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2019-11-15dm integrity: fix excessive alignment of metadata runsMikulas Patocka
Metadata runs are supposed to be aligned on 4k boundary (so that they work efficiently with disks with 4k sectors). However, there was a programming bug that makes them aligned on 128k boundary instead. The unused space is wasted. Fix this bug by providing a proper 4k alignment. In order to keep existing volumes working, we introduce a new flag SB_FLAG_FIXED_PADDING - when the flag is clear, we calculate the padding the old way. In order to make sure that the old version cannot mount the volume created by the new version, we increase superblock version to 4. Also in order to not break with old integritysetup, we fix alignment only if the parameter "fix_padding" is present when formatting the device. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-12Revert "Documentation: admin-guide: add earlycon documentation for RISC-V"Jonathan Corbet
This reverts commit 7f70ae564b807f81263326d641514c6dca88e5ef. Christoph H. notes that the information is redundant, and Paul W. agrees with reverting. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-10EDAC/Documentation: Describe CPER module definition and DIMM ranksRobert Richter
Update on CPER DIMM naming convention and DIMM ranks. [ bp: Touchups. ] Signed-off-by: Robert Richter <rrichter@marvell.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Cc: "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org> Cc: "linux-edac@vger.kernel.org" <linux-edac@vger.kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20191106093239.25517-14-rrichter@marvell.com
2019-11-08Merge branch 'for-next/perf' into for-next/coreCatalin Marinas
- Support for additional PMU topologies on HiSilicon platforms - Support for CCN-512 interconnect PMU - Support for AXI ID filtering in the IMX8 DDR PMU - Support for the CCPI2 uncore PMU in ThunderX2 - Driver cleanup to use devm_platform_ioremap_resource() * for-next/perf: drivers/perf: hisi: update the sccl_id/ccl_id for certain HiSilicon platform perf/imx_ddr: Dump AXI ID filter info to userspace docs/perf: Add AXI ID filter capabilities information perf/imx_ddr: Add driver for DDR PMU in i.MX8MPlus perf/imx_ddr: Add enhanced AXI ID filter support bindings: perf: imx-ddr: Add new compatible string docs/perf: Add explanation for DDR_CAP_AXI_ID_FILTER_ENHANCED quirk arm64: perf: Simplify the ARMv8 PMUv3 event attributes drivers/perf: Add CCPI2 PMU support in ThunderX2 UNCORE driver. Documentation: perf: Update documentation for ThunderX2 PMU uncore driver Documentation: Add documentation for CCN-512 DTS binding perf: arm-ccn: Enable stats for CCN-512 interconnect perf/smmuv3: use devm_platform_ioremap_resource() to simplify code perf/arm-cci: use devm_platform_ioremap_resource() to simplify code perf/arm-ccn: use devm_platform_ioremap_resource() to simplify code perf: xgene: use devm_platform_ioremap_resource() to simplify code perf: hisi: use devm_platform_ioremap_resource() to simplify code
2019-11-07docs: admin-guide: Remove threads-max auto-tuningMasanari Iida
Since following path was merged in 5.4-rc3, auto-tuning feature in threads-max does not exist any more. Fix the admin-guide document as is. kernel/sysctl.c: do not override max_threads provided by userspace b0f53dbc4bc4c371f38b14c391095a3bb8a0bb40 Fixes: b0f53dbc4bc4 ("kernel/sysctl.c: do not override max_threads provided by userspace") Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-07docs: admin-guide: Fix min value of threads-max in kernel.rstMasanari Iida
Since following patch was merged 5.4-rc3, minimum value for threads-max changed to 1. kernel/sysctl.c: do not override max_threads provided by userspace b0f53dbc4bc4c371f38b14c391095a3bb8a0bb40 Fixes: b0f53dbc4bc4 ("kernel/sysctl.c: do not override max_threads provided by userspace") Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-07x86/efi: Add efi_fake_mem support for EFI_MEMORY_SPDan Williams
Given that EFI_MEMORY_SP is platform BIOS policy decision for marking memory ranges as "reserved for a specific purpose" there will inevitably be scenarios where the BIOS omits the attribute in situations where it is desired. Unlike other attributes if the OS wants to reserve this memory from the kernel the reservation needs to happen early in init. So early, in fact, that it needs to happen before e820__memblock_setup() which is a pre-requisite for efi_fake_memmap() that wants to allocate memory for the updated table. Introduce an x86 specific efi_fake_memmap_early() that can search for attempts to set EFI_MEMORY_SP via efi_fake_mem and update the e820 table accordingly. The KASLR code that scans the command line looking for user-directed memory reservations also needs to be updated to consider "efi_fake_mem=nn@ss:0x40000" requests. Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-11-07efi: Common enable/disable infrastructure for EFI soft reservationDan Williams
UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the interpretation of the EFI Memory Types as "reserved for a specific purpose". The proposed Linux behavior for specific purpose memory is that it is reserved for direct-access (device-dax) by default and not available for any kernel usage, not even as an OOM fallback. Later, through udev scripts or another init mechanism, these device-dax claimed ranges can be reconfigured and hot-added to the available System-RAM with a unique node identifier. This device-dax management scheme implements "soft" in the "soft reserved" designation by allowing some or all of the reservation to be recovered as typical memory. This policy can be disabled at compile-time with CONFIG_EFI_SOFT_RESERVE=n, or runtime with efi=nosoftreserve. As for this patch, define the common helpers to determine if the EFI_MEMORY_SP attribute should be honored. The determination needs to be made early to prevent the kernel from being loaded into soft-reserved memory, or otherwise allowing early allocations to land there. Follow-on changes are needed per architecture to leverage these helpers in their respective mem-init paths. Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-11-05dm raid: to ensure resynchronization, perform raid set grow in preresumeHeinz Mauelshagen
This fixes a flaw causing raid set extensions not to be synchronized in case the MD bitmap resize required additional pages to be allocated. Also share resize code in the raid constructor between new size changes and those occuring during recovery. Bump the target version to define the change and document it in Documentation/admin-guide/device-mapper/dm-raid.rst. Reported-by: Steve D <steved424@gmail.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-04Documentation: Add ITLB_MULTIHIT documentationGomez Iglesias, Antonio
