talos-obmc-linux/arch/xtensa/kernel, branch dev-5.0-raptor-04-16-2019

xtensa: fix get_wchan

2019-03-10T06:09:01+00:00

commit d90b88fd3653f1fb66ecc6571b860d5a5749fa56 upstream. Stack unwinding is implemented incorrectly in xtensa get_wchan: instead of extracting a0 and a1 registers from the spill location under the stack pointer it extracts a word pointed to by the stack pointer and subtracts 4 or 3 from it. Cc: stable@vger.kernel.org Signed-off-by: Max Filippov Signed-off-by: Greg Kroah-Hartman

xtensa: SMP: limit number of possible CPUs by NR_CPUS

2019-01-27T18:04:30+00:00

This fixes the following warning at boot when the kernel is booted on a board with more CPU cores than was configured in NR_CPUS: smp_init_cpus: Core Count = 8 smp_init_cpus: Core Id = 0 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at include/linux/cpumask.h:121 smp_init_cpus+0x54/0x74 Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.0.0-rc3-00015-g1459333f88a0 #124 Call Trace: __warn$part$3+0x6a/0x7c warn_slowpath_null+0x35/0x3c smp_init_cpus+0x54/0x74 setup_arch+0x1c0/0x1d0 start_kernel+0x44/0x310 _startup+0x107/0x107 Signed-off-by: Max Filippov

xtensa: SMP: mark each possible CPU as present

2019-01-26T10:02:14+00:00

Otherwise it is impossible to enable CPUs after booting with 'maxcpus' parameter. Signed-off-by: Max Filippov

xtensa: SMP: fix secondary CPU initialization

2019-01-26T10:02:13+00:00

- add missing memory barriers to the secondary CPU synchronization spin loops; add comment to the matching memory barrier in the boot_secondary and __cpu_die functions; - use READ_ONCE/WRITE_ONCE to access cpu_start_id/cpu_start_ccount instead of reading/writing them directly; - re-initialize cpu_running every time before starting secondary CPU to flush possible previous CPU startup results. Signed-off-by: Max Filippov

xtensa: SMP: fix ccount_timer_shutdown

2019-01-25T00:01:07+00:00

ccount_timer_shutdown is called from the atomic context in the secondary_start_kernel, resulting in the following BUG: BUG: sleeping function called from invalid context in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/1 Preemption disabled at: secondary_start_kernel+0xa1/0x130 Call Trace: ___might_sleep+0xe7/0xfc __might_sleep+0x41/0x44 synchronize_irq+0x24/0x64 disable_irq+0x11/0x14 ccount_timer_shutdown+0x12/0x20 clockevents_switch_state+0x82/0xb4 clockevents_exchange_device+0x54/0x60 tick_check_new_device+0x46/0x70 clockevents_register_device+0x8c/0xc8 clockevents_config_and_register+0x1d/0x2c local_timer_setup+0x75/0x7c secondary_start_kernel+0xb4/0x130 should_never_return+0x32/0x35 Use disable_irq_nosync instead of disable_irq to avoid it. This is safe because the ccount timer IRQ is per-CPU, and once IRQ is masked the ISR will not be called. Signed-off-by: Max Filippov

jump_label: move 'asm goto' support test to Kconfig

2019-01-06T00:46:51+00:00

Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label". The jump label is controlled by HAVE_JUMP_LABEL, which is defined like this: #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) # define HAVE_JUMP_LABEL #endif We can improve this by testing 'asm goto' support in Kconfig, then make JUMP_LABEL depend on CC_HAS_ASM_GOTO. Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will match to the real kernel capability. Signed-off-by: Masahiro Yamada Acked-by: Michael Ellerman (powerpc) Tested-by: Sedat Dilek

