_{irq,nmi}() irq: mips: simplify do_domain_IRQ() ...
2021-10-25Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM fixes from Russell King: - Fix clang-related relocation warning in futex code - Fix incorrect use of get_kernel_nofault() - Fix bad code generation in __get_user_check() when kasan is enabled - Ensure TLB function table is correctly aligned - Remove duplicated string function definitions in decompressor - Fix link-time orphan section warnings - Fix old-style function prototype for arch_init_kprobes() - Only warn about XIP address when not compile testing - Handle BE32 big endian for keystone2 remapping * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 9148/1: handle CONFIG_CPU_ENDIAN_BE32 in arch/arm/kernel/head.S ARM: 9141/1: only warn about XIP address when not compile testing ARM: 9139/1: kprobes: fix arch_init_kprobes() prototype ARM: 9138/1: fix link warning with XIP + frame-pointer ARM: 9134/1: remove duplicate memcpy() definition ARM: 9133/1: mm: proc-macros: ensure *_tlb_fns are 4B aligned ARM: 9132/1: Fix __get_user_check failure with ARM KASAN images ARM: 9125/1: fix incorrect use of get_kernel_nofault() ARM: 9122/1: select HAVE_FUTEX_CMPXCHG
2021-10-25ARM: 9140/1: allow compile-testing without machine recordArnd Bergmann
A lot of randconfig builds end up not selecting any machine type at all. This is generally fine for the purpose of compile testing, but of course it means that the kernel is not usable on actual hardware, and it causes a warning about this fact. As most of the build bots now force-enable CONFIG_COMPILE_TEST for randconfig builds, use that as a guard to control whether we warn on this type of broken configuration. We could do the same for the missing-cpu-type warning, but those configurations fail to build much earlier. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-10-25ARM: 9148/1: handle CONFIG_CPU_ENDIAN_BE32 in arch/arm/kernel/head.SLABBE Corentin
My intel-ixp42x-welltech-epbx100 no longer boot since 4.14. This is due to commit 463dbba4d189 ("ARM: 9104/2: Fix Keystone 2 kernel mapping regression") which forgot to handle CONFIG_CPU_ENDIAN_BE32 as possible BE config. Suggested-by: Krzysztof Hałasa <khalasa@piap.pl> Fixes: 463dbba4d189 ("ARM: 9104/2: Fix Keystone 2 kernel mapping regression") Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-10-25irq: arm: perform irqentry in entry codeMark Rutland
In preparation for removing HANDLE_DOMAIN_IRQ_IRQENTRY, have arch/arm perform all the irqentry accounting in its entry code. For configurations with CONFIG_GENERIC_IRQ_MULTI_HANDLER, we can use generic_handle_arch_irq(). Other than asm_do_IRQ(), all C calls to handle_IRQ() are from irqchip handlers which will be called from generic_handle_arch_irq(), so to avoid double accounting IRQ entry, the entry logic is moved from handle_IRQ() into asm_do_IRQ(). For ARMv7M the entry assembly is tightly coupled with the NVIC irqchip, and while the entry code should logically live under arch/arm/, moving the entry logic there makes things more convoluted. So for now, place the entry logic in the NVIC irqchip, but separated into a separate function to make the split of responsibility clear. For all other configurations without CONFIG_GENERIC_IRQ_MULTI_HANDLER, IRQ entry is already handled in arch code, and requires no changes. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de>
2021-10-22ARM: Recover kretprobe modified return address in stacktraceMasami Hiramatsu
Since the kretprobe replaces the function return address with the kretprobe_trampoline on the stack, arm unwinder shows it instead of the correct return address. This finds the correct return address from the per-task kretprobe_instances list and verify it is in between the caller fp and callee fp. Note that this supports both GCC and clang if CONFIG_FRAME_POINTER=y and CONFIG_ARM_UNWIND=n. For the ARM unwinder, this is still not working correctly. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-22ARM: clang: Do not rely on lr register for stacktraceMasami Hiramatsu