Add the initial ITLB_MULTIHIT documentation. [ tglx: Add it to the index so it gets actually built. ] Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Nelson D'Souza <nelson.dsouza@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-11-04kvm: x86: mmu: Recovery of shattered NX large pagesJunaid Shahid
The page table pages corresponding to broken down large pages are zapped in FIFO order, so that the large page can potentially be recovered, if it is not longer being used for execution. This removes the performance penalty for walking deeper EPT page tables. By default, one large page will last about one hour once the guest reaches a steady state. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-11-04docs/perf: Add AXI ID filter capabilities informationJoakim Zhang
Add capabilities information for AXI ID filter. Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-11-04docs/perf: Add explanation for DDR_CAP_AXI_ID_FILTER_ENHANCED quirkJoakim Zhang
Add explanation for DDR_CAP_AXI_ID_FILTER_ENHANCED quirk. Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> [will: Simplified wording] Signed-off-by: Will Deacon <will@kernel.org>
2019-11-04kvm: mmu: ITLB_MULTIHIT mitigationPaolo Bonzini
With some Intel processors, putting the same virtual address in the TLB as both a 4 KiB and 2 MiB page can confuse the instruction fetch unit and cause the processor to issue a machine check resulting in a CPU lockup. Unfortunately when EPT page tables use huge pages, it is possible for a malicious guest to cause this situation. Add a knob to mark huge pages as non-executable. When the nx_huge_pages parameter is enabled (and we are using EPT), all huge pages are marked as NX. If the guest attempts to execute in one of those pages, the page is broken down into 4K pages, which are then marked executable. This is not an issue for shadow paging (except nested EPT), because then the host is in control of TLB flushes and the problematic situation cannot happen. With nested EPT, again the nested guest can cause problems shadow and direct EPT is treated in the same way. [ tglx: Fixup default to auto and massage wording a bit ] Originally-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-10-29Merge tag 'v5.4-rc4' into docs-nextJonathan Corbet
I need to pick up the independent changes made to Documentation/core-api/memory-allocation.rst to be able to merge further work without creating a total mess.
2019-10-29Documentation: perf: Update documentation for ThunderX2 PMU uncore driverGanapatrao Prabhakerrao Kulkarni
Add documentation for Cavium Coherent Processor Interconnect (CCPI2) PMU. Signed-off-by: Ganapatrao Prabhakerrao Kulkarni <gkulkarni@marvell.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-10-28x86/speculation/taa: Add documentation for TSX Async AbortPawan Gupta
Add the documenation for TSX Async Abort. Include the description of the issue, how to check the mitigation state, control the mitigation, guidance for system administrators. [ bp: Add proper SPDX tags, touch ups by Josh and me. ] Co-developed-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-10-28x86/tsx: Add "auto" option to the tsx= cmdline parameterPawan Gupta
Platforms which are not affected by X86_BUG_TAA may want the TSX feature enabled. Add "auto" option to the TSX cmdline parameter. When tsx=auto disable TSX when X86_BUG_TAA is present, otherwise enable TSX. More details on X86_BUG_TAA can be found here: https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html [ bp: Extend the arg buffer to accommodate "auto\0". ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-10-28x86/cpu: Add a "tsx=" cmdline option with TSX disabled by defaultPawan Gupta
Add a kernel cmdline parameter "tsx" to control the Transactional Synchronization Extensions (TSX) feature. On CPUs that support TSX control, use "tsx=on|off" to enable or disable TSX. Not specifying this option is equivalent to "tsx=off". This is because on certain processors TSX may be used as a part of a speculative side channel attack. Carve out the TSX controlling functionality into a separate compilation unit because TSX is a CPU feature while the TSX async abort control machinery will go to cpu/bugs.c. [ bp: - Massage, shorten and clear the arg buffer. - Clarifications of the tsx= possible options - Josh. - Expand on TSX_CTRL availability - Pawan. ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-10-27Merge 5.4-rc5 into driver-core-nextGreg Kroah-Hartman
We want the sysfs fix in here as well to build on top of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-25PCI/DPC: Add "pcie_ports=dpc-native" to allow DPC without AER controlOlof Johansson
Prior to eed85ff4c0da7 ("PCI/DPC: Enable DPC only if AER is available"), Linux handled DPC events regardless of whether firmware had granted it ownership of AER or DPC, e.g., via _OSC. PCIe r5.0, sec 6.2.10, recommends that the OS link control of DPC to control of AER, so after eed85ff4c0da7, Linux handles DPC events only if it has control of AER. On platforms that do not grant OS control of AER via _OSC, Linux DPC handling worked before eed85ff4c0da7 but not after. To make Linux DPC handling work on those platforms the same way they did before, add a "pcie_ports=dpc-native" kernel parameter that makes Linux handle DPC events regardless of whether it has control of AER. [bhelgaas: commit log, move pcie_ports_dpc_native to drivers/pci/] Link: https://lore.kernel.org/r/20191023192205.97024-1-olof@lixom.net Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-10-23PCI: Add "pci=hpmmiosize" and "pci=hpmmioprefsize" parametersNicholas Johnson
The existing "pci=hpmemsize=nn[KMG]" kernel parameter overrides the default size of both the non-prefetchable and the prefetchable MMIO windows for hotplug bridges. Add "pci=hpmmiosize=nn[KMG]" to override the default size of only the non-prefetchable MMIO window. Add "pci=hpmmioprefsize=nn[KMG]" to override the default size of only the prefetchable MMIO window. Link: https://lore.kernel.org/r/SL2P216MB0187E4D0055791957B7E2660806B0@SL2P216MB0187.KORP216.PROD.OUTLOOK.COM Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-10-21arm64: Retrieve stolen time as paravirtualized guestSteven Price
Enable paravirtualization features when running under a hypervisor supporting the PV_TIME_ST hypercall. For each (v)CPU, we ask the hypervisor for the location of a shared page which the hypervisor will use to report stolen time to us. We set pv_time_ops to the stolen time function which simply reads the stolen value from the shared page for a VCPU. We guarantee single-copy atomicity using READ_ONCE which means we can also read the stolen time for another VCPU than the currently running one while it is potentially being updated by the hypervisor. Signed-off-by: Steven Price <steven.price@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-10-18Updated iostats docsAlbert Vaca Cintora
