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* powerpc/pseries: Fix regression on PCI link speedKleber Sacilotto de Souza2014-02-171-7/+9
| | | | | | | | | | | | | | | | | Commit 5091f0c (powerpc/pseries: Fix PCIE link speed endian issue) introduced a regression on the PCI link speed detection using the device-tree property. The ibm,pcie-link-speed-stats property is composed of two 32-bit integers, the first one being the maxinum link speed and the second the current link speed. The changes introduced by the aforementioned commit are considering just the first integer. Fix this issue by changing how the property is accessed, using the helper functions to properly access the array of values. The explicit byte swapping is not needed anymore here, since it's done by the helper functions. Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Set the correct ksp_limit on ppc32 when switching to irq stackKevin Hao2014-02-171-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Guenter Roeck has got the following call trace on a p2020 board: Kernel stack overflow in process eb3e5a00, r1=eb79df90 CPU: 0 PID: 2838 Comm: ssh Not tainted 3.13.0-rc8-juniper-00146-g19eca00 #4 task: eb3e5a00 ti: c0616000 task.ti: ef440000 NIP: c003a420 LR: c003a410 CTR: c0017518 REGS: eb79dee0 TRAP: 0901 Not tainted (3.13.0-rc8-juniper-00146-g19eca00) MSR: 00029000 <CE,EE,ME> CR: 24008444 XER: 00000000 GPR00: c003a410 eb79df90 eb3e5a00 00000000 eb05d900 00000001 65d87646 00000000 GPR08: 00000000 020b8000 00000000 00000000 44008442 NIP [c003a420] __do_softirq+0x94/0x1ec LR [c003a410] __do_softirq+0x84/0x1ec Call Trace: [eb79df90] [c003a410] __do_softirq+0x84/0x1ec (unreliable) [eb79dfe0] [c003a970] irq_exit+0xbc/0xc8 [eb79dff0] [c000cc1c] call_do_irq+0x24/0x3c [ef441f20] [c00046a8] do_IRQ+0x8c/0xf8 [ef441f40] [c000e7f4] ret_from_except+0x0/0x18 --- Exception: 501 at 0xfcda524 LR = 0x10024900 Instruction dump: 7c781b78 3b40000a 3a73b040 543c0024 3a800000 3b3913a0 7ef5bb78 48201bf9 5463103a 7d3b182e 7e89b92e 7c008146 <3ba00000> 7e7e9b78 48000014 57fff87f Kernel panic - not syncing: kernel stack overflow CPU: 0 PID: 2838 Comm: ssh Not tainted 3.13.0-rc8-juniper-00146-g19eca00 #4 Call Trace: The reason is that we have used the wrong register to calculate the ksp_limit in commit cbc9565ee826 (powerpc: Remove ksp_limit on ppc64). Just fix it. As suggested by Benjamin Herrenschmidt, also add the C prototype of the function in the comment in order to avoid such kind of errors in the future. Cc: stable@vger.kernel.org # 3.12 Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/powernv: Add iommu DMA bypass support for IODA2Benjamin Herrenschmidt2014-02-119-4/+137
| | | | | | | | | | | | | | | This patch adds the support for to create a direct iommu "bypass" window on IODA2 bridges (such as Power8) allowing to bypass iommu page translation completely for 64-bit DMA capable devices, thus significantly improving DMA performances. Additionally, this adds a hook to the struct iommu_table so that the IOMMU API / VFIO can disable the bypass when external ownership is requested, since in that case, the device will be used by an environment such as userspace or a KVM guest which must not be allowed to bypass translations. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Fix endian issues in kexec and crash dump codeAnton Blanchard2014-02-112-6/+14
| | | | | | | | | We expose a number of OF properties in the kexec and crash dump code and these need to be big endian. Cc: stable@vger.kernel.org # v3.13 Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/ppc32: Fix the bug in the init of non-base exception stack for UPKevin Hao2014-02-112-0/+10
| | | | | | | | | | | | | We would allocate one specific exception stack for each kind of non-base exceptions for every CPU. For ppc32 the CPU hard ID is used as the subscript to get the specific exception stack for one CPU. But for an UP kernel, there is only one element in the each kind of exception stack array. We would get stuck if the CPU hard ID is not equal to '0'. So in this case we should use the subscript '0' no matter what the CPU hard ID is. Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/xmon: Don't signal we've entered until we're finished printingMichael Ellerman2014-02-111-1/+2
| | | | | | | | | | | | | | | Currently we set our cpu's bit in cpus_in_xmon, and then we take the output lock and print the exception information. This can race with the master cpu entering the command loop and printing the backtrace. The result is that the backtrace gets garbled with another cpu's exception print out. Fix it by delaying the set of cpus_in_xmon until we are finished printing. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/xmon: Fix timeout loop in get_output_lock()Michael Ellerman2014-02-111-2/+9
| | | | | | | | | | | | | | | | | | | | As far as I can tell, our 70s era timeout loop in get_output_lock() is generating no code. This leads to the hostile takeover happening more or less simultaneously on all cpus. The result is "interesting", some example output that is more readable than most: cpu 0x1: Vector: 100 (Scypsut e0mx bR:e setV)e catto xc0p:u[ c 00 c0:0 000t0o0V0erc0td:o5 rfc28050000]0c00 0 0 0 6t(pSrycsV1ppuot uxe 1m 2 0Rx21e3:0s0ce000c00000t00)00 60602oV2SerucSayt0y 0p 1sxs Fix it by using udelay() in the timeout loop. The wait time and check frequency are arbitrary, but seem to work OK. We already rely on udelay() working so this is not a new dependency. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/xmon: Don't loop forever in get_output_lock()Michael Ellerman2014-02-111-5/+5
