user/sven/linux.git/arch, branch v3.4.46

powerpc: Bring all threads online prior to migration/hibernation

2013-05-19T17:54:40Z

commit 120496ac2d2d60aee68d3123a68169502a85f4b5 upstream. This patch brings online all threads which are present but not online prior to migration/hibernation. After migration/hibernation those threads are taken back offline. During migration/hibernation all online CPUs must call H_JOIN, this is required by the hypervisor. Without this patch, threads that are offline (H_CEDE'd) will not be woken to make the H_JOIN call and the OS will be deadlocked (all threads either JOIN'd or CEDE'd). Signed-off-by: Robert Jennings Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.

2013-05-19T17:54:38Z

commit 7f1fc268c47491fd5e63548f6415fc8604e13003 upstream. If a user did: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online we would (this a build with DEBUG enabled) get to: smpboot: ++++++++++++++++++++=_---CPU UP 1 .. snip.. smpboot: Stack at about ffff880074c0ff44 smpboot: CPU1: has booted. and hang. The RCU mechanism would kick in an try to IPI the CPU1 but the IPIs (and all other interrupts) would never arrive at the CPU1. At first glance at least. A bit digging in the hypervisor trace shows that (using xenanalyze): [vla] d4v1 vec 243 injecting 0.043163027 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043163639 --|x d4v1 vmentry cycles 1468 ] 0.043164913 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043164913 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting 0.043164913 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043165526 --|x d4v1 vmentry cycles 1472 ] 0.043166800 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043166800 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting there is a pending event (subsequent debugging shows it is the IPI from the VCPU0 when smpboot.c on VCPU1 has done "set_cpu_online(smp_processor_id(), true)") and the guest VCPU1 is interrupted with the callback IPI (0xf3 aka 243) which ends up calling __xen_evtchn_do_upcall. The __xen_evtchn_do_upcall seems to do *something* but not acknowledge the pending events. And the moment the guest does a 'cli' (that is the ffffffff81673254 in the log above) the hypervisor is invoked again to inject the IPI (0xf3) to tell the guest it has pending interrupts. This repeats itself forever. The culprit was the per_cpu(xen_vcpu, cpu) pointer. At the bootup we set each per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] but later on use the VCPUOP_register_vcpu_info to register per-CPU structures (xen_vcpu_setup). This is used to allow events for more than 32 VCPUs and for performance optimizations reasons. When the user performs the VCPU hotplug we end up calling the the xen_vcpu_setup once more. We make the hypercall which returns -EINVAL as it does not allow multiple registration calls (and already has re-assigned where the events are being set). We pick the fallback case and set per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] (which is a good fallback during bootup). However the hypervisor is still setting events in the register per-cpu structure (per_cpu(xen_vcpu_info, cpu)). As such when the events are set by the hypervisor (such as timer one), and when we iterate in __xen_evtchn_do_upcall we end up reading stale events from the shared_info->vcpu_info[vcpu] instead of the per_cpu(xen_vcpu_info, cpu) structures. Hence we never acknowledge the events that the hypervisor has set and the hypervisor keeps on reminding us to ack the events which we never do. The fix is simple. Don't on the second time when xen_vcpu_setup is called over-write the per_cpu(xen_vcpu, cpu) if it points to per_cpu(xen_vcpu_info). Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman

ARM: OMAP: RX-51: change probe order of touchscreen and panel SPI devices

2013-05-19T17:54:34Z

commit e65f131a14726e5f1b880a528271a52428e5b3a5 upstream. Commit 9fdca9df (spi: omap2-mcspi: convert to module_platform_driver) broke the SPI display/panel driver probe on RX-51/N900. The exact cause is not fully understood, but it seems to be related to the probe order. SPI communication to the panel driver (spi1.2) fails unless the touchscreen (spi1.0) has been probed/initialized before. When the omap2-mcspi driver was converted to a platform driver, it resulted in that the devices are probed immediately after the board registers them in the order they are listed in the board file. Fix the issue by moving the touchscreen before the panel in the SPI device list. The patch fixes the following failure: [ 1.260955] acx565akm spi1.2: invalid display ID [ 1.265899] panel-acx565akm display0: acx_panel_probe panel detect error [ 1.273071] omapdss CORE error: driver probe failed: -19 Tested-by: Sebastian Reichel Signed-off-by: Aaro Koskinen Cc: Pali Rohár Cc: Joni Lapilainen Cc: Tomi Valkeinen Cc: Felipe Balbi Signed-off-by: Tony Lindgren Signed-off-by: Greg Kroah-Hartman