Remove 'type' argument from access_ok() function

2019-01-04T02:57:57+00:00

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds

Merge tag 'xtensa-20181228' of git://github.com/jcmvbkbc/linux-xtensa

2018-12-29T17:40:40+00:00

Pull Xtensa updates from Max Filippov: - switch to generated syscall table - switch ptrace to regsets, use regsets for core dumps - complete tracehook implementation - add syscall tracepoints support - add jumplabels support - add memtest support - drop unused/duplicated code from entry.S, ptrace.c, coprocessor.S, elf.h and syscall.h - clean up warnings caused by WSR/RSR macros - clean up DTC warnings about SPI controller node names in xtfpga.dtsi - simplify coprocessor.S - get rid of explicit 'l32r' instruction usage in assembly * tag 'xtensa-20181228' of git://github.com/jcmvbkbc/linux-xtensa: (25 commits) xtensa: implement jump_label support xtensa: implement syscall tracepoints xtensa: implement tracehook functions and enable HAVE_ARCH_TRACEHOOK xtensa: enable CORE_DUMP_USE_REGSET xtensa: implement TIE regset xtensa: implement task_user_regset_view xtensa: call do_syscall_trace_{enter,leave} selectively xtensa: use NO_SYSCALL instead of -1 xtensa: define syscall_get_arch() Move EM_XTENSA to uapi/linux/elf-em.h xtensa: support memtest xtensa: don't use l32r opcode directly xtensa: xtfpga.dtsi: fix dtc warnings about SPI xtensa: don't clear cpenable unconditionally on release xtensa: simplify coprocessor.S xtensa: clean up WSR*/RSR*/get_sr/set_sr xtensa: drop unused declarations from elf.h xtensa: clean up syscall.h xtensa: drop unused coprocessor helper functions xtensa: drop custom PTRACE_{PEEK,POKE}{TEXT,DATA} ...

Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping

2018-12-28T22:12:21+00:00

Pull DMA mapping updates from Christoph Hellwig: "A huge update this time, but a lot of that is just consolidating or removing code: - provide a common DMA_MAPPING_ERROR definition and avoid indirect calls for dma_map_* error checking - use direct calls for the DMA direct mapping case, avoiding huge retpoline overhead for high performance workloads - merge the swiotlb dma_map_ops into dma-direct - provide a generic remapping DMA consistent allocator for architectures that have devices that perform DMA that is not cache coherent. Based on the existing arm64 implementation and also used for csky now. - improve the dma-debug infrastructure, including dynamic allocation of entries (Robin Murphy) - default to providing chaining scatterlist everywhere, with opt-outs for the few architectures (alpha, parisc, most arm32 variants) that can't cope with it - misc sparc32 dma-related cleanups - remove the dma_mark_clean arch hook used by swiotlb on ia64 and replace it with the generic noncoherent infrastructure - fix the return type of dma_set_max_seg_size (Niklas Söderlund) - move the dummy dma ops for not DMA capable devices from arm64 to common code (Robin Murphy) - ensure dma_alloc_coherent returns zeroed memory to avoid kernel data leaks through userspace. We already did this for most common architectures, but this ensures we do it everywhere. dma_zalloc_coherent has been deprecated and can hopefully be removed after -rc1 with a coccinelle script" * tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping: (73 commits) dma-mapping: fix inverted logic in dma_supported dma-mapping: deprecate dma_zalloc_coherent dma-mapping: zero memory returned from dma_alloc_* sparc/iommu: fix ->map_sg return value sparc/io-unit: fix ->map_sg return value arm64: default to the direct mapping in get_arch_dma_ops PCI: Remove unused attr variable in pci_dma_configure ia64: only select ARCH_HAS_DMA_COHERENT_TO_PFN if swiotlb is enabled dma-mapping: bypass indirect calls for dma-direct vmd: use the proper dma_* APIs instead of direct methods calls dma-direct: merge swiotlb_dma_ops into the dma_direct code dma-direct: use dma_direct_map_page to implement dma_direct_map_sg dma-direct: improve addressability error reporting swiotlb: remove dma_mark_clean swiotlb: remove SWIOTLB_MAP_ERROR ACPI / scan: Refactor _CCA enforcement dma-mapping: factor out dummy DMA ops dma-mapping: always build the direct mapping code dma-mapping: move dma_cache_sync out of line dma-mapping: move various slow path functions out of line ...

xtensa: implement jump_label support

2018-12-20T22:44:38+00:00

Use 3-byte 'nop' and 'j' instructions that are always present. Don't let assembler mark a spot right after patchable 'j' instruction as unreachable and later put literals or padding bytes there. Add separate implementations of patch_text for SMP and UP cases, avoiding use of atomics on UP. Signed-off-by: Max Filippov