| | | | | | | | | | | | | | | | | | | | | If we enter with xmon_speaker != 0 we skip the first cmpxchg(), we also skip the while loop because xmon_speaker != last_speaker (0) - meaning we skip the second cmpxchg() also. Following that code path the compiler sees no memory barriers and so is within its rights to never reload xmon_speaker. The end result is we loop forever. This manifests as all cpus being in xmon ('c' command), but they refuse to take control when you switch to them ('c x' for cpu # x). I have seen this deadlock in practice and also checked the generated code to confirm this is what's happening. The simplest fix is just to always try the cmpxchg(). Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/perf: Configure BHRB filter before enabling PMU interruptsAnshuman Khandual2014-02-111-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Right now the config_bhrb() PMU specific call happens after write_mmcr0(), which actually enables the PMU for event counting and interrupts. So there is a small window of time where the PMU and BHRB runs without the required HW branch filter (if any) enabled in BHRB. This can cause some of the branch samples to be collected through BHRB without any filter applied and hence affects the correctness of the results. This patch moves the BHRB config function call before enabling interrupts. Here are some data points captured via trace prints which depicts how we could get PMU interrupts with BHRB filter NOT enabled with a standard perf record command line (asking for branch record information as well). $ perf record -j any_call ls Before the patch:- ls-1962 [003] d... 2065.299590: .perf_event_interrupt: MMCRA: 40000000000 ls-1962 [003] d... 2065.299603: .perf_event_interrupt: MMCRA: 40000000000 ... All the PMU interrupts before this point did not have the requested HW branch filter enabled in the MMCRA. ls-1962 [003] d... 2065.299647: .perf_event_interrupt: MMCRA: 40040000000 ls-1962 [003] d... 2065.299662: .perf_event_interrupt: MMCRA: 40040000000 After the patch:- ls-1850 [008] d... 190.311828: .perf_event_interrupt: MMCRA: 40040000000 ls-1850 [008] d... 190.311848: .perf_event_interrupt: MMCRA: 40040000000 All the PMU interrupts have the requested HW BHRB branch filter enabled in MMCRA. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> [mpe: Fixed up whitespace and cleaned up changelog] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/pseries: Select ARCH_RANDOM on pseriesMichael Ellerman2014-02-111-0/+1
| | | | | | | | | | | | | We have a driver for the ARCH_RANDOM hook in rng.c, so we should select ARCH_RANDOM on pseries. Without this the build breaks if you turn ARCH_RANDOM off. This hasn't broken the build because pseries_defconfig doesn't specify a value for PPC_POWERNV, which is default y, and selects ARCH_RANDOM. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/perf: Add Power8 cache & TLB eventsMichael Ellerman2014-02-111-0/+144
| | | | | Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/relocate fix relocate processing in LE modeLaurent Dufour2014-02-111-2/+2
| | | | | | | | | | | | | | | | Relocation's code is not working in little endian mode because the r_info field, which is a 64 bits value, should be read from the right offset. The current code is optimized to read the r_info field as a 32 bits value starting at the middle of the double word (offset 12). When running in LE mode, the read value is not correct since only the MSB is read. This patch removes this optimization which consist to deal with a 32 bits value instead of a 64 bits one. This way it works in big and little endian mode. Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Fix kdump hang issue on p8 with relocation on exception enabled.Mahesh Salgaonkar2014-02-112-0/+26
| | | | | | | | | | | | | | | | | | | | | On p8 systems, with relocation on exception feature enabled we are seeing kdump kernel hang at interrupt vector 0xc*4400. The reason is, with this feature enabled, exception are raised with MMU (IR=DR=1) ON with the default offset of 0xc*4000. Since exception is raised in virtual mode it requires the vector region to be executable without which it fails to fetch and execute instruction at 0xc*4xxx. For default kernel since kernel is loaded at real 0, the htab mappings sets the entire kernel text region executable. But for relocatable kernel (e.g. kdump case) we only copy interrupt vectors down to real 0 and never marked that region as executable because in p7 and below we always get exception in real mode. This patch fixes this issue by marking htab mapping range as executable that overlaps with the interrupt vector region for relocatable kernel. Thanks to Ben who helped me to debug this issue and find the root cause. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/pseries: Disable relocation on exception while going down during crash.Mahesh Salgaonkar2014-02-111-2/+1
| | | | | | | | | Disable relocation on exception while going down even in kdump case. This is because we are about clear htab mappings while kexec-ing into kdump kernel and we may run into issues if we still have AIL ON. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/eeh: Drop taken reference to driver on eeh_rmv_deviceThadeu Lima de Souza Cascardo2014-02-111-2/+6
| | | | | | | | | | | | | | | Commit f5c57710dd62dd06f176934a8b4b8accbf00f9f8 ("powerpc/eeh: Use partial hotplug for EEH unaware drivers") introduces eeh_rmv_device, which may grab a reference to a driver, but not release it. That prevents a driver from being removed after it has gone through EEH recovery. This patch drops the reference if it was taken. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Fix build failure in sysdev/mpic.c for MPIC_WEIRD=yPaul Gortmaker2014-02-111-19/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 446f6d06fab0b49c61887ecbe8286d6aaa796637 ("powerpc/mpic: Properly set default triggers") breaks the mpc7447_hpc_defconfig as follows: CC arch/powerpc/sysdev/mpic.o arch/powerpc/sysdev/mpic.c: In function 'mpic_set_irq_type': arch/powerpc/sysdev/mpic.c:886:9: error: case label does not reduce to an integer constant arch/powerpc/sysdev/mpic.c:890:9: error: case label does not reduce to an integer constant arch/powerpc/sysdev/mpic.c:894:9: error: case label does not reduce to an integer constant arch/powerpc/sysdev/mpic.c:898:9: error: case label does not reduce to an integer constant Looking at the cpp output (gcc 4.7.3), I see: case mpic->hw_set[MPIC_IDX_VECPRI_SENSE_EDGE] | mpic->hw_set[MPIC_IDX_VECPRI_POLARITY_POSITIVE]: The pointer into an array appears because CONFIG_MPIC_WEIRD=y is set for this platform, thus enabling the following: ------------------- #ifdef CONFIG_MPIC_WEIRD static u32 mpic_infos[][MPIC_IDX_END] = { [0] = { /* Original OpenPIC compatible MPIC */ [...] #define MPIC_INFO(name) mpic->hw_set[MPIC_IDX_##name] #else /* CONFIG_MPIC_WEIRD */ #define MPIC_INFO(name) MPIC_##name #endif /* CONFIG_MPIC_WEIRD */ ------------------- Here we convert the case section to if/else if, and also add the equivalent of a default case to warn about unknown types. Boot tested on sbc8548, build tested on all defconfigs. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2014-02-0814-82/+123
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Peter Anvin: "Quite a varied little collection of fixes. Most of them are relatively small or isolated; the biggest one is Mel Gorman's fixes for TLB range flushing. A couple of AMD-related fixes (including not crashing when given an invalid microcode image) and fix a crash when compiled with gcov" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, microcode, AMD: Unify valid container checks x86, hweight: Fix BUG when booting with CONFIG_GCOV_PROFILE_ALL=y x86/efi: Allow mapping BGRT on x86-32 x86: Fix the initialization of physnode_map x86, cpu hotplug: Fix stack frame warning in check_irq_vectors_for_cpu_disable() x86/intel/mid: Fix X86_INTEL_MID dependencies arch/x86/mm/srat: Skip NUMA_NO_NODE while parsing SLIT mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridge x86: mm: change tlb_flushall_shift for IvyBridge x86/mm: Eliminate redundant page table walk during TLB range flushing x86/mm: Clean up inconsistencies when flushing TLB ranges mm, x86: Account for TLB flushes only when debugging x86/AMD/NB: Fix amd_set_subcaches() parameter type x86/quirks: Add workaround for AMD F16h Erratum792 x86, doc, kconfig: Fix dud URL for Microcode data
| * Merge tag 'efi-urgent' into x86/urgentH. Peter Anvin2014-02-071753-27077/+59393
| |\ | | | | | | | | | | | | | | | * Avoid WARN_ON() when mapping BGRT on Baytrail (EFI 32-bit). Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| | * x86/efi: Allow mapping BGRT on x86-32Matt Fleming2014-02-051-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_X86_32 doesn't map the boot services regions into the EFI memory map (see commit 700870119f49 ("x86, efi: Don't map Boot Services on i386")), and so efi_lookup_mapped_addr() will fail to return a valid address. Executing the ioremap() path in efi_bgrt_init() causes the following warning on x86-32 because we're trying to ioremap() RAM, WARNING: CPU: 0 PID: 0 at arch/x86/mm/ioremap.c:102 __ioremap_caller+0x2ad/0x2c0() Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.13.0-0.rc5.git0.1.2.fc21.i686 #1 Hardware name: DellInc. Venue 8 Pro 5830/09RP78, BIOS A02 10/17/2013 00000000 00000000 c0c0df08 c09a5196 00000000 c0c0df38 c0448c1e c0b41310 00000000 00000000 c0b37bc1 00000066 c043bbfd c043bbfd 00e7dfe0 00073eff 00073eff c0c0df48 c0448ce2 00000009 00000000 c0c0df9c c043bbfd 00078d88 Call Trace: [<c09a5196>] dump_stack+0x41/0x52 [<c0448c1e>] warn_slowpath_common+0x7e/0xa0 [<c043bbfd>] ? __ioremap_caller+0x2ad/0x2c0 [<c043bbfd>] ? __ioremap_caller+0x2ad/0x2c0 [<c0448ce2>] warn_slowpath_null+0x22/0x30 [<c043bbfd>] __ioremap_caller+0x2ad/0x2c0 [<c0718f92>] ? acpi_tb_verify_table+0x1c/0x43 [<c0719c78>] ? acpi_get_table_with_size+0x63/0xb5 [<c087cd5e>] ? efi_lookup_mapped_addr+0xe/0xf0 [<c043bc2b>] ioremap_nocache+0x1b/0x20 [<c0cb01c8>] ? efi_bgrt_init+0x83/0x10c [<c0cb01c8>] efi_bgrt_init+0x83/0x10c [<c0cafd82>] efi_late_init+0x8/0xa [<c0c9bab2>] start_kernel+0x3ae/0x3c3 [<c0c9b53b>] ? repair_env_string+0x51/0x51 [<c0c9b378>] i386_start_kernel+0x12e/0x131 Switch to using early_memremap(), which won't trigger this warning, and has the added benefit of more accurately conveying what we're trying to do - map a chunk of memory. This patch addresses the following bug report, https://bugzilla.kernel.org/show_bug.cgi?id=67911 Reported-by: Adam Williamson <awilliam@redhat.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
