talos-obmc-linux/arch/mips/kernel, branch dev-4.13

MIPS: BMIPS: Fix missing cbr address

2017-11-15T09:09:17+00:00

commit ea4b3afe1eac8f88bb453798a084fba47a1f155a upstream. Fix NULL pointer access in BMIPS3300 RAC flush. Fixes: 738a3f79027b ("MIPS: BMIPS: Add early CPU initialization code") Signed-off-by: Jaedon Shin Reviewed-by: Florian Fainelli Cc: Kevin Cernekee Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16423/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman

MIPS: SMP: Fix deadlock & online race

2017-11-08T09:17:19+00:00

commit 9e8c399a88f0b87e41a894911475ed2a8f8dff9e upstream. Commit 6f542ebeaee0 ("MIPS: Fix race on setting and getting cpu_online_mask") effectively reverted commit 8f46cca1e6c06 ("MIPS: SMP: Fix possibility of deadlock when bringing CPUs online") and thus has reinstated the possibility of deadlock. The commit was based on testing of kernel v4.4, where the CPU hotplug core code issued a BUG() if the starting CPU is not marked online when the boot CPU returns from __cpu_up. The commit fixes this race (in v4.4), but re-introduces the deadlock situation. As noted in the commit message, upstream differs in this area. Commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu bring itself fully up") adds a completion event in the CPU hotplug core code, making this race impossible. However, people were unhappy with relying on the core code to do the right thing. To address the issues both commits were trying to fix, add a second completion event in the MIPS smp hotplug path. It removes the possibility of a race, since the MIPS smp hotplug code now synchronises both the boot and secondary CPUs before they return to the hotplug core code. It also addresses the deadlock by ensuring that the secondary CPU is not marked online before it's counters are synchronised. This fix should also be backported to fix the race condition introduced by the backport of commit 8f46cca1e6c06 ("MIPS: SMP: Fix possibility of deadlock when bringing CPUs online"), through really that race only existed before commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu bring itself fully up"). Signed-off-by: Matt Redfearn Fixes: 6f542ebeaee0 ("MIPS: Fix race on setting and getting cpu_online_mask") CC: Matija Glavinic Pecotic Patchwork: https://patchwork.linux-mips.org/patch/17376/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman

MIPS: smp-cmp: Use right include for task_struct

2017-11-08T09:17:18+00:00

commit f677b77050c144bd4c515b91ea48bd0efe82355e upstream. When task_struct was moved, this MIPS code was neglected. Evidently nobody is using it anymore. This fixes this build error: In file included from ./arch/mips/include/asm/thread_info.h:15:0, from ./include/linux/thread_info.h:37, from ./include/asm-generic/current.h:4, from ./arch/mips/include/generated/asm/current.h:1, from ./include/linux/sched.h:11, from arch/mips/kernel/smp-cmp.c:22: arch/mips/kernel/smp-cmp.c: In function ‘cmp_boot_secondary’: ./arch/mips/include/asm/processor.h:384:41: error: implicit declaration of function ‘task_stack_page’ [-Werror=implicit-function-declaration] #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \ ^ arch/mips/kernel/smp-cmp.c:84:21: note: in expansion of macro ‘__KSTK_TOS’ unsigned long sp = __KSTK_TOS(idle); ^~~~~~~~~~ Fixes: f3ac60671954 ("sched/headers: Move task-stack related APIs from to ") Signed-off-by: Jason A. Donenfeld Patchwork: https://patchwork.linux-mips.org/patch/17522/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman

MIPS: Fix perf event init

2017-10-05T07:47:29+00:00

commit fd0b19ed5389187829b854900511c9195875bb42 upstream. Commit c311c797998c ("cpumask: make "nr_cpumask_bits" unsigned") modified mipspmu_event_init() to cast the struct perf_event cpu field to an unsigned integer before it is compared with nr_cpumask_bits (and *ahem* did so without copying the linux-mips mailing list or any MIPS developers...). This is broken because the cpu field may be -1 for events which follow a process rather than being affine to a particular CPU. When this is the case the cast to an unsigned int results in a value equal to ULONG_MAX, which is always greater than nr_cpumask_bits so we always fail mipspmu_event_init() and return -ENODEV. The check against nr_cpumask_bits seems nonsensical anyway, so this patch simply removes it. The cpu field is going to either be -1 or a valid CPU number. Comparing it with nr_cpumask_bits is effectively checking that it's a valid cpu number, but it seems safe to rely on the core perf events code to ensure that's the case. The end result is that this fixes use of perf on MIPS when not constraining events to a particular CPU, and fixes the "perf list hw" command which fails to list any events without this. Signed-off-by: Paul Burton Fixes: c311c797998c ("cpumask: make "nr_cpumask_bits" unsigned") Cc: Alexey Dobriyan Cc: Andrew Morton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17323/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Remove pt_regs adjustments in indirect syscall handler