Previous docs mentioned 11 unsigned long fields, when the reality is that we have 15 fields with a mix of unsigned long and unsigned int. Signed-off-by: Albert Vaca Cintora <albertvaka@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-16serial: fsl_linflexuart: Be consistent with the nameStefan-Gabriel Mirea
For consistency reasons, spell the controller name as "LINFlexD" in comments and documentation. Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com> Link: https://lore.kernel.org/r/1571230107-8493-4-git-send-email-stefan-gabriel.mirea@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-15docs: admin-guide: dell_rbu: Improve formatting and spellingJonathan Neuschäfer
This improves readability a bit. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-15docs: admin-guide: dell_rbu: Rework the titleJonathan Neuschäfer
- Mention the driver name, which is also used in sysfs (dell_rbu) - Rewrite the title to be more concise Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-15docs: admin-guide: Move Dell RBU document from driver-apiJonathan Neuschäfer
This document describes how an admin can use the dell_rbu driver, rather than any in-kernel API details. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-15docs: admin-guide: Sort the "unordered guides" to avoid merge conflictsJonathan Neuschäfer
Since the "unordered guides" linked in admin-guide/index.rst are not supposed to be in any particular order, let's sort them alphabetically to avoid the risk of merge conflicts by spreading newly added lines more evenly. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-12Merge tag 'for-linus-5.4-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - correct panic handling when running as a Xen guest - cleanup the Xen grant driver to remove printing a pointer being always NULL - remove a soon to be wrong call of of_dma_configure() * tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Stop abusing DT of_dma_configure API xen/grant-table: remove unnecessary printing x86/xen: Return from panic notifier
2019-10-11docs: SafeSetID.rst: Remove spurious '???' charactersChristian Kujau
It appears that some smart quotes were changed to "???" by even smarter software; change them to the dumb but legible variety. Signed-off-by: Christian Kujau <lists@nerdbynature.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-10dm dust: convert documentation to ReSTBryan Gurney
Convert the dm-dust documentation to ReST formatting, using literal blocks for all of the shell command, shell output, and log output examples. Add dm-dust to index.rst. Additionally, fix an annotation in the "querying for specific bad blocks" section, on the "queryblock ... not found in badblocklist" example, to properly state that the message appears when a given block is not found. Signed-off-by: Bryan Gurney <bgurney@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-10docs: admin-guide: fix printk_ratelimit explanationOleksandr Natalenko
The printk_ratelimit value accepts seconds, not jiffies (though it is converted into jiffies internally). Update documentation to reflect this. Also, remove the statement about allowing 1 message in 5 seconds since bursts up to 10 messages are allowed by default. Finally, while we are here, mention default value for printk_ratelimit_burst too. Signed-off-by: Oleksandr Natalenko <oleksandr@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-10Documentation: admin-guide: add earlycon documentation for RISC-VPaul Walmsley
Kernels booting on RISC-V can specify "earlycon" with no options on the Linux command line, and the generic DT earlycon support will query the "chosen/stdout-path" property (if present) to determine which early console device to use. Document this appropriately in the admin-guide. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Christoph Hellwig <hch@lst.de> Cc: Andreas Schwab <schwab@suse.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-07mm, memcg: proportional memory.{low,min} reclaimChris Down
cgroup v2 introduces two memory protection thresholds: memory.low (best-effort) and memory.min (hard protection). While they generally do what they say on the tin, there is a limitation in their implementation that makes them difficult to use effectively: that cliff behaviour often manifests when they become eligible for reclaim. This patch implements more intuitive and usable behaviour, where we gradually mount more reclaim pressure as cgroups further and further exceed their protection thresholds. This cliff edge behaviour happens because we only choose whether or not to reclaim based on whether the memcg is within its protection limits (see the use of mem_cgroup_protected in shrink_node), but we don't vary our reclaim behaviour based on this information. Imagine the following timeline, with the numbers the lruvec size in this zone: 1. memory.low=1000000, memory.current=999999. 0 pages may be scanned. 2. memory.low=1000000, memory.current=1000000. 0 pages may be scanned. 3. memory.low=1000000, memory.current=1000001. 1000001* pages may be scanned. (?!) * Of course, we won't usually scan all available pages in the zone even without this patch because of scan control priority, over-reclaim protection, etc. However, as shown by the tests at the end, these techniques don't sufficiently throttle such an extreme change in input, so cliff-like behaviour isn't really averted by their existence alone. Here's an example of how this plays out in practice. At Facebook, we are trying to protect various workloads from "system" software, like configuration management tools, metric collectors, etc (see this[0] case study). In order to find a suitable memory.low value, we start by determining the expected memory range within which the workload will be comfortable operating. This isn't an exact science -- memory usage deemed "comfortable" will vary over time due to user behaviour, differences in composition of work, etc, etc. As such we need to ballpark memory.low, but doing this is currently problematic: 1. If we end up setting it too low for the workload, it won't have *any* effect (see discussion above). The group will receive the full weight of reclaim and won't have any priority while competing with the less important system software, as if we had no memory.low configured at all. 2. Because of this behaviour, we end up erring on the side of setting it too high, such that the comfort range is reliably covered. However, protected memory is completely unavailable to the rest of the system, so we might cause undue memory and IO pressure there when we *know* we have some elasticity in the workload. 