| * | x86, microcode, AMD: Unify valid container checksBorislav Petkov2014-02-061-14/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For additional coverage, BorisO and friends unknowlingly did swap AMD microcode with Intel microcode blobs in order to see what happens. What did happen on 32-bit was [ 5.722656] BUG: unable to handle kernel paging request at be3a6008 [ 5.722693] IP: [<c106d6b4>] load_microcode_amd+0x24/0x3f0 [ 5.722716] *pdpt = 0000000000000000 *pde = 0000000000000000 because there was a valid initrd there but without valid microcode in it and the container check happened *after* the relocated ramdisk handling on 32-bit, which was clearly wrong. While at it, take care of the ramdisk relocation on both 32- and 64-bit as it is done on both. Also, comment what we're doing because this code is a bit tricky. Reported-and-tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1391460104-7261-1-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86: Fix the initialization of physnode_mapPetr Tesarik2014-02-011-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With DISCONTIGMEM, the mapping between a pfn and its owning node is initialized using data provided by the BIOS. However, the initialization may fail if the extents are not aligned to section boundary (64M). The symptom of this bug is an early boot failure in pfn_to_page(), as it tries to access NODE_DATA(__nid) using index from an unitialized element of the physnode_map[] array. While the bug is always present, it is more likely to be hit in kdump kernels on large machines, because: 1. The memory map for a kdump kernel is specified as exactmap, and exactmap is more likely to be unaligned. 2. Large reservations are more likely to span across a 64M boundary. [ hpa: fixed incorrect use of "pfn" instead of "start" ] Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Link: http://lkml.kernel.org/r/20140201133019.32e56f86@hananiah.suse.cz Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86, cpu hotplug: Fix stack frame warning in check_irq_vectors_for_cpu_disable()Prarit Bhargava2014-01-301-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Further discussion here: http://marc.info/?l=linux-kernel&m=139073901101034&w=2 kbuild, 0day kernel build service, outputs the warning: arch/x86/kernel/irq.c:333:1: warning: the frame size of 2056 bytes is larger than 2048 bytes [-Wframe-larger-than=] because check_irq_vectors_for_cpu_disable() allocates two cpumasks on the stack. Fix this by moving the two cpumasks to a global file context. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: David Rientjes <rientjes@google.com> Signed-off-by: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1390915331-27375-1-git-send-email-prarit@redhat.com Cc: Andi Kleen <ak@linux.intel.com> Cc: Michel Lespinasse <walken@google.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Yang Zhang <yang.z.zhang@Intel.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Janet Morgan <janet.morgan@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Ruiv Wang <ruiv.wang@gmail.com> Cc: Gong Chen <gong.chen@linux.intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | x86/intel/mid: Fix X86_INTEL_MID dependenciesDavid Cohen2014-01-251-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the following warning: warning: (X86_INTEL_MID) selects INTEL_SCU_IPC which has unmet direct dependencies (X86 && X86_PLATFORM_DEVICES && X86_INTEL_MID) It happens because when selected, X86_INTEL_MID tries to select INTEL_SCU_IPC regardless all its dependencies are met or not. This patch fixes it by adding the missing X86_PLATFORM_DEVICES dependency to X86_INTEL_MID. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: David Cohen <david.a.cohen@linux.intel.com> Link: http://lkml.kernel.org/r/1390329699-20782-1-git-send-email-david.a.cohen@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | Merge branch 'linus' into x86/urgentIngo Molnar2014-01-25376-7819/+9389
| |\ \ | | | | | | | | | | | | | | | | | | | | Merge in the x86 changes to apply a fix. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | arch/x86/mm/srat: Skip NUMA_NO_NODE while parsing SLITToshi Kani2014-01-251-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When ACPI SLIT table has an I/O locality (i.e. a locality unique to an I/O device), numa_set_distance() emits this warning message: NUMA: Warning: node ids are out of bound, from=-1 to=-1 distance=10 acpi_numa_slit_init() calls numa_set_distance() with pxm_to_node(), which assumes that all localities have been parsed with SRAT previously. SRAT does not list I/O localities, where as SLIT lists all localities including I/Os. Hence, pxm_to_node() returns NUMA_NO_NODE (-1) for an I/O locality. I/O localities are not supported and are ignored today, but emitting such warning message leads to unnecessary confusion. Change acpi_numa_slit_init() to avoid calling numa_set_distance() with NUMA_NO_NODE. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/n/tip-dSvpjjvp8aMzs1ybkftxohlh@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridgeMel Gorman2014-01-252-11/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a large ebizzy performance regression that was bisected to commit 611ae8e3 (x86/tlb: enable tlb flush range support for x86). The problem was related to the tlb_flushall_shift tuning for IvyBridge which was altered. The problem is that it is not clear if the tuning values for each CPU family is correct as the methodology used to tune the values is unclear. This patch uses a conservative tlb_flushall_shift value for all CPU families except IvyBridge so the decision can be revisited if any regression is found as a result of this change. IvyBridge is an exception as testing with one methodology determined that the value of 2 is acceptable. Details are in the changelog for the patch "x86: mm: Change tlb_flushall_shift for IvyBridge". One important aspect of this to watch out for is Xen. The original commit log mentioned large performance gains on Xen. It's possible Xen is more sensitive to this value if it flushes small ranges of pages more frequently than workloads on bare metal typically do. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alex Shi <alex.shi@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-dyzMww3fqugnhbhgo6Gxmtkw@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86: mm: change tlb_flushall_shift for IvyBridgeMel Gorman2014-01-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a large performance regression that was bisected to commit 611ae8e3 ("x86/tlb: enable tlb flush range support for x86"). This patch simply changes the default balance point between a local and global flush for IvyBridge. In the interest of allowing the tests to be reproduced, this patch was tested using mmtests 0.15 with the following configurations configs/config-global-dhp__tlbflush-performance configs/config-global-dhp__scheduler-performance configs/config-global-dhp__network-performance Results are from two machines Ivybridge 4 threads: Intel(R) Core(TM) i3-3240 CPU @ 3.40GHz Ivybridge 8 threads: Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz Page fault microbenchmark showed nothing interesting. Ebizzy was configured to run multiple iterations and threads. Thread counts ranged from 1 to NR_CPUS*2. For each thread count, it ran 100 iterations and each iteration lasted 10 seconds. Ivybridge 4 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 6395.44 ( 0.00%) 6789.09 ( 6.16%) Mean 2 7012.85 ( 0.00%) 8052.16 ( 14.82%) Mean 3 6403.04 ( 0.00%) 6973.74 ( 8.91%) Mean 4 6135.32 ( 0.00%) 6582.33 ( 7.29%) Mean 5 6095.69 ( 0.00%) 6526.68 ( 7.07%) Mean 6 6114.33 ( 0.00%) 6416.64 ( 4.94%) Mean 7 6085.10 ( 0.00%) 6448.51 ( 5.97%) Mean 8 6120.62 ( 0.00%) 6462.97 ( 5.59%) Ivybridge 8 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 7336.65 ( 0.00%) 7787.02 ( 6.14%) Mean 2 8218.41 ( 0.00%) 9484.13 ( 15.40%) Mean 3 7973.62 ( 0.00%) 8922.01 ( 11.89%) Mean 4 7798.33 ( 0.00%) 8567.03 ( 9.86%) Mean 5 7158.72 ( 0.00%) 8214.23 ( 14.74%) Mean 6 6852.27 ( 0.00%) 7952.45 ( 16.06%) Mean 7 6774.65 ( 0.00%) 7536.35 ( 11.24%) Mean 8 6510.50 ( 0.00%) 6894.05 ( 5.89%) Mean 12 6182.90 ( 0.00%) 6661.29 ( 7.74%) Mean 16 6100.09 ( 0.00%) 6608.69 ( 8.34%) Ebizzy hits the worst case scenario for TLB range flushing every time and it shows for these Ivybridge CPUs at least that the default choice is a poor on. The patch addresses the problem. Next was a tlbflush microbenchmark written by Alex Shi at http://marc.info/?l=linux-kernel&m=133727348217113 . It measures access costs while the TLB is being flushed. The expectation is that if there are always full TLB flushes that the benchmark would suffer and it benefits from range flushing There are 320 iterations of the test per thread count. The number of entries is randomly selected with a min of 1 and max of 512. To ensure a reasonably even spread of entries, the full range is broken up into 8 sections and a random number selected within that section. iteration 1, random number between 0-64 iteration 2, random number between 64-128 etc This is still a very weak methodology. When you do not know what are typical ranges, random is a reasonable choice but it can be easily argued that the opimisation was for smaller ranges and an even spread is not representative of any workload that matters. To improve this, we'd need to know the probability distribution of TLB flush range sizes for a set of workloads that are considered "common", build a synthetic trace and feed that into this benchmark. Even that is not perfect because it would not account for the time between flushes but there are limits of what can be reasonably done and still be doing something useful. If a representative synthetic trace is provided then this benchmark could be revisited and the shift values retuned. Ivybridge 4 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 10.50 ( 0.00%) 10.50 ( 0.03%) Mean 2 17.59 ( 0.00%) 17.18 ( 2.34%) Mean 3 22.98 ( 0.00%) 21.74 ( 5.41%) Mean 5 47.13 ( 0.00%) 46.23 ( 1.92%) Mean 8 43.30 ( 0.00%) 42.56 ( 1.72%) Ivybridge 8 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 9.45 ( 0.00%) 9.36 ( 0.93%) Mean 2 9.37 ( 0.00%) 9.70 ( -3.54%) Mean 3 9.36 ( 0.00%) 9.29 ( 0.70%) Mean 5 14.49 ( 0.00%) 15.04 ( -3.75%) Mean 8 41.08 ( 0.00%) 38.73 ( 5.71%) Mean 13 32.04 ( 0.00%) 31.24 ( 2.49%) Mean 16 40.05 ( 0.00%) 39.04 ( 2.51%) For both CPUs, average access time is reduced which is good as this is the benchmark that was used to tune the shift values in the first place albeit it is now known *how* the benchmark was used. The scheduler benchmarks were somewhat inconclusive. They showed gains and losses and makes me reconsider how stable those benchmarks really are or if something else might be interfering with the test results recently. Network benchmarks were inconclusive. Almost all results were flat except for netperf-udp tests on the 4 thread machine. These results were unstable and showed large variations between reboots. It is unknown if this is a recent problems but I've noticed before that netperf-udp results tend to vary. Based on these results, changing the default for Ivybridge seems like a logical choice. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Alex Shi <alex.shi@linaro.org> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-cqnadffh1tiqrshthRj3Esge@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86/mm: Eliminate redundant page table walk during TLB range flushingMel Gorman2014-01-251-27/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When choosing between doing an address space or ranged flush, the x86 implementation of flush_tlb_mm_range takes into account whether there are any large pages in the range. A per-page flush typically requires fewer entries than would covered by a single large page and the check is redundant. There is one potential exception. THP migration flushes single THP entries and it conceivably would benefit from flushing a single entry instead of the mm. However, this flush is after a THP allocation, copy and page table update potentially with any other threads serialised behind it. In comparison to that, the flush is noise. It makes more sense to optimise balancing to require fewer flushes than to optimise the flush itself. This patch deletes the redundant huge page check. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alex Shi <alex.shi@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-sgei1drpOcburujPsfh6ovmo@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86/mm: Clean up inconsistencies when flushing TLB rangesMel Gorman2014-01-251-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NR_TLB_LOCAL_FLUSH_ALL is not always accounted for correctly and the comparison with total_vm is done before taking tlb_flushall_shift into account. Clean it up. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Alex Shi <alex.shi@linaro.org> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Hugh Dickins <hughd@google.com> Link: http://lkml.kernel.org/n/tip-Iz5gcahrgskIldvukulzi0hh@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | mm, x86: Account for TLB flushes only when debuggingMel Gorman2014-01-253-12/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bisection between 3.11 and 3.12 fingered commit 9824cf97 ("mm: vmstats: tlb flush counters") to cause overhead problems. The counters are undeniably useful but how often do we really need to debug TLB flush related issues? It does not justify taking the penalty everywhere so make it a debugging option. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com> Cc: Alex Shi <alex.shi@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-XzxjntugxuwpxXhcrxqqh53b@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86/AMD/NB: Fix amd_set_subcaches() parameter typeDan Carpenter2014-01-252-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is under CAP_SYS_ADMIN, but Smatch complains that mask comes from the user and the test for "mask > 0xf" can underflow. The fix is simple: amd_set_subcaches() should hand down not an 'int' but an 'unsigned long' like it was originally indended to do. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Daniel J Blueman <daniel@numascale-asia.com> Link: http://lkml.kernel.org/r/20140121072209.GA22095@elgon.mountain Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86/quirks: Add workaround for AMD F16h Erratum792Aravind Gopalakrishnan2014-01-251-0/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The workaround for this Erratum is included in AGESA. But BIOSes spun only after Jan2014 will have the fix (atleast server versions of the chip). The erratum affects both embedded and server platforms and since we cannot say with certainity that ALL BIOSes on systems out in the field will have the fix, we should probably insulate ourselves in case BIOS does not do the right thing or someone is using old BIOSes. Refer to Revision Guide for AMD F16h models 00h-0fh, document 51810 Rev. 3.04, November2013 for details on the Erratum. Tested the patch on Fam16h server platform and it works fine. Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com> Cc: <hmh@hmh.eng.br> Cc: <Kim.Naru@amd.com> Cc: <Suravee.Suthikulpanit@amd.com> Cc: <bp@suse.de> Cc: <sherry.hurwitz@amd.com> Link: http://lkml.kernel.org/r/1390515212-1824-1-git-send-email-Aravind.Gopalakrishnan@amd.com [ Minor edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86, doc, kconfig: Fix dud URL for Microcode dataAlan2014-01-201-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The actual data lives in the Intel download center, and that ought to also be a reliable way to continue to find it. Unfortunately the actual URL needed for doing it directly is about a foot long so give instructions. Signed-off-by: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/r/20140120180056.7173.62222.stgit@alan.etchedpixels.co.uk Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | | | Merge tag 'arm64-fixes' of ↵Linus Torvalds2014-02-0719-66/+101
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Catalin Marinas: - Relax VDSO alignment requirements so that the kernel-picked one (4K) does not conflict with the dynamic linker's one (64K) - VDSO gettimeofday fix - Barrier fixes for atomic operations and cache flushing - TLB invalidation when overriding early page mappings during boot - Wired up new 32-bit arm (compat) syscalls - LSM_MMAP_MIN_ADDR when COMPAT is enabled - defconfig update - Clean-up (comments, pgd_alloc). * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: defconfig: Expand default enabled features arm64: asm: remove redundant "cc" clobbers arm64: atomics: fix use of acquire + release for full barrier semantics arm64: barriers: allow dsb macro to take option parameter security: select correct default LSM_MMAP_MIN_ADDR on arm on arm64 arm64: compat: Wire up new AArch32 syscalls arm64: vdso: update wtm fields for CLOCK_MONOTONIC_COARSE arm64: vdso: fix coarse clock handling arm64: simplify pgd_alloc arm64: fix typo: s/SERRROR/SERROR/ arm64: Invalidate the TLB when replacing pmd entries during boot arm64: Align CMA sizes to PAGE_SIZE arm64: add DSB after icache flush in __flush_icache_all() arm64: vdso: prevent ld from aligning PT_LOAD segments to 64k