2017-08-29T13:48:34+00:00

If a restartable syscall is called using the indirect o32 syscall handler - eg: syscall(__NR_waitid, ...), then it is possible for the incorrect arguments to be passed to the syscall after it has been restarted. This is because the syscall handler tries to shift all the registers down one place in pt_regs so that when the syscall is restarted, the "real" syscall is called instead. Unfortunately it only shifts the arguments passed in registers, not the arguments on the user stack. This causes the 4th argument to be duplicated when the syscall is restarted. Fix by removing all the pt_regs shifting so that the indirect syscall handler is called again when the syscall is restarted. The comment "some syscalls like execve get their arguments from struct pt_regs" is long out of date so this should now be safe. Signed-off-by: James Cowgill Reviewed-by: James Hogan Tested-by: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/15856/ Signed-off-by: Ralf Baechle

MIPS: seccomp: Fix indirect syscall args

2017-08-29T13:42:44+00:00

Since commit 669c4092225f ("MIPS: Give __secure_computing() access to syscall arguments."), upon syscall entry when seccomp is enabled, syscall_trace_enter() passes a carefully prepared struct seccomp_data containing syscall arguments to __secure_computing(). Unfortunately it directly uses mips_get_syscall_arg() and fails to take into account the indirect O32 system calls (i.e. syscall(2)) which put the system call number in a0 and have the arguments shifted up by one entry. We can't just revert that commit as samples/bpf/tracex5 would break again, so use syscall_get_arguments() which already takes indirect syscalls into account instead of directly using mips_get_syscall_arg(), similar to what populate_seccomp_data() does. This also removes the redundant error checking of the mips_get_syscall_arg() return value (get_user() already zeroes the result if an argument from the stack can't be loaded). Reported-by: James Cowgill Fixes: 669c4092225f ("MIPS: Give __secure_computing() access to syscall arguments.") Signed-off-by: James Hogan Reviewed-by: Kees Cook Cc: David Daney Cc: Andy Lutomirski Cc: Will Drewry Cc: Oleg Nesterov Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16994/ Signed-off-by: Ralf Baechle

MIPS: Fix race on setting and getting cpu_online_mask

2017-08-07T09:57:30+00:00

While testing cpu hoptlug (cpu down and up in loops) on kernel 4.4, it was observed that occasionally check for cpu online will fail in kernel/cpu.c, _cpu_up: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/kernel/cpu.c?h=v4.4.79#n485 518 /* Arch-specific enabling code. */ 519 ret = __cpu_up(cpu, idle); 520 521 if (ret != 0) 522 goto out_notify; 523 BUG_ON(!cpu_online(cpu)); Reason is race between start_secondary and _cpu_up. cpu_callin_map is set before cpu_online_mask. In __cpu_up, cpu_callin_map is waited for, but cpu online mask is not, resulting in race in which secondary processor started and set cpu_callin_map, but not yet set the online mask,resulting in above BUG being hit. Upstream differs in the area. cpu_online check is in bringup_wait_for_ap, which is after cpu reached AP_ONLINE_IDLE,where secondary passed its start function. Nonetheless, fix makes start_secondary safe and not depending on other locks throughout the code. It protects as well against cpu_online checks put in between sometimes in the future. Fix this by moving completion after all flags are set. Signed-off-by: Matija Glavinic Pecotic Cc: Alexander Sverdlin Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16925/ Signed-off-by: Ralf Baechle

Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

2017-07-15T17:59:54+00:00

Pull MIPS updates from Ralf Baechle: "Boston platform support: - Document DT bindings - Add CLK driver for board clocks CM: - Avoid per-core locking with CM3 & higher - WARN on attempt to lock invalid VP, not BUG CPS: - Select CONFIG_SYS_SUPPORTS_SCHED_SMT for MIPSr6 - Prevent multi-core with dcache aliasing - Handle cores not powering down more gracefully - Handle spurious VP starts more gracefully DSP: - Add lwx & lhx missaligned access support eBPF: - Add MIPS support along with many supporting change to add the required infrastructure Generic arch code: - Misc sysmips MIPS_ATOMIC_SET fixes - Drop duplicate HAVE_SYSCALL_TRACEPOINTS - Negate error syscall return in trace - Correct forced syscall errors - Traced negative syscalls should return -ENOSYS - Allow samples/bpf/tracex5 to access syscall arguments for sane traces - Cleanup from old Kconfig options in defconfigs - Fix PREF instruction usage by memcpy for MIPS R6 - Fix various special cases in the FPU eulation - Fix some special cases in MIPS16e2 support - Fix MIPS I ISA /proc/cpuinfo reporting - Sort MIPS Kconfig alphabetically - Fix minimum alignment requirement of IRQ stack as required by ABI / GCC - Fix special cases in the module loader - Perform post-DMA cache flushes on systems with MAARs - Probe the I6500 CPU - Cleanup cmpxchg and add support for 1 and 2 byte operations - Use queued read/write locks (qrwlock) - Use queued spinlocks (qspinlock) - Add CPU shared FTLB feature detection - Handle tlbex-tlbp race condition - Allow storing pgd in C0_CONTEXT for MIPSr6 - Use current_cpu_type() in m4kc_tlbp_war() - Support Boston in the generic kernel Generic platform: - yamon-dt: Pull YAMON DT shim code out of SEAD-3 board - yamon-dt: Support > 256MB of RAM - yamon-dt: Use serial* rather than uart* aliases - Abstract FDT fixup application - Set RTC_ALWAYS_BCD to 0 - Add a MAINTAINERS entry core kernel: - qspinlock.c: include linux/prefetch.h Loongson 3: - Add support Perf: - Add I6500 support SEAD-3: - Remove GIC timer from DT - Set interrupt-parent per-device, not at root node - Fix GIC interrupt specifiers SMP: - Skip IPI setup if we only have a single CPU VDSO: - Make comment match reality - Improvements to time code in VDSO" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (86 commits) locking/qspinlock: Include linux/prefetch.h MIPS: Fix MIPS I ISA /proc/cpuinfo reporting MIPS: Fix minimum alignment requirement of IRQ stack MIPS: generic: Support MIPS Boston development boards MIPS: DTS: img: Don't attempt to build-in all .dtb files clk: boston: Add a driver for MIPS Boston board clocks dt-bindings: Document img,boston-clock binding MIPS: Traced negative syscalls should return -ENOSYS MIPS: Correct forced syscall errors MIPS: Negate error syscall return in trace MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select MIPS16e2: Provide feature overrides for non-MIPS16 systems MIPS: MIPS16e2: Report ASE presence in /proc/cpuinfo MIPS: MIPS16e2: Subdecode extended LWSP/SWSP instructions MIPS: MIPS16e2: Identify ASE presence MIPS: VDSO: Fix a mismatch between comment and preprocessor constant MIPS: VDSO: Add implementation of gettimeofday() fallback MIPS: VDSO: Add implementation of clock_gettime() fallback MIPS: VDSO: Fix conversions in do_monotonic()/do_monotonic_coarse() MIPS: Use current_cpu_type() in m4kc_tlbp_war() ...

MIPS: Fix MIPS I ISA /proc/cpuinfo reporting

2017-07-11T12:13:50+00:00

Correct a commit 515a6393dbac ("MIPS: kernel: proc: Add MIPS R6 support to /proc/cpuinfo") regression that caused MIPS I systems to show no ISA levels supported in /proc/cpuinfo, e.g.: system type : Digital DECstation 2100/3100 machine : Unknown processor : 0 cpu model : R3000 V2.0 FPU V2.0 BogoMIPS : 10.69 wait instruction : no microsecond timers : no tlb_entries : 64 extra interrupt vector : no hardware watchpoint : no isa : ASEs implemented : shadow register sets : 1 kscratch registers : 0 package : 0 core : 0 VCED exceptions : not available VCEI exceptions : not available and similarly exclude `mips1' from the ISA list for any processors below MIPSr1. This is because the condition to show `mips1' on has been made `cpu_has_mips_r1' rather than newly-introduced `cpu_has_mips_1'. Use the correct condition then. Fixes: 515a6393dbac ("MIPS: kernel: proc: Add MIPS R6 support to /proc/cpuinfo") Signed-off-by: Maciej W. Rozycki Reviewed-by: James Hogan Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.19+ Patchwork: https://patchwork.linux-mips.org/patch/16758/ Signed-off-by: Ralf Baechle

MIPS: Traced negative syscalls should return -ENOSYS

2017-07-11T12:13:06+00:00

If a negative system call number is used when system call tracing is enabled, syscall_trace_enter() will return that negative system call number without having written the return value and error flag into the pt_regs. The caller then treats it as a cancelled system call and assumes that the return value and error flag are already written, leaving the negative system call number in the return register ($v0), and the 4th system call argument in the error register ($a3). Add a special case to detect this at the end of syscall_trace_enter(), to set the return value to error -ENOSYS when this happens. Fixes: d218af78492a ("MIPS: scall: Always run the seccomp syscall filters") Signed-off-by: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16653/ Signed-off-by: Ralf Baechle