KVM: VMX: fix halt emulation while emulating invalid guest sate

2013-05-19T17:54:34Z

commit 8d76c49e9ffeee839bc0b7a3278a23f99101263e upstream. The invalid guest state emulation loop does not check halt_request which causes 100% cpu loop while guest is in halt and in invalid state, but more serious issue is that this leaves halt_request set, so random instruction emulated by vm86 #GP exit can be interpreted as halt which causes guest hang. Fix both problems by handling halt_request in emulation loop. Reported-by: Tomas Papan Tested-by: Tomas Papan Reviewed-by: Paolo Bonzini Signed-off-by: Gleb Natapov Signed-off-by: Greg Kroah-Hartman

x86/mm: account for PGDIR_SIZE alignment

2013-05-11T20:48:15Z

Patch for -stable. Function find_early_table_space removed upstream. Fixes panic in alloc_low_page due to pgt_buf overflow during init_memory_mapping. find_early_table_space sizes pgt_buf based upon the size of the memory being mapped, but it does not take into account the alignment of the memory. When the region being mapped spans a 512GB (PGDIR_SIZE) alignment, a panic from alloc_low_pages occurs. kernel_physical_mapping_init takes into account PGDIR_SIZE alignment. This causes an extra call to alloc_low_page to be made. This extra call isn't accounted for by find_early_table_space and causes a kernel panic. Change is to take into account PGDIR_SIZE alignment in find_early_table_space. Signed-off-by: Jerry Hoemann Signed-off-by: Greg Kroah-Hartman

perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL

2013-05-11T20:48:07Z

commit 7cc23cd6c0c7d7f4bee057607e7ce01568925717 upstream. We should always have proper privileges when requesting kernel data. Signed-off-by: Peter Zijlstra Cc: Andi Kleen Cc: eranian@google.com Link: http://lkml.kernel.org/r/20130503121256.230745028@chello.nl [ Fix build error reported by fengguang.wu@intel.com, propagate error code back. ] Signed-off-by: Ingo Molnar Link: http://lkml.kernel.org/n/tip-v0x9ky3ahzr6nm3c6ilwrili@git.kernel.org Signed-off-by: Greg Kroah-Hartman

perf/x86/intel/lbr: Fix LBR filter

2013-05-11T20:48:07Z

commit 6e15eb3ba6c0249c9e8c783517d131b47db995ca upstream. The LBR 'from' adddress is under full userspace control; ensure we validate it before reading from it. Note: is_module_text_address() can potentially be quite expensive; for those running into that with high overhead in modules optimize it using an RCU backed rb-tree. Reported-by: Andi Kleen Signed-off-by: Peter Zijlstra Cc: eranian@google.com Link: http://lkml.kernel.org/r/20130503121256.158211806@chello.nl Signed-off-by: Ingo Molnar Link: http://lkml.kernel.org/n/tip-mk8i82ffzax01cnqo829iy1q@git.kernel.org Signed-off-by: Greg Kroah-Hartman

powerpc: fix numa distance for form0 device tree

2013-05-11T20:48:06Z

commit 7122beeee7bc1757682049780179d7c216dd1c83 upstream. The following commit breaks numa distance setup for old powerpc systems that use form0 encoding in device tree. commit 41eab6f88f24124df89e38067b3766b7bef06ddb powerpc/numa: Use form 1 affinity to setup node distance Device tree node /rtas/ibm,associativity-reference-points would index into /cpus/PowerPCxxxx/ibm,associativity based on form0 or form1 encoding detected by ibm,architecture-vec-5 property. All modern systems use form1 and current kernel code is correct. However, on older systems with form0 encoding, the numa distance will get hard coded as LOCAL_DISTANCE for all nodes. This causes task scheduling anomaly since scheduler will skip building numa level domain (topmost domain with all cpus) if all numa distances are same. (value of 'level' in sched_init_numa() will remain 0) Prior to the above commit: ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE) Restoring compatible behavior with this patch for old powerpc systems with device tree where numa distance are encoded as form0. Signed-off-by: Vaidyanathan Srinivasan Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc: Emulate non privileged DSCR read and write

2013-05-11T20:48:05Z

commit 73d2fb758e678c93bc76d40876c2359f0729b0ef upstream. POWER8 allows read and write of the DSCR in userspace. We added kernel emulation so applications could always use the instructions regardless of the CPU type. Unfortunately there are two SPRs for the DSCR and we only added emulation for the privileged one. Add code to match the non privileged one. A simple test was created to verify the fix: http://ozlabs.org/~anton/junkcode/user_dscr_test.c Without the patch we get a SIGILL and it passes with the patch. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

x86: Eliminate irq_mis_count counted in arch_irq_stat

2013-05-08T02:51:57Z

commit f7b0e1055574ce06ab53391263b4e205bf38daf3 upstream. With the current implementation, kstat_cpu(cpu).irqs_sum is also increased in case of irq_mis_count increment. So there is no need to count irq_mis_count in arch_irq_stat, otherwise irq_mis_count will be counted twice in the sum of /proc/stat. Reported-by: Liu Chuansheng Signed-off-by: Li Fei Acked-by: Liu Chuansheng Cc: tomoki.sekiyama.qu@hitachi.com Cc: joe@perches.com Link: http://lkml.kernel.org/r/1366980611.32469.7.camel@fli24-HP-Compaq-8100-Elite-CMT-PC Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman