linux/arch/arm/kernel, branch v4.9

Revert "arm: move exports to definitions"

2016-11-23T10:00:03Z

This reverts commit 4dd1837d7589f468ed109556513f476e7a7f9121. Moving the exports for assembly code into the assembly files breaks KSYM trimming, but also breaks modversions. While fixing the KSYM trimming is trivial, fixing modversions brings us to a technically worse position that we had prior to the above change: - We end up with the prototype definitions divorsed from everything else, which means that adding or removing assembly level ksyms become more fragile: * if adding a new assembly ksyms export, a missed prototype in asm-prototypes.h results in a successful build if no module in the selected configuration makes use of the symbol. * when removing a ksyms export, asm-prototypes.h will get forgotten, with armksyms.c, you'll get a build error if you forget to touch the file. - We end up with the same amount of include files and prototypes, they're just in a header file instead of a .c file with their exports. As for lines of code, we don't get much of a size reduction: (original commit) 47 files changed, 131 insertions(+), 208 deletions(-) (fix for ksyms trimming) 7 files changed, 18 insertions(+), 5 deletions(-) (two fixes for modversions) 1 file changed, 34 insertions(+) 3 files changed, 7 insertions(+), 2 deletions(-) which results in a net total of only 25 lines deleted. As there does not seem to be much benefit from this change of approach, revert the change. Signed-off-by: Russell King

ARM: Fix XIP kernels

2016-11-16T23:51:19Z

Commit 7619751f8c90 ("ARM: 8595/2: apply more __ro_after_init") caused a regression with XIP kernels by moving the __ro_after_init data into the read-only section. With XIP kernels, the read-only section is located in read-only memory from the very beginning. Work around this by moving the __ro_after_init data back into the .data section, which will be in RAM, and hence will be writable. It should be noted that in doing so, this remains writable after init. Fixes: 7619751f8c90 ("ARM: 8595/2: apply more __ro_after_init") Reported-by: Andrea Merello Tested-by: Andrea Merello [ XIP stm32 ] Tested-by: Alexandre Torgue Signed-off-by: Russell King

ARM: fix backtrace

2016-11-15T15:25:39Z

Recent kernels have changed their behaviour to be more inconsistent when handling printk continuations. With todays kernels, the output looks sane on the console, but dmesg splits individual printk()s which do not have the KERN_CONT prefix into separate lines. Since the assembly code is not trivial to add the KERN_CONT, and we ideally want to avoid using KERN_CONT (as multiple printk()s can race between different threads), convert the assembly dumping the register values to C code, and have the C code build the output a line at a time before dumping to the console. This avoids the KERN_CONT issue, and also avoids situations where the output is intermixed with other console activity. Signed-off-by: Russell King

ARM: wire up new pkey syscalls

2016-10-19T09:18:47Z

Wire up the new pkey syscalls for ARM. Signed-off-by: Russell King

Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild

2016-10-14T21:26:58Z

Pull kbuild updates from Michal Marek: - EXPORT_SYMBOL for asm source by Al Viro. This does bring a regression, because genksyms no longer generates checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is working on a patch to fix this. Plus, we are talking about functions like strcpy(), which rarely change prototypes. - Fixes for PPC fallout of the above by Stephen Rothwell and Nick Piggin - fixdep speedup by Alexey Dobriyan. - preparatory work by Nick Piggin to allow architectures to build with -ffunction-sections, -fdata-sections and --gc-sections - CONFIG_THIN_ARCHIVES support by Stephen Rothwell - fix for filenames with colons in the initramfs source by me. * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits) initramfs: Escape colons in depfile ppc: there is no clear_pages to export powerpc/64: whitelist unresolved modversions CRCs kbuild: -ffunction-sections fix for archs with conflicting sections kbuild: add arch specific post-link Makefile kbuild: allow archs to select link dead code/data elimination kbuild: allow architectures to use thin archives instead of ld -r kbuild: Regenerate genksyms lexer kbuild: genksyms fix for typeof handling fixdep: faster CONFIG_ search ia64: move exports to definitions sparc32: debride memcpy.S a bit [sparc] unify 32bit and 64bit string.h sparc: move exports to definitions ppc: move exports to definitions arm: move exports to definitions s390: move exports to definitions m68k: move exports to definitions alpha: move exports to actual definitions x86: move exports to actual definitions ...

ARM: use simpler API for random address requests

2016-10-11T22:06:32Z

Currently, all callers to randomize_range() set the length to 0 and calculate end by adding a constant to the start address. We can simplify the API to remove a bunch of needless checks and variables. Use the new randomize_addr(start, range) call to set the requested address. Link: http://lkml.kernel.org/r/20160803233913.32511-4-jason@lakedaemon.net Signed-off-by: Jason Cooper Acked-by: Kees Cook Cc: "Russell King - ARM Linux" Cc: "Theodore Ts'o" Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nmi_backtrace: generate one-line reports for idle cpus

2016-10-08T01:46:30Z

When doing an nmi backtrace of many cores, most of which are idle, the output is a little overwhelming and very uninformative. Suppress messages for cpus that are idling when they are interrupted and just emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN". We do this by grouping all the cpuidle code together into a new .cpuidle.text section, and then checking the address of the interrupted PC to see if it lies within that section. This commit suitably tags x86 and tile idle routines, and only adds in the minimal framework for other architectures. Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com Signed-off-by: Chris Metcalf Acked-by: Peter Zijlstra (Intel) Tested-by: Peter Zijlstra (Intel) Tested-by: Daniel Thompson [arm] Tested-by: Petr Mladek Cc: Aaron Tomlin Cc: Peter Zijlstra (Intel) Cc: "Rafael J. Wysocki" Cc: Russell King Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nmi_backtrace: do a local dump_stack() instead of a self-NMI