3. Even if we get the value totally right, smack in the middle of the comfort zone, we get extreme jumps between no pressure and full pressure that cause unpredictable pressure spikes in the workload due to the current binary reclaim behaviour. With this patch, we can set it to our ballpark estimation without too much worry. Any undesirable behaviour, such as too much or too little reclaim pressure on the workload or system will be proportional to how far our estimation is off. This means we can set memory.low much more conservatively and thus waste less resources *without* the risk of the workload falling off a cliff if we overshoot. As a more abstract technical description, this unintuitive behaviour results in having to give high-priority workloads a large protection buffer on top of their expected usage to function reliably, as otherwise we have abrupt periods of dramatically increased memory pressure which hamper performance. Having to set these thresholds so high wastes resources and generally works against the principle of work conservation. In addition, having proportional memory reclaim behaviour has other benefits. Most notably, before this patch it's basically mandatory to set memory.low to a higher than desirable value because otherwise as soon as you exceed memory.low, all protection is lost, and all pages are eligible to scan again. By contrast, having a gradual ramp in reclaim pressure means that you now still get some protection when thresholds are exceeded, which means that one can now be more comfortable setting memory.low to lower values without worrying that all protection will be lost. This is important because workingset size is really hard to know exactly, especially with variable workloads, so at least getting *some* protection if your workingset size grows larger than you expect increases user confidence in setting memory.low without a huge buffer on top being needed. Thanks a lot to Johannes Weiner and Tejun Heo for their advice and assistance in thinking about how to make this work better. In testing these changes, I intended to verify that: 1. Changes in page scanning become gradual and proportional instead of binary. To test this, I experimented stepping further and further down memory.low protection on a workload that floats around 19G workingset when under memory.low protection, watching page scan rates for the workload cgroup: +------------+-----------------+--------------------+--------------+ | memory.low | test (pgscan/s) | control (pgscan/s) | % of control | +------------+-----------------+--------------------+--------------+ | 21G | 0 | 0 | N/A | | 17G | 867 | 3799 | 23% | | 12G | 1203 | 3543 | 34% | | 8G | 2534 | 3979 | 64% | | 4G | 3980 | 4147 | 96% | | 0 | 3799 | 3980 | 95% | +------------+-----------------+--------------------+--------------+ As you can see, the test kernel (with a kernel containing this patch) ramps up page scanning significantly more gradually than the control kernel (without this patch). 2. More gradual ramp up in reclaim aggression doesn't result in premature OOMs. To test this, I wrote a script that slowly increments the number of pages held by stress(1)'s --vm-keep mode until a production system entered severe overall memory contention. This script runs in a highly protected slice taking up the majority of available system memory. Watching vmstat revealed that page scanning continued essentially nominally between test and control, without causing forward reclaim progress to become arrested. [0]: https://facebookmicrosites.github.io/cgroup2/docs/overview.html#case-study-the-fbtax2-project [akpm@linux-foundation.org: reflow block comments to fit in 80 cols] [chris@chrisdown.name: handle cgroup_disable=memory when getting memcg protection] Link: http://lkml.kernel.org/r/20190201045711.GA18302@chrisdown.name Link: http://lkml.kernel.org/r/20190124014455.GA6396@chrisdown.name Signed-off-by: Chris Down <chris@chrisdown.name> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Roman Gushchin <guro@fb.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Dennis Zhou <dennis@kernel.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07x86/xen: Return from panic notifierBoris Ostrovsky
Currently execution of panic() continues until Xen's panic notifier (xen_panic_event()) is called at which point we make a hypercall that never returns. This means that any notifier that is supposed to be called later as well as significant part of panic() code (such as pstore writes from kmsg_dump()) is never executed. There is no reason for xen_panic_event() to be this last point in execution since panic()'s emergency_restart() will call into xen_emergency_restart() from where we can perform our hypercall. Nevertheless, we will provide xen_legacy_crash boot option that will preserve original behavior during crash. This option could be used, for example, if running kernel dumper (which happens after panic notifiers) is undesirable. Reported-by: James Dingwall <james@dingwall.me.uk> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com>
2019-10-04of: property: Add functional dependency link from DT bindingsSaravana Kannan
Add device links after the devices are created (but before they are probed) by looking at common DT bindings like clocks and interconnects. Automatically adding device links for functional dependencies at the framework level provides the following benefits: - Optimizes device probe order and avoids the useless work of attempting probes of devices that will not probe successfully (because their suppliers aren't present or haven't probed yet). For example, in a commonly available mobile SoC, registering just one consumer device's driver at an initcall level earlier than the supplier device's driver causes 11 failed probe attempts before the consumer device probes successfully. This was with a kernel with all the drivers statically compiled in. This problem gets a lot worse if all the drivers are loaded as modules without direct symbol dependencies. - Supplier devices like clock providers, interconnect providers, etc need to keep the resources they provide active and at a particular state(s) during boot up even if their current set of consumers don't request the resource to be active. This is because the rest of the consumers might not have probed yet and turning off the resource before all the consumers have probed could lead to a hang or undesired user experience. Some frameworks (Eg: regulator) handle this today by turning off "unused" resources at late_initcall_sync and hoping all the devices have probed by then. This is not a valid assumption for systems with loadable modules. Other frameworks (Eg: clock) just don't handle this due to the lack of a clear signal for when they can turn off resources. This leads to downstream hacks to handle cases like this that can easily be solved in the upstream kernel. By linking devices before they are probed, we give suppliers a clear count of the number of dependent consumers. Once all of the consumers are active, the suppliers can turn off the unused resources without making assumptions about the number of consumers. By default we just add device-links to track "driver presence" (probe succeeded) of the supplier device. If any other functionality provided by device-links are needed, it is left to the consumer/supplier devices to change the link when they probe. kbuild test robot reported clang error about missing const Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20190904211126.47518-4-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-01Documentation: document earlycon without options for more platformsChristoph Hellwig