| * | | | arm64: defconfig: Expand default enabled featuresMark Rutland2014-02-072-4/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | FPGA implementations of the Cortex-A57 and Cortex-A53 are now available in the form of the SMM-A57 and SMM-A53 Soft Macrocell Models (SMMs) for Versatile Express. As these attach to a Motherboard Express V2M-P1 it would be useful to have support for some V2M-P1 peripherals enabled by default. Additionally a couple of of features have been introduced since the last defconfig update (CMA, jump labels) that would be good to have enabled by default to ensure they are build and boot tested. This patch updates the arm64 defconfig to enable support for these devices and features. The arm64 Kconfig is modified to select HAVE_PATA_PLATFORM, which is required to enable support for the CompactFlash controller on the V2M-P1. A few options which don't need to appear in defconfig are trimmed: * BLK_DEV - selected by default * EXPERIMENTAL - otherwise gone from the kernel * MII - selected by drivers which require it * USB_SUPPORT - selected by default Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: asm: remove redundant "cc" clobbersWill Deacon2014-02-074-25/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cbnz/tbnz don't update the condition flags, so remove the "cc" clobbers from inline asm blocks that only use these instructions to implement conditional branches. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: atomics: fix use of acquire + release for full barrier semanticsWill Deacon2014-02-075-18/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linux requires a number of atomic operations to provide full barrier semantics, that is no memory accesses after the operation can be observed before any accesses up to and including the operation in program order. On arm64, these operations have been incorrectly implemented as follows: // A, B, C are independent memory locations <Access [A]> // atomic_op (B) 1: ldaxr x0, [B] // Exclusive load with acquire <op(B)> stlxr w1, x0, [B] // Exclusive store with release cbnz w1, 1b <Access [C]> The assumption here being that two half barriers are equivalent to a full barrier, so the only permitted ordering would be A -> B -> C (where B is the atomic operation involving both a load and a store). Unfortunately, this is not the case by the letter of the architecture and, in fact, the accesses to A and C are permitted to pass their nearest half barrier resulting in orderings such as Bl -> A -> C -> Bs or Bl -> C -> A -> Bs (where Bl is the load-acquire on B and Bs is the store-release on B). This is a clear violation of the full barrier requirement. The simple way to fix this is to implement the same algorithm as ARMv7 using explicit barriers: <Access [A]> // atomic_op (B) dmb ish // Full barrier 1: ldxr x0, [B] // Exclusive load <op(B)> stxr w1, x0, [B] // Exclusive store cbnz w1, 1b dmb ish // Full barrier <Access [C]> but this has the undesirable effect of introducing *two* full barrier instructions. A better approach is actually the following, non-intuitive sequence: <Access [A]> // atomic_op (B) 1: ldxr x0, [B] // Exclusive load <op(B)> stlxr w1, x0, [B] // Exclusive store with release cbnz w1, 1b dmb ish // Full barrier <Access [C]> The simple observations here are: - The dmb ensures that no subsequent accesses (e.g. the access to C) can enter or pass the atomic sequence. - The dmb also ensures that no prior accesses (e.g. the access to A) can pass the atomic sequence. - Therefore, no prior access can pass a subsequent access, or vice-versa (i.e. A is strictly ordered before C). - The stlxr ensures that no prior access can pass the store component of the atomic operation. The only tricky part remaining is the ordering between the ldxr and the access to A, since the absence of the first dmb means that we're now permitting re-ordering between the ldxr and any prior accesses. From an (arbitrary) observer's point of view, there are two scenarios: 1. We have observed the ldxr. This means that if we perform a store to [B], the ldxr will still return older data. If we can observe the ldxr, then we can potentially observe the permitted re-ordering with the access to A, which is clearly an issue when compared to the dmb variant of the code. Thankfully, the exclusive monitor will save us here since it will be cleared as a result of the store and the ldxr will retry. Notice that any use of a later memory observation to imply observation of the ldxr will also imply observation of the access to A, since the stlxr/dmb ensure strict ordering. 2. We have not observed the ldxr. This means we can perform a store and influence the later ldxr. However, that doesn't actually tell us anything about the access to [A], so we've not lost anything here either when compared to the dmb variant. This patch implements this solution for our barriered atomic operations, ensuring that we satisfy the full barrier requirements where they are needed. Cc: <stable@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: barriers: allow dsb macro to take option parameterWill Deacon2014-02-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The dsb instruction takes an option specifying both the target access types and shareability domain. This patch allows such an option to be passed to the dsb macro, resulting in potentially more efficient code. Currently the option is ignored until all callers are updated (unlike ARM, the option is mandated by the assembler). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: compat: Wire up new AArch32 syscallsCatalin Marinas2014-02-051-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch enables sys_compat, sys_finit_module, sys_sched_setattr and sys_sched_getattr for compat (AArch32) applications. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: vdso: update wtm fields for CLOCK_MONOTONIC_COARSENathan Lynch2014-02-051-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update wall-to-monotonic fields in the VDSO data page unconditionally. These are used to service CLOCK_MONOTONIC_COARSE, which is not guarded by use_syscall. Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: vdso: fix coarse clock handlingNathan Lynch2014-02-051-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When __kernel_clock_gettime is called with a CLOCK_MONOTONIC_COARSE or CLOCK_REALTIME_COARSE clock id, it returns incorrectly to whatever the caller has placed in x2 ("ret x2" to return from the fast path). Fix this by saving x30/LR to x2 only in code that will call __do_get_tspec, restoring x30 afterward, and using a plain "ret" to return from the routine. Also: while the resulting tv_nsec value for CLOCK_REALTIME and CLOCK_MONOTONIC must be computed using intermediate values that are left-shifted by cs_shift (x12, set by __do_get_tspec), the results for coarse clocks should be calculated using unshifted values (xtime_coarse_nsec is in units of actual nanoseconds). The current code shifts intermediate values by x12 unconditionally, but x12 is uninitialized when servicing a coarse clock. Fix this by setting x12 to 0 once we know we are dealing with a coarse clock id. Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: simplify pgd_allocMark Rutland2014-02-051-9/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently pgd_alloc has a redundant NULL check in its return path that can be removed with no ill effects. With that removed it's also possible to return early and eliminate the new_pgd temporary variable. This patch applies said modifications, making the logic of pgd_alloc correspond 1-1 with that of pgd_free. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: fix typo: s/SERRROR/SERROR/Mark Rutland2014-02-052-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Somehow SERROR has acquired an additional 'R' in a couple of headers. This patch removes them before they spread further. As neither instance is in use yet, no other sites need to be fixed up. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: Invalidate the TLB when replacing pmd entries during bootCatalin Marinas2014-02-051-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the 64K page size configuration, __create_page_tables in head.S maps enough memory to get started but using 64K pages rather than 512M sections with a single pgd/pud/pmd entry pointing to a pte table. create_mapping() may override the pgd/pud/pmd table entry with a block (section) one if the RAM size is more than 512MB and aligned correctly. For the end of this block to be accessible, the old TLB entry must be invalidated. Cc: <stable@vger.kernel.org> Reported-by: Mark Salter <msalter@redhat.com> Tested-by: Mark Salter <msalter@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: Align CMA sizes to PAGE_SIZELaura Abbott2014-02-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dma_alloc_from_contiguous takes number of pages for a size. Align up the dma size passed in to page size to avoid truncation and allocation failures on sizes less than PAGE_SIZE. Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: add DSB after icache flush in __flush_icache_all()Vinayak Kale2014-02-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add DSB after icache flush to complete the cache maintenance operation. The function __flush_icache_all() is used only for user space mappings and an ISB is not required because of an exception return before executing user instructions. An exception return would behave like an ISB. Signed-off-by: Vinayak Kale <vkale@apm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: vdso: prevent ld from aligning PT_LOAD segments to 64kWill Deacon2014-02-041-1/+1
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Whilst the text segment for our VDSO is marked as PT_LOAD in the ELF headers, it is mapped by the kernel and not actually subject to demand-paging. ld doesn't realise this, and emits a p_align field of 64k (the maximum supported page size), which conflicts with the load address picked by the kernel on 4k systems, which will be 4k aligned. This causes GDB to fail with "Failed to read a valid object file image from memory" when attempting to load the VDSO. This patch passes the -n option to ld, which prevents it from aligning PT_LOAD segments to the maximum page size. Cc: <stable@vger.kernel.org> Reported-by: Kyle McMartin <kyle@redhat.com> Acked-by: Kyle McMartin <kyle@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* | | | Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds2014-02-077-11/+24
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MIPS updates from Ralf Baechle: "hree minor patches. All have sat in -next for a few days" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: fpu.h: Fix build when CONFIG_BUG is not set MIPS: Wire up sched_setattr/sched_getattr syscalls MIPS: Alchemy: Fix DB1100 GPIO registration
| * | | | MIPS: fpu.h: Fix build when CONFIG_BUG is not setAaro Koskinen2014-02-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __enable_fpu produces a build failure when CONFIG_BUG is not set: In file included from arch/mips/kernel/cpu-probe.c:24:0: arch/mips/include/asm/fpu.h: In function '__enable_fpu': arch/mips/include/asm/fpu.h:77:1: error: control reaches end of non-void function [-Werror=return-type] This is regression introduced in 3.14-rc1. Fix that. Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: Paul Burton <paul.burton@imgtec.com> Cc: John Crispin <blogic@openwrt.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6504/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| * | | | MIPS: Wire up sched_setattr/sched_getattr syscallsJames Hogan2014-02-045-6/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Wire up for MIPS the new sched_setattr and sched_getattr system calls added in commit d50dde5a10f3 (sched: Add new scheduler syscalls to support an extended scheduling parameters ABI) merged in v3.14-rc1. Signed-off-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Markos Chandras <markos.chandras@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6502/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>