lwn.git/arch/mips, branch docs-4.19

MIPS: Add ksig argument to rseq_{signal_deliver,handle_notify_resume}

2018-06-24T17:33:03+00:00

Commit 784e0300fe9f ("rseq: Avoid infinite recursion when delivering SIGSEGV") added a new ksig argument to the rseq_signal_deliver() & rseq_handle_notify_resume() functions, and was merged in v4.18-rc2. Meanwhile MIPS support for restartable sequences was also merged in v4.18-rc2 with commit 9ea141ad5471 ("MIPS: Add support for restartable sequences"), and therefore didn't get updated for the API change. This results in build failures like the following: CC arch/mips/kernel/signal.o arch/mips/kernel/signal.c: In function 'handle_signal': arch/mips/kernel/signal.c:804:22: error: passing argument 1 of 'rseq_signal_deliver' from incompatible pointer type [-Werror=incompatible-pointer-types] rseq_signal_deliver(regs); ^~~~ In file included from ./include/linux/context_tracking.h:5, from arch/mips/kernel/signal.c:12: ./include/linux/sched.h:1811:56: note: expected 'struct ksignal *' but argument is of type 'struct pt_regs *' static inline void rseq_signal_deliver(struct ksignal *ksig, ~~~~~~~~~~~~~~~~^~~~ arch/mips/kernel/signal.c:804:2: error: too few arguments to function 'rseq_signal_deliver' rseq_signal_deliver(regs); ^~~~~~~~~~~~~~~~~~~ Fix this by adding the ksig argument as was done for other architectures in commit 784e0300fe9f ("rseq: Avoid infinite recursion when delivering SIGSEGV"). Signed-off-by: Paul Burton Acked-by: Mathieu Desnoyers Patchwork: https://patchwork.linux-mips.org/patch/19603/ Cc: James Hogan Cc: Ralf Baechle Cc: Peter Zijlstra Cc: Paul E. McKenney Cc: Boqun Feng Cc: Will Deacon Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org

MIPS: Wire up io_pgetevents syscall

2018-06-20T04:14:29+00:00

Wire up the io_pgetevents syscall that was introduced by commit 7a074e96dee6 ("aio: implement io_pgetevents"). Signed-off-by: Paul Burton Patchwork: https://patchwork.linux-mips.org/patch/19593/ Cc: James Hogan Cc: Ralf Baechle Cc: linux-mips@linux-mips.org

MIPS: Wire up the restartable sequences (rseq) syscall

2018-06-20T04:14:09+00:00

Wire up the restartable sequences (rseq) syscall for MIPS. This was introduced by commit d7822b1e24f2 ("rseq: Introduce restartable sequences system call") & MIPS now supports the prerequisites. Signed-off-by: Paul Burton Reviewed-by: James Hogan Patchwork: https://patchwork.linux-mips.org/patch/19525/ Cc: Ralf Baechle Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: Paul E. McKenney Cc: Boqun Feng Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org

MIPS: Add syscall detection for restartable sequences

2018-06-20T04:13:56+00:00

Syscalls are not allowed inside restartable sequences, so add a call to rseq_syscall() at the very beginning of the system call exit path when CONFIG_DEBUG_RSEQ=y. This will help us to detect whether there is a syscall issued erroneously inside a restartable sequence. Signed-off-by: Paul Burton Reviewed-by: James Hogan Patchwork: https://patchwork.linux-mips.org/patch/19522/ Cc: Ralf Baechle Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: Paul E. McKenney Cc: Boqun Feng Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org

MIPS: Add support for restartable sequences

2018-06-20T04:13:17+00:00

Implement support for restartable sequences on MIPS, which requires 3 simple things: - Call rseq_handle_notify_resume() on return to userspace if TIF_NOTIFY_RESUME is set. - Call rseq_signal_deliver() to fixup the pre-signal stack frame when a signal is delivered whilst executing a restartable sequence critical section. - Select CONFIG_HAVE_RSEQ. Signed-off-by: Paul Burton Reviewed-by: James Hogan Patchwork: https://patchwork.linux-mips.org/patch/19523/ Cc: Ralf Baechle Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: Paul E. McKenney Cc: Boqun Feng Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org

MIPS: io: Add barrier after register read in inX()