The earlycon options without arguments is supposed to work on all device tree platforms, not just arm64. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-01docs: perf: Add imx-ddr to documentation indexAdam Zerella
Sphinx is currently outputting a warning where the file 'imx-ddr.rst' is not included in the documentation index. Additionally, the code highlighting and doc formatting can be slightly improved. Signed-off-by: Adam Zerella <adam.zerella@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-01docs: fix memory.low description in cgroup-v2.rstJon Haslam
The current cgroup-v2.rst file contains an incorrect description of when memory is reclaimed from a cgroup that is using the 'memory.low' mechanism. This fix simply corrects the text to reflect the actual implementation. Fixes: 7854207fe954 ("mm/docs: describe memory.low refinements") Signed-off-by: Jon Haslam <jonhaslam@fb.com> Acked-by: Roman Gushchin <guro@fb.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-09-28Merge branch 'next-lockdown' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull kernel lockdown mode from James Morris: "This is the latest iteration of the kernel lockdown patchset, from Matthew Garrett, David Howells and others. From the original description: This patchset introduces an optional kernel lockdown feature, intended to strengthen the boundary between UID 0 and the kernel. When enabled, various pieces of kernel functionality are restricted. Applications that rely on low-level access to either hardware or the kernel may cease working as a result - therefore this should not be enabled without appropriate evaluation beforehand. The majority of mainstream distributions have been carrying variants of this patchset for many years now, so there's value in providing a doesn't meet every distribution requirement, but gets us much closer to not requiring external patches. There are two major changes since this was last proposed for mainline: - Separating lockdown from EFI secure boot. Background discussion is covered here: https://lwn.net/Articles/751061/ - Implementation as an LSM, with a default stackable lockdown LSM module. This allows the lockdown feature to be policy-driven, rather than encoding an implicit policy within the mechanism. The new locked_down LSM hook is provided to allow LSMs to make a policy decision around whether kernel functionality that would allow tampering with or examining the runtime state of the kernel should be permitted. The included lockdown LSM provides an implementation with a simple policy intended for general purpose use. This policy provides a coarse level of granularity, controllable via the kernel command line: lockdown={integrity|confidentiality} Enable the kernel lockdown feature. If set to integrity, kernel features that allow userland to modify the running kernel are disabled. If set to confidentiality, kernel features that allow userland to extract confidential information from the kernel are also disabled. This may also be controlled via /sys/kernel/security/lockdown and overriden by kernel configuration. New or existing LSMs may implement finer-grained controls of the lockdown features. Refer to the lockdown_reason documentation in include/linux/security.h for details. The lockdown feature has had signficant design feedback and review across many subsystems. This code has been in linux-next for some weeks, with a few fixes applied along the way. Stephen Rothwell noted that commit 9d1f8be5cf42 ("bpf: Restrict bpf when kernel lockdown is in confidentiality mode") is missing a Signed-off-by from its author. Matthew responded that he is providing this under category (c) of the DCO" * 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits) kexec: Fix file verification on S390 security: constify some arrays in lockdown LSM lockdown: Print current->comm in restriction messages efi: Restrict efivar_ssdt_load when the kernel is locked down tracefs: Restrict tracefs when the kernel is locked down debugfs: Restrict debugfs when the kernel is locked down kexec: Allow kexec_file() with appropriate IMA policy when locked down lockdown: Lock down perf when in confidentiality mode bpf: Restrict bpf when kernel lockdown is in confidentiality mode lockdown: Lock down tracing and perf kprobes when in confidentiality mode lockdown: Lock down /proc/kcore x86/mmiotrace: Lock down the testmmiotrace module lockdown: Lock down module params that specify hardware parameters (eg. ioport) lockdown: Lock down TIOCSSERIAL lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down acpi: Disable ACPI table override if the kernel is locked down acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down ACPI: Limit access to custom_method when the kernel is locked down x86/msr: Restrict MSR access when the kernel is locked down x86: Lock down IO port access when the kernel is locked down ...
2019-09-24Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - a few hot fixes - ocfs2 updates - almost all of -mm (slab-generic, slab, slub, kmemleak, kasan, cleanups, debug, pagecache, memcg, gup, pagemap, memory-hotplug, sparsemem, vmalloc, initialization, z3fold, compaction, mempolicy, oom-kill, hugetlb, migration, thp, mmap, madvise, shmem, zswap, zsmalloc) * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits) mm/zsmalloc.c: fix a -Wunused-function warning zswap: do not map same object twice zswap: use movable memory if zpool support allocate movable memory zpool: add malloc_support_movable to zpool_driver shmem: fix obsolete comment in shmem_getpage_gfp() mm/madvise: reduce code duplication in error handling paths mm: mmap: increase sockets maximum memory size pgoff for 32bits mm/mmap.c: refine find_vma_prev() with rb_last() riscv: make mmap allocation top-down by default mips: use generic mmap top-down layout and brk randomization mips: replace arch specific way to determine 32bit task with generic version mips: adjust brk randomization offset to fit generic version mips: use STACK_TOP when computing mmap base address mips: properly account for stack randomization and stack guard gap arm: use generic mmap top-down layout and brk randomization arm: use STACK_TOP when computing mmap base address arm: properly account for stack randomization and stack guard gap arm64, mm: make randomization selected by generic topdown mmap layout arm64, mm: move generic mmap layout functions to mm arm64: consider stack randomization for mmap base only when necessary ...
