talos-obmc-linux/arch/arm/kernel, branch v3.6-rc3

ARM: 7486/1: sched_clock: update epoch_cyc on resume

2012-08-11T08:15:58+00:00

Many clocks that are used to provide sched_clock will reset during suspend. If read_sched_clock returns 0 after suspend, sched_clock will appear to jump forward. This patch resets cd.epoch_cyc to the current value of read_sched_clock during resume, which causes sched_clock() just after suspend to return the same value as sched_clock() just before suspend. In addition, during the window where epoch_ns has been updated before suspend, but epoch_cyc has not been updated after suspend, it is unknown whether the clock has reset or not, and sched_clock() could return a bogus value. Add a suspended flag, and return the pre-suspend epoch_ns value during this period. The new behavior is triggered by calling setup_sched_clock_needs_suspend instead of setup_sched_clock. Signed-off-by: Colin Cross Reviewed-by: Linus Walleij Signed-off-by: Russell King

ARM: 7482/1: topology: fix section mismatch warning for init_cpu_topology

2012-08-11T08:15:56+00:00

Get rid of this warning.. arch/arm/kernel/built-in.o(.text+0xac78): Section mismatch in reference from the function init_cpu_topology() to the function .init.text:parse_dt_topology() The function init_cpu_topology() references the function __init parse_dt_topology(). This is often because init_cpu_topology lacks a __init annotation or the annotation of parse_dt_topology is wrong. Signed-off-by: Venkatraman S Signed-off-by: Russell King

Merge branch 'audit' of git://git.linaro.org/people/rmk/linux-arm

2012-08-01T23:35:37+00:00

Pull ARM audit/signal updates from Russell King: "ARM audit/signal handling updates from Al and Will. This improves on the work Viro did last merge window, and sorts out some of the issues found with that work." * 'audit' of git://git.linaro.org/people/rmk/linux-arm: ARM: 7475/1: sys_trace: allow all syscall arguments to be updated via ptrace ARM: 7474/1: get rid of TIF_SYSCALL_RESTARTSYS ARM: 7473/1: deal with handlerless restarts without leaving the kernel ARM: 7472/1: pull all work_pending logics into C function ARM: 7471/1: Revert "7442/1: Revert "remove unused restart trampoline"" ARM: 7470/1: Revert "7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK""

Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm

2012-08-01T23:30:45+00:00

Pull ARM fixes from Russell King: "This fixes various issues found during July" * 'fixes' of git://git.linaro.org/people/rmk/linux-arm: ARM: 7479/1: mm: avoid NULL dereference when flushing gate_vma with VIVT caches ARM: Fix undefined instruction exception handling ARM: 7480/1: only call smp_send_stop() on SMP ARM: 7478/1: errata: extend workaround for erratum #720789 ARM: 7477/1: vfp: Always save VFP state in vfp_pm_suspend on UP ARM: 7476/1: vfp: only clear vfp state for current cpu in vfp_pm_suspend ARM: 7468/1: ftrace: Trace function entry before updating index ARM: 7467/1: mutex: use generic xchg-based implementation for ARMv6+ ARM: 7466/1: disable interrupt before spinning endlessly ARM: 7465/1: Handle >4GB memory sizes in device tree and mem=size@start option

ARM: Fix undefined instruction exception handling

2012-07-31T11:04:30+00:00

While trying to get a v3.5 kernel booted on the cubox, I noticed that VFP does not work correctly with VFP bounce handling. This is because of the confusion over 16-bit vs 32-bit instructions, and where PC is supposed to point to. The rule is that FP handlers are entered with regs->ARM_pc pointing at the _next_ instruction to be executed. However, if the exception is not handled, regs->ARM_pc points at the faulting instruction. This is easy for ARM mode, because we know that the next instruction and previous instructions are separated by four bytes. This is not true of Thumb2 though. Since all FP instructions are 32-bit in Thumb2, it makes things easy. We just need to select the appropriate adjustment. Do this by moving the adjustment out of do_undefinstr() into the assembly code, as only the assembly code knows whether it's dealing with a 32-bit or 16-bit instruction. Cc: Acked-by: Will Deacon Signed-off-by: Russell King