2018-06-20T02:39:19+00:00

While a barrier is present in the outX() functions before the register write, a similar barrier is missing in the inX() functions after the register read. This could allow memory accesses following inX() to observe stale data. This patch is very similar to commit a1cc7034e33d12dc1 ("MIPS: io: Add barrier after register read in readX()"). Because war_io_reorder_wmb() is both used by writeX() and outX(), if readX() need a barrier then so does inX(). Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen Patchwork: https://patchwork.linux-mips.org/patch/19516/ Signed-off-by: Paul Burton Cc: James Hogan Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang Cc: Zhangjin Wu Cc: Huacai Chen

mips: ftrace: fix static function graph tracing

2018-06-19T22:00:12+00:00

ftrace_graph_caller was never run after calling ftrace_trace_function, breaking the function graph tracer. Fix this, bringing it in line with the x86 implementation. While we're at it, also streamline the control flow of _mcount a bit to reduce the number of branches. This issue was reported before: https://www.linux-mips.org/archives/linux-mips/2014-11/msg00295.html Signed-off-by: Matthias Schiffer Tested-by: Matt Redfearn Patchwork: https://patchwork.linux-mips.org/patch/18929/ Signed-off-by: Paul Burton Cc: stable@vger.kernel.org # v3.17+

MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum

2018-06-18T21:19:50+00:00

The erratum and workaround are described by BCM5300X-ES300-RDS.pdf as below. R10: PCIe Transactions Periodically Fail Description: The BCM5300X PCIe does not maintain transaction ordering. This may cause PCIe transaction failure. Fix Comment: Add a dummy PCIe configuration read after a PCIe configuration write to ensure PCIe configuration access ordering. Set ES bit of CP0 configu7 register to enable sync function so that the sync instruction is functional. Resolution: hndpci.c: extpci_write_config() hndmips.c: si_mips_init() mipsinc.h CONF7_ES This is fixed by the CFE MIPS bcmsi chipset driver also for BCM47XX. Also the dummy PCIe configuration read is already implemented in the Linux BCMA driver. Enable ExternalSync in Config7 when CONFIG_BCMA_DRIVER_PCI_HOSTMODE=y too so that the sync instruction is externalised. Signed-off-by: Tokunori Ikegami Reviewed-by: Paul Burton Acked-by: Hauke Mehrtens Cc: Chris Packham Cc: Rafał Miłecki Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/19461/ Signed-off-by: James Hogan

MIPS: pb44: Fix i2c-gpio GPIO descriptor table

2018-06-18T21:19:50+00:00

I used bad names in my clumsiness when rewriting many board files to use GPIO descriptors instead of platform data. A few had the platform_device ID set to -1 which would indeed give the device name "i2c-gpio". But several had it set to >=0 which gives the names "i2c-gpio.0", "i2c-gpio.1" ... Fix the one affected board in the MIPS tree. Sorry. Fixes: b2e63555592f ("i2c: gpio: Convert to use descriptors") Reported-by: Simon Guinot Signed-off-by: Linus Walleij Reviewed-by: Paul Burton Cc: Ralf Baechle Cc: Wolfram Sang Cc: Simon Guinot Cc: linux-mips@linux-mips.org Cc: # 4.15+ Patchwork: https://patchwork.linux-mips.org/patch/19387/ Signed-off-by: James Hogan

Merge branch 'akpm' (patches from Andrew)

2018-06-14T23:51:42+00:00

Merge more updates from Andrew Morton: - MM remainders - various misc things - kcov updates * emailed patches from Andrew Morton : (27 commits) lib/test_printf.c: call wait_for_random_bytes() before plain %p tests hexagon: drop the unused variable zero_page_mask hexagon: fix printk format warning in setup.c mm: fix oom_kill event handling treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX mm: use octal not symbolic permissions ipc: use new return type vm_fault_t sysvipc/sem: mitigate semnum index against spectre v1 fault-injection: reorder config entries arm: port KCOV to arm sched/core / kcov: avoid kcov_area during task switch kcov: prefault the kcov_area kcov: ensure irq code sees a valid area kernel/relay.c: change return type to vm_fault_t exofs: avoid VLA in structures coredump: fix spam with zero VMA process fat: use fat_fs_error() instead of BUG_ON() in __fat_get_block() proc: skip branch in /proc/*/* lookup mremap: remove LATENCY_LIMIT from mremap to reduce the number of TLB shootdowns mm/memblock: add missing include ...