2019-09-24memcg, kmem: deprecate kmem.limit_in_bytesMichal Hocko
Cgroup v1 memcg controller has exposed a dedicated kmem limit to users which turned out to be really a bad idea because there are paths which cannot shrink the kernel memory usage enough to get below the limit (e.g. because the accounted memory is not reclaimable). There are cases when the failure is even not allowed (e.g. __GFP_NOFAIL). This means that the kmem limit is in excess to the hard limit without any way to shrink and thus completely useless. OOM killer cannot be invoked to handle the situation because that would lead to a premature oom killing. As a result many places might see ENOMEM returning from kmalloc and result in unexpected errors. E.g. a global OOM killer when there is a lot of free memory because ENOMEM is translated into VM_FAULT_OOM in #PF path and therefore pagefault_out_of_memory would result in OOM killer. Please note that the kernel memory is still accounted to the overall limit along with the user memory so removing the kmem specific limit should still allow to contain kernel memory consumption. Unlike the kmem one, though, it invokes memory reclaim and targeted memcg oom killing if necessary. Start the deprecation process by crying to the kernel log. Let's see whether there are relevant usecases and simply return to EINVAL in the second stage if nobody complains in few releases. [akpm@linux-foundation.org: tweak documentation text] Link: http://lkml.kernel.org/r/20190911151612.GI4023@dhcp22.suse.cz Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Thomas Lindroth <thomas.lindroth@gmail.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24mm, page_owner, debug_pagealloc: save and dump freeing stack traceVlastimil Babka
The debug_pagealloc functionality is useful to catch buggy page allocator users that cause e.g. use after free or double free. When page inconsistency is detected, debugging is often simpler by knowing the call stack of process that last allocated and freed the page. When page_owner is also enabled, we record the allocation stack trace, but not freeing. This patch therefore adds recording of freeing process stack trace to page owner info, if both page_owner and debug_pagealloc are configured and enabled. With only page_owner enabled, this info is not useful for the memory leak debugging use case. dump_page() is adjusted to print the info. An example result of calling __free_pages() twice may look like this (note the page last free stack trace): BUG: Bad page state in process bash pfn:13d8f8 page:ffffc31984f63e00 refcount:-1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x1affff800000000() raw: 01affff800000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 ffffffffffffffff 0000000000000000 page dumped because: nonzero _refcount page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL) prep_new_page+0x143/0x150 get_page_from_freelist+0x289/0x380 __alloc_pages_nodemask+0x13c/0x2d0 khugepaged+0x6e/0xc10 kthread+0xf9/0x130 ret_from_fork+0x3a/0x50 page last free stack trace: free_pcp_prepare+0x134/0x1e0 free_unref_page+0x18/0x90 khugepaged+0x7b/0xc10 kthread+0xf9/0x130 ret_from_fork+0x3a/0x50 Modules linked in: CPU: 3 PID: 271 Comm: bash Not tainted 5.3.0-rc4-2.g07a1a73-default+ #57 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0x85/0xc0 bad_page.cold+0xba/0xbf rmqueue_pcplist.isra.0+0x6c5/0x6d0 rmqueue+0x2d/0x810 get_page_from_freelist+0x191/0x380 __alloc_pages_nodemask+0x13c/0x2d0 __get_free_pages+0xd/0x30 __pud_alloc+0x2c/0x110 copy_page_range+0x4f9/0x630 dup_mmap+0x362/0x480 dup_mm+0x68/0x110 copy_process+0x19e1/0x1b40 _do_fork+0x73/0x310 __x64_sys_clone+0x75/0x80 do_syscall_64+0x6e/0x1e0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f10af854a10 ... Link: http://lkml.kernel.org/r/20190820131828.22684-5-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-23Merge tag 'pci-v5.4-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Enumeration: - Consolidate _HPP/_HPX stuff in pci-acpi.c and simplify it (Krzysztof Wilczynski) - Fix incorrect PCIe device types and remove dev->has_secondary_link to simplify code that deals with upstream/downstream ports (Mika Westerberg) - After suspend, restore Resizable BAR size bits correctly for 1MB BARs (Sumit Saxena) - Enable PCI_MSI_IRQ_DOMAIN support for RISC-V (Wesley Terpstra) Virtualization: - Add ACS quirks for iProc PAXB (Abhinav Ratna), Amazon Annapurna Labs (Ali Saidi) - Move sysfs SR-IOV functions to iov.c (Kelsey Skunberg) - Remove group write permissions from sysfs sriov_numvfs, sriov_drivers_autoprobe (Kelsey Skunberg) Hotplug: - Simplify pciehp indicator control (Denis Efremov) Peer-to-peer DMA: - Allow P2P DMA between root ports for whitelisted bridges (Logan Gunthorpe) - Whitelist some Intel host bridges for P2P DMA (Logan Gunthorpe) - DMA map P2P DMA requests that traverse host bridge (Logan Gunthorpe) Amazon Annapurna Labs host bridge driver: - Add DT binding and controller driver (Jonathan Chocron) Hyper-V host bridge driver: - Fix hv_pci_dev->pci_slot use-after-free (Dexuan Cui) - Fix PCI domain number collisions (Haiyang Zhang) - Use instance ID bytes 4 & 5 as PCI domain numbers (Haiyang Zhang) - Fix build errors on non-SYSFS config (Randy Dunlap) i.MX6 host bridge driver: - Limit DBI register length (Stefan Agner) Intel VMD host bridge driver: - Fix config addressing issues (Jon Derrick) Layerscape host bridge driver: - Add bar_fixed_64bit property to endpoint driver (Xiaowei Bao) - Add CONFIG_PCI_LAYERSCAPE_EP to build EP/RC drivers separately (Xiaowei Bao) Mediatek host bridge driver: - Add MT7629 controller support (Jianjun Wang) Mobiveil host bridge driver: - Fix CPU base address setup (Hou Zhiqiang) - Make "num-lanes" property optional (Hou Zhiqiang) Tegra host bridge driver: - Fix OF node reference leak (Nishka Dasgupta) - Disable MSI for root ports to work around design problem (Vidya Sagar) - Add Tegra194 DT binding and controller support (Vidya Sagar) - Add support for sideband pins and slot regulators (Vidya Sagar) - Add PIPE2UPHY support (Vidya Sagar) Misc: - Remove unused pci_block_cfg_access() et al (Kelsey Skunberg) - Unexport pci_bus_get(), etc (Kelsey Skunberg) - Hide PM, VC, link speed, ATS, ECRC, PTM constants and interfaces in the PCI core (Kelsey Skunberg) - Clean up sysfs DEVICE_ATTR() usage (Kelsey Skunberg) - Mark expected switch fall-through (Gustavo A. R. Silva) - Propagate errors for optional regulators and PHYs (Thierry Reding) - Fix kernel command line resource_alignment parameter issues (Logan Gunthorpe)" * tag 'pci-v5.