2016-10-08T01:46:30Z

Currently on arm there is code that checks whether it should call dump_stack() explicitly, to avoid trying to raise an NMI when the current context is not preemptible by the backtrace IPI. Similarly, the forthcoming arch/tile support uses an IPI mechanism that does not support generating an NMI to self. Accordingly, move the code that guards this case into the generic mechanism, and invoke it unconditionally whenever we want a backtrace of the current cpu. It seems plausible that in all cases, dump_stack() will generate better information than generating a stack from the NMI handler. The register state will be missing, but that state is likely not particularly helpful in any case. Or, if we think it is helpful, we should be capturing and emitting the current register state in all cases when regs == NULL is passed to nmi_cpu_backtrace(). Link: http://lkml.kernel.org/r/1472487169-14923-3-git-send-email-cmetcalf@mellanox.com Signed-off-by: Chris Metcalf Tested-by: Daniel Thompson [arm] Reviewed-by: Petr Mladek Acked-by: Aaron Tomlin Cc: "Rafael J. Wysocki" Cc: Russell King Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nmi_backtrace: add more trigger_*_cpu_backtrace() methods

2016-10-08T01:46:30Z

Patch series "improvements to the nmi_backtrace code" v9. This patch series modifies the trigger_xxx_backtrace() NMI-based remote backtracing code to make it more flexible, and makes a few small improvements along the way. The motivation comes from the task isolation code, where there are scenarios where we want to be able to diagnose a case where some cpu is about to interrupt a task-isolated cpu. It can be helpful to see both where the interrupting cpu is, and also an approximation of where the cpu that is being interrupted is. The nmi_backtrace framework allows us to discover the stack of the interrupted cpu. I've tested that the change works as desired on tile, and build-tested x86, arm, mips, and sparc64. For x86 I confirmed that the generic cpuidle stuff as well as the architecture-specific routines are in the new cpuidle section. For arm, mips, and sparc I just build-tested it and made sure the generic cpuidle routines were in the new cpuidle section, but I didn't attempt to figure out which the platform-specific idle routines might be. That might be more usefully done by someone with platform experience in follow-up patches. This patch (of 4): Currently you can only request a backtrace of either all cpus, or all cpus but yourself. It can also be helpful to request a remote backtrace of a single cpu, and since we want that, the logical extension is to support a cpumask as the underlying primitive. This change modifies the existing lib/nmi_backtrace.c code to take a cpumask as its basic primitive, and modifies the linux/nmi.h code to use the new "cpumask" method instead. The existing clients of nmi_backtrace (arm and x86) are converted to using the new cpumask approach in this change. The other users of the backtracing API (sparc64 and mips) are converted to use the cpumask approach rather than the all/allbutself approach. The mips code ignored the "include_self" boolean but with this change it will now also dump a local backtrace if requested. Link: http://lkml.kernel.org/r/1472487169-14923-2-git-send-email-cmetcalf@mellanox.com Signed-off-by: Chris Metcalf Tested-by: Daniel Thompson [arm] Reviewed-by: Aaron Tomlin Reviewed-by: Petr Mladek Cc: "Rafael J. Wysocki" Cc: Russell King Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Ralf Baechle Cc: David Miller Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

2016-10-06T14:59:37Z

Pull ARM updates from Russell King: - Correct ARMs dma-mapping to use the correct printk format strings. - Avoid defining OBJCOPYFLAGS globally which upsets lkdtm rodata testing. - Cleanups to ARMs asm/memory.h include. - L2 cache cleanups. - Allow flat nommu binaries to be executed on ARM MMU systems. - Kernel hardening - add more read-only after init annotations, including making some kernel vdso variables const. - Ensure AMBA primecell clocks are appropriately defaulted. - ARM breakpoint cleanup. - Various StrongARM 11x0 and companion chip (SA1111) updates to bring this legacy platform to use more modern APIs for (eg) GPIOs and interrupts, which will allow us in the future to reduce some of the board-level driver clutter and elimate function callbacks into board code via platform data. There still appears to be interest in these platforms! - Remove the now redundant secure_flush_area() API. - Module PLT relocation optimisations. Ard says: This series of 4 patches optimizes the ARM PLT generation code that is invoked at module load time, to get rid of the O(n^2) algorithm that results in pathological load times of 10 seconds or more for large modules on certain STB platforms. - ARMv7M cache maintanence support. - L2 cache PMU support * 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (35 commits) ARM: sa1111: provide to_sa1111_device() macro ARM: sa1111: add sa1111_get_irq() ARM: sa1111: clean up duplication in IRQ chip implementation ARM: sa1111: implement a gpio_chip for SA1111 GPIOs ARM: sa1111: move irq cleanup to separate function ARM: sa1111: use devm_clk_get() ARM: sa1111: use devm_kzalloc() ARM: sa1111: ensure we only touch RAB bus type devices when removing ARM: 8611/1: l2x0: add PMU support ARM: 8610/1: V7M: Add dsb before jumping in handler mode ARM: 8609/1: V7M: Add support for the Cortex-M7 processor ARM: 8608/1: V7M: Indirect proc_info construction for V7M CPUs ARM: 8607/1: V7M: Wire up caches for V7M processors with cache support. ARM: 8606/1: V7M: introduce cache operations ARM: 8605/1: V7M: fix notrace variant of save_and_disable_irqs ARM: 8604/1: V7M: Add support for reading the CTR with read_cpuid_cachetype() ARM: 8603/1: V7M: Add addresses for mem-mapped V7M cache operations ARM: 8602/1: factor out CSSELR/CCSIDR operations that use cp15 directly ARM: kernel: avoid brute force search on PLT generation ARM: kernel: sort relocation sections before allocating PLTs ...