ARM: 7480/1: only call smp_send_stop() on SMP

2012-07-31T09:30:44+00:00

On reboot or poweroff (machine_shutdown()) a call to smp_send_stop() is made (to stop the others CPU's) when CONFIG_SMP=y. arch/arm/kernel/process.c: void machine_shutdown(void) { #ifdef CONFIG_SMP smp_send_stop(); #endif } smp_send_stop() calls the function pointer smp_cross_call(), which is set on the smp_init_cpus() function for OMAP processors. arch/arm/mach-omap2/omap-smp.c: void __init smp_init_cpus(void) { ... set_smp_cross_call(gic_raise_softirq); ... } But the ARM setup_arch() function only calls smp_init_cpus() if CONFIG_SMP=y && is_smp(). arm/kernel/setup.c: void __init setup_arch(char **cmdline_p) { ... #ifdef CONFIG_SMP if (is_smp()) smp_init_cpus(); #endif ... } Newer OMAP CPU's are SMP machines so omap2plus_defconfig sets CONFIG_SMP=y. Unfortunately on an OMAP UP machine is_smp() returns false and smp_init_cpus() is never called and the smp_cross_call() function remains NULL. If the machine is rebooted or powered off, smp_send_stop() will be called (since CONFIG_SMP=y) leading to the following error: [ 42.815551] Restarting system. [ 42.819030] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 42.827667] pgd = d7a74000 [ 42.830566] [00000000] *pgd=96ce7831, *pte=00000000, *ppte=00000000 [ 42.837249] Internal error: Oops: 80000007 [#1] SMP ARM [ 42.842773] Modules linked in: [ 42.846008] CPU: 0 Not tainted (3.5.0-rc3-next-20120622-00002-g62e87ba-dirty #44) [ 42.854278] PC is at 0x0 [ 42.856994] LR is at smp_send_stop+0x4c/0xe4 [ 42.861511] pc : [<00000000>] lr : [] psr: 60000013 [ 42.861511] sp : d6c85e70 ip : 00000000 fp : 00000000 [ 42.873626] r10: 00000000 r9 : d6c84000 r8 : 00000002 [ 42.879150] r7 : c07235a0 r6 : c06dd2d0 r5 : 000f4241 r4 : d6c85e74 [ 42.886047] r3 : 00000000 r2 : 00000000 r1 : 00000006 r0 : d6c85e74 [ 42.892944] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 42.900482] Control: 10c5387d Table: 97a74019 DAC: 00000015 [ 42.906555] Process reboot (pid: 1166, stack limit = 0xd6c842f8) [ 42.912902] Stack: (0xd6c85e70 to 0xd6c86000) [ 42.917510] 5e60: c07235a0 00000000 00000000 d6c84000 [ 42.926177] 5e80: 01234567 c00143d0 4321fedc c00511bc d6c85ebc 00000168 00000460 00000000 [ 42.934814] 5ea0: c1017950 a0000013 c1017900 d8014390 d7ec3858 c0498e48 c1017950 00000000 [ 42.943481] 5ec0: d6ddde10 d6c85f78 00000003 00000000 d6ddde10 d6c84000 00000000 00000000 [ 42.952117] 5ee0: 00000002 00000000 00000000 c0088c88 00000002 00000000 00000000 c00f4b90 [ 42.960784] 5f00: 00000000 d6c85ebc d8014390 d7e311c8 60000013 00000103 00000002 d6c84000 [ 42.969421] 5f20: c00f3274 d6e00a00 00000001 60000013 d6c84000 00000000 00000000 c00895d4 [ 42.978057] 5f40: 00000002 d8007c80 d781f000 c00f6150 d8010cc0 c00f3274 d781f000 d6c84000 [ 42.986694] 5f60: c0013020 d6e00a00 00000001 20000010 0001257c ef000000 00000000 c00895d4 [ 42.995361] 5f80: 00000002 00000001 00000003 00000000 00000001 00000003 00000000 00000058 [ 43.003997] 5fa0: c00130c8 c0012f00 00000001 00000003 fee1dead 28121969 01234567 00000002 [ 43.012634] 5fc0: 00000001 00000003 00000000 00000058 00012584 0001257c 00000001 00000000 [ 43.021270] 5fe0: 000124bc bec5cc6c 00008f9c 4a2f7c40 20000010 fee1dead 00000000 00000000 [ 43.029968] [] (smp_send_stop+0x4c/0xe4) from [] (machine_restart+0xc/0x4c) [ 43.039154] [] (machine_restart+0xc/0x4c) from [] (sys_reboot+0x144/0x1f0) [ 43.048278] [] (sys_reboot+0x144/0x1f0) from [] (ret_fast_syscall+0x0/0x3c) [ 43.057464] Code: bad PC value [ 43.060760] ---[ end trace c3988d1dd0b8f0fb ]--- Add a check so smp_cross_call() is only called when there is more than one CPU on-line. Cc: Signed-off-by: Javier Martinez Canillas Acked-by: Will Deacon Signed-off-by: Russell King

ARM: 7468/1: ftrace: Trace function entry before updating index

2012-07-31T09:30:42+00:00

Commit 722b3c74695377d11d18a52f3da08114d37f3f37 modified x86 ftrace to avoid tracing all functions called from irqs when function graph was used with a filter. Port the same fix to ARM. Acked-by: Steven Rostedt Signed-off-by: Colin Cross Signed-off-by: Russell King

ARM: 7466/1: disable interrupt before spinning endlessly

2012-07-31T09:30:31+00:00

The CPU will endlessly spin at the end of machine_halt and machine_restart calls. However, this will lead to a soft lockup warning after about 20 seconds, if CONFIG_LOCKUP_DETECTOR is enabled, as system timer is still alive. Disable interrupt before going to spin endlessly, so that the lockup warning will never be seen. Cc: Reported-by: Marek Vasut Signed-off-by: Shawn Guo Signed-off-by: Russell King

ARM: 7465/1: Handle >4GB memory sizes in device tree and mem=size@start option

2012-07-29T21:19:14+00:00

The memory regions which are passed to arm_add_memory() from device tree blobs via early_init_dt_add_memory_arch() can have sizes which are larger than will fit in a 32 bit integer, so switch to using a phys_addr_t to hold them, to avoid silently dropping the top 32 bits of the size. Similarly, use phys_addr_t in early_mem() so that mem=size@start command line options specifying more than 4GB behave sensibly. Acked-by: Will Deacon Signed-off-by: Peter Maydell Signed-off-by: Russell King

ARM: 7475/1: sys_trace: allow all syscall arguments to be updated via ptrace

2012-07-28T10:11:53+00:00

Prior to syscall invocation, __sys_trace only reloads r0-r3 from the kernel stack, preventing the debugger from updating arguments 5-7 when signalled via ptrace. This patch updates the code to reload r0-r6, updating arguments 5 and 6 on the stack (argument 7 is only used by OABI indirect syscalls and can remain in a register). Reported-by: Al Viro Signed-off-by: Will Deacon Signed-off-by: Russell King