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (112 commits) PCI: Add pci_irq_vector() and other stubs when !CONFIG_PCI arm64: tegra: Add PCIe slot supply information in p2972-0000 platform arm64: tegra: Add configuration for PCIe C5 sideband signals PCI: tegra: Add support to enable slot regulators PCI: tegra: Add support to configure sideband pins PCI: vmd: Fix shadow offsets to reflect spec changes PCI: vmd: Fix config addressing when using bus offsets PCI: dwc: Add validation that PCIe core is set to correct mode PCI: dwc: al: Add Amazon Annapurna Labs PCIe controller driver dt-bindings: PCI: Add Amazon's Annapurna Labs PCIe host bridge binding PCI: Add quirk to disable MSI-X support for Amazon's Annapurna Labs Root Port PCI/VPD: Prevent VPD access for Amazon's Annapurna Labs Root Port PCI: Add ACS quirk for Amazon Annapurna Labs root ports PCI: Add Amazon's Annapurna Labs vendor ID MAINTAINERS: Add PCI native host/endpoint controllers designated reviewer PCI: hv: Use bytes 4 and 5 from instance ID as the PCI domain numbers dt-bindings: PCI: tegra: Add PCIe slot supplies regulator entries dt-bindings: PCI: tegra: Add sideband pins configuration entries PCI: tegra: Add Tegra194 PCIe support PCI: Get rid of dev->has_secondary_link flag ...
2019-09-21Merge tag 'for-5.4/dm-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - crypto and DM crypt advances that allow the crypto API to reclaim implementation details that do not belong in DM crypt. The wrapper template for ESSIV generation that was factored out will also be used by fscrypt in the future. - Add root hash pkcs#7 signature verification to the DM verity target. - Add a new "clone" DM target that allows for efficient remote replication of a device. - Enhance DM bufio's cache to be tailored to each client based on use. Clients that make heavy use of the cache get more of it, and those that use less have reduced cache usage. - Add a new DM_GET_TARGET_VERSION ioctl to allow userspace to query the version number of a DM target (even if the associated module isn't yet loaded). - Fix invalid memory access in DM zoned target. - Fix the max_discard_sectors limit advertised by the DM raid target; it was mistakenly storing the limit in bytes rather than sectors. - Small optimizations and cleanups in DM writecache target. - Various fixes and cleanups in DM core, DM raid1 and space map portion of DM persistent data library. * tag 'for-5.4/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (22 commits) dm: introduce DM_GET_TARGET_VERSION dm bufio: introduce a global cache replacement dm bufio: remove old-style buffer cleanup dm bufio: introduce a global queue dm bufio: refactor adjust_total_allocated dm bufio: call adjust_total_allocated from __link_buffer and __unlink_buffer dm: add clone target dm raid: fix updating of max_discard_sectors limit dm writecache: skip writecache_wait for pmem mode dm stats: use struct_size() helper dm crypt: omit parsing of the encapsulated cipher dm crypt: switch to ESSIV crypto API template crypto: essiv - create wrapper template for ESSIV generation dm space map common: remove check for impossible sm_find_free() return value dm raid1: use struct_size() with kzalloc() dm writecache: optimize performance by sorting the blocks for writeback_all dm writecache: add unlikely for getting two block with same LBA dm writecache: remove unused member pointer in writeback_struct dm zoned: fix invalid memory access dm verity: add root hash pkcs#7 signature verification ...
2019-09-20Merge tag 'powerpc-5.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "This is a bit late, partly due to me travelling, and partly due to a power outage knocking out some of my test systems *while* I was travelling. - Initial support for running on a system with an Ultravisor, which is software that runs below the hypervisor and protects guests against some attacks by the hypervisor. - Support for building the kernel to run as a "Secure Virtual Machine", ie. as a guest capable of running on a system with an Ultravisor. - Some changes to our DMA code on bare metal, to allow devices with medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of DMA space. - Support for firmware assisted crash dumps on bare metal (powernv). - Two series fixing bugs in and refactoring our PCI EEH code. - A large series refactoring our exception entry code to use gas macros, both to make it more readable and also enable some future optimisations. As well as many cleanups and other minor features & fixups. Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand, Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar, Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm, Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu, Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom Lendacky, Vasant Hegde" * tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits) powerpc/mm/mce: Keep irqs disabled during lockless page table walk powerpc: Use ftrace_graph_ret_addr() when unwinding powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR ftrace: Look up the address of return_to_handler() using helpers powerpc: dump kernel log before carrying out fadump or kdump docs: powerpc: Add missing documentation reference powerpc/xmon: Fix output of XIVE IPI powerpc/xmon: Improve output of XIVE interrupts powerpc/mm/radix: remove useless kernel messages powerpc/fadump: support holes in kernel boot memory area powerpc/fadump: remove RMA_START and RMA_END macros powerpc/fadump: update documentation about option to release opalcore powerpc/fadump: consider f/w load area powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel powerpc/fadump: improve how crashed kernel's memory is reserved powerpc/fadump: consider reserved ranges while releasing memory powerpc/fadump: make crash memory ranges array allocation generic ...