Currently the stacktrace on clang compiled arm kernel uses the 'lr' register to find the first frame address from pt_regs. However, that is wrong after calling another function, because the 'lr' register is used by 'bl' instruction and never be recovered. As same as gcc arm kernel, directly use the frame pointer (r11) of the pt_regs to find the first frame address. Note that this fixes kretprobe stacktrace issue only with CONFIG_UNWINDER_FRAME_POINTER=y. For the CONFIG_UNWINDER_ARM, we need another fix. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-20ARM: Use of_get_cpu_hwid()Rob Herring
Replace the open coded parsing of CPU nodes' 'reg' property with of_get_cpu_hwid(). This change drops an error message for missing 'reg' property, but that should not be necessary as the DT tools will ensure 'reg' is present. Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Rob Herring <robh@kernel.org> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20211006164332.1981454-3-robh@kernel.org
2021-10-19ARM: 9141/1: only warn about XIP address when not compile testingArnd Bergmann
In randconfig builds, we sometimes come across this warning: arm-linux-gnueabi-ld: XIP start address may cause MPU programming issues While this is helpful for actual systems to figure out why it fails, the warning does not provide any benefit for build testing, so guard it in a check for CONFIG_COMPILE_TEST, which is usually set on randconfig builds. Fixes: 216218308cfb ("ARM: 8713/1: NOMMU: Support MPU in XIP configuration") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-10-19ARM: 9138/1: fix link warning with XIP + frame-pointerArnd Bergmann
When frame pointers are used instead of the ARM unwinder, and the kernel is built using clang with an external assembler and CONFIG_XIP_KERNEL, every file produces two warnings like: arm-linux-gnueabi-ld: warning: orphan section `.ARM.extab' from `net/mac802154/util.o' being placed in section `.ARM.extab' arm-linux-gnueabi-ld: warning: orphan section `.ARM.exidx' from `net/mac802154/util.o' being placed in section `.ARM.exidx' The same fix was already merged for the normal (non-XIP) linker script, with a longer description. Fixes: c39866f268f8 ("arm/build: Always handle .ARM.exidx and .ARM.extab sections") Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-10-19ARM: 9125/1: fix incorrect use of get_kernel_nofault()Ard Biesheuvel
Commit 344179fc7ef4 ("ARM: 9106/1: traps: use get_kernel_nofault instead of set_fs()") replaced an occurrence of __get_user() with get_kernel_nofault(), but inverted the sense of the conditional in the process, resulting in no values to be printed at all. I.e., every exception stack now looks like this: Exception stack(0xc18d1fb0 to 0xc18d1ff8) 1fa0: ???????? ???????? ???????? ???????? 1fc0: ???????? ???????? ???????? ???????? ???????? ???????? ???????? ???????? 1fe0: ???????? ???????? ???????? ???????? ???????? ???????? which is rather unhelpful. Fixes: 344179fc7ef4 ("ARM: 9106/1: traps: use get_kernel_nofault instead of set_fs()") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-10-19ARM: 9125/1: fix incorrect use of get_kernel_nofault()Ard Biesheuvel
Commit 344179fc7ef4 ("ARM: 9106/1: traps: use get_kernel_nofault instead of set_fs()") replaced an occurrence of __get_user() with get_kernel_nofault(), but inverted the sense of the conditional in the process, resulting in no values to be printed at all. I.e., every exception stack now looks like this: Exception stack(0xc18d1fb0 to 0xc18d1ff8) 1fa0: ???????? ???????? ???????? ???????? 1fc0: ???????? ???????? ???????? ???????? ???????? ???????? ???????? ???????? 1fe0: ???????? ???????? ???????? ???????? ???????? ???????? which is rather unhelpful. Fixes: 344179fc7ef4 ("ARM: 9106/1: traps: use get_kernel_nofault instead of set_fs()") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>