2019-09-18Merge tag 'tty-5.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver updates from Greg KH: "Even in this age, people are still making new serial port silicon, why... Anyway, here's the TTY and Serial driver update for 5.4-rc1. Lots of changes in here for a number of embedded serial port devices that are being worked on because people really like to see those console logs... Other than that, nothing major here, no core tty changes that anyone should care about. All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (125 commits) serial: tegra: Add PIO mode support serial: tegra: report clk rate errors serial: tegra: add support to adjust baud rate serial: tegra: DT for Adjusted baud rates serial: tegra: add support to use 8 bytes trigger serial: tegra: set maximum num of uart ports to 8 serial: tegra: check for FIFO mode enabled status dt-binding: serial: tegra: add new chips serial: tegra: report error to upper tty layer serial: tegra: flush the RX fifo on frame error serial: tegra: avoid reg access when clk disabled serial: tegra: add support to ignore read serial: sprd: correct the wrong sequence of arguments dt-bindings: serial: Convert riscv,sifive-serial to json-schema serial: max310x: turn off transmitter before activating AutoCTS or auto transmitter flow control serial: max310x: Properly set flags in AutoCTS mode tty: serial: fix platform_no_drv_owner.cocci warnings dt-bindings: serial: Document Freescale LINFlexD UART serial: fsl_linflexuart: Update compatible string tty: n_gsm: avoid recursive locking with async port hangup ...
2019-09-17Merge tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: - Two NVMe pull requests: - ana log parse fix from Anton - nvme quirks support for Apple devices from Ben - fix missing bio completion tracing for multipath stack devices from Hannes and Mikhail - IP TOS settings for nvme rdma and tcp transports from Israel - rq_dma_dir cleanups from Israel - tracing for Get LBA Status command from Minwoo - Some nvme-tcp cleanups from Minwoo, Potnuri and Myself - Some consolidation between the fabrics transports for handling the CAP register - reset race with ns scanning fix for fabrics (move fabrics commands to a dedicated request queue with a different lifetime from the admin request queue)." - controller reset and namespace scan races fixes - nvme discovery log change uevent support - naming improvements from Keith - multiple discovery controllers reject fix from James - some regular cleanups from various people - Series fixing (and re-fixing) null_blk debug printing and nr_devices checks (André) - A few pull requests from Song, with fixes from Andy, Guoqing, Guilherme, Neil, Nigel, and Yufen. - REQ_OP_ZONE_RESET_ALL support (Chaitanya) - Bio merge handling unification (Christoph) - Pick default elevator correctly for devices with special needs (Damien) - Block stats fixes (Hou) - Timeout and support devices nbd fixes (Mike) - Series fixing races around elevator switching and device add/remove (Ming) - sed-opal cleanups (Revanth) - Per device weight support for BFQ (Fam) - Support for blk-iocost, a new model that can properly account cost of IO workloads. (Tejun) - blk-cgroup writeback fixes (Tejun) - paride queue init fixes (zhengbin) - blk_set_runtime_active() cleanup (Stanley) - Block segment mapping optimizations (Bart) - lightnvm fixes (Hans/Minwoo/YueHaibing) - Various little fixes and cleanups * tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-block: (186 commits) null_blk: format pr_* logs with pr_fmt null_blk: match the type of parameter nr_devices null_blk: do not fail the module load with zero devices block: also check RQF_STATS in blk_mq_need_time_stamp() block: make rq sector size accessible for block stats bfq: Fix bfq linkage error raid5: use bio_end_sector in r5_next_bio raid5: remove STRIPE_OPS_REQ_PENDING md: add feature flag MD_FEATURE_RAID0_LAYOUT md/raid0: avoid RAID0 data corruption due to layout confusion. raid5: don't set STRIPE_HANDLE to stripe which is in batch list raid5: don't increment read_errors on EILSEQ return nvmet: fix a wrong error status returned in error log page nvme: send discovery log page change events to userspace nvme: add uevent variables for controller devices nvme: enable aen regardless of the presence of I/O queues nvme-fabrics: allow discovery subsystems accept a kato nvmet: Use PTR_ERR_OR_ZERO() in nvmet_init_discovery() nvme: Remove redundant assignment of cq vector nvme: Assign subsys instance from first ctrl ...
2019-09-17Merge tag 'docs-5.4' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It's a somewhat calmer cycle for docs this time, as the churn of the mass RST conversion is happily mostly behind us. - A new document on reproducible builds. - We finally got around to zapping the documentation for hardware support that was removed in 2004; one doesn't want to rush these things. - The usual assortment of fixes, typo corrections, etc" * tag 'docs-5.4' of git://git.lwn.net/linux: (67 commits) Documentation: kbuild: Add document about reproducible builds docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi] Documentation: Add "earlycon=sbi" to the admin guide doc:lock: remove reference to clever use of read-write lock devices.txt: improve entry for comedi (char major 98) docs: mtd: Update spi nor reference driver doc: arm64: fix grammar dtb placed in no attributes region Documentation: sysrq: don't recommend 'S' 'U' before 'B' mailmap: Update email address for Quentin Perret docs: ftrace: clarify when tracing is disabled by the trace file docs: process: fix broken link Documentation/arm/samsung-s3c24xx: Remove stray U+FEFF character to fix title Documentation/arm/sa1100/assabet: Fix 'make assabet_defconfig' command Documentation/arm/sa1100: Remove some obsolete documentation docs/zh_CN: update Chinese howto.rst for latexdocs making Documentation: virt: Fix broken reference to virt tree's index docs: Fix typo on pull requests guide kernel-doc: Allow anonymous enum Documentation: sphinx: Don't parse socket() as identifier reference Documentation: sphinx: Add missing comma to list of strings ...