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* x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale DataPawan Gupta2022-06-161-0/+1
| | | | | | | | | | | | | | commit 8d50cdf8b8341770bc6367bce40c0c1bb0e1d5b3 upstream Add the sysfs reporting file for Processor MMIO Stale Data vulnerability. It exposes the vulnerability and mitigation state similar to the existing files for the other hardware vulnerabilities. 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> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/speculation/mmio: Add mitigation for Processor MMIO Stale DataPawan Gupta2022-06-161-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8cb861e9e3c9a55099ad3d08e1a3b653d29c33ca upstream Processor MMIO Stale Data is a class of vulnerabilities that may expose data after an MMIO operation. For details please refer to Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst. These vulnerabilities are broadly categorized as: Device Register Partial Write (DRPW): Some endpoint MMIO registers incorrectly handle writes that are smaller than the register size. Instead of aborting the write or only copying the correct subset of bytes (for example, 2 bytes for a 2-byte write), more bytes than specified by the write transaction may be written to the register. On some processors, this may expose stale data from the fill buffers of the core that created the write transaction. Shared Buffers Data Sampling (SBDS): After propagators may have moved data around the uncore and copied stale data into client core fill buffers, processors affected by MFBDS can leak data from the fill buffer. Shared Buffers Data Read (SBDR): It is similar to Shared Buffer Data Sampling (SBDS) except that the data is directly read into the architectural software-visible state. An attacker can use these vulnerabilities to extract data from CPU fill buffers using MDS and TAA methods. Mitigate it by clearing the CPU fill buffers using the VERW instruction before returning to a user or a guest. On CPUs not affected by MDS and TAA, user application cannot sample data from CPU fill buffers using MDS or TAA. A guest with MMIO access can still use DRPW or SBDR to extract data architecturally. Mitigate it with VERW instruction to clear fill buffers before VMENTER for MMIO capable guests. Add a kernel parameter mmio_stale_data={off|full|full,nosmt} to control the mitigation. 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> [cascardo: arch/x86/kvm/vmx.c has been moved] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: Add documentation for Processor MMIO Stale DataPawan Gupta2022-06-162-0/+247
| | | | | | | | | | | | | commit 4419470191386456e0b8ed4eb06a70b0021798a6 upstream Add the admin guide for Processor MMIO stale data vulnerabilities. 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> [cascardo: index.rst conflict fixup] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ata: libata-transport: fix {dma|pio|xfer}_mode sysfs filesSergey Shtylyov2022-06-141-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 72aad489f992871e908ff6d9055b26c6366fb864 upstream. The {dma|pio}_mode sysfs files are incorrectly documented as having a list of the supported DMA/PIO transfer modes, while the corresponding fields of the *struct* ata_device hold the transfer mode IDs, not masks. To match these docs, the {dma|pio}_mode (and even xfer_mode!) sysfs files are handled by the ata_bitfield_name_match() macro which leads to reading such kind of nonsense from them: $ cat /sys/class/ata_device/dev3.0/pio_mode XFER_UDMA_7, XFER_UDMA_6, XFER_UDMA_5, XFER_UDMA_4, XFER_MW_DMA_4, XFER_PIO_6, XFER_PIO_5, XFER_PIO_4, XFER_PIO_3, XFER_PIO_2, XFER_PIO_1, XFER_PIO_0 Using the correct ata_bitfield_name_search() macro fixes that: $ cat /sys/class/ata_device/dev3.0/pio_mode XFER_PIO_4 While fixing the file documentation, somewhat reword the {dma|pio}_mode file doc and add a note about being mostly useful for PATA devices to the xfer_mode file doc... Fixes: d9027470b886 ("[libata] Add ATA transport class") Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru> Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dt-bindings: gpio: altera: correct interrupt-cellsDinh Nguyen2022-06-141-2/+3
| | | | | | | | | | | commit 3a21c3ac93aff7b4522b152399df8f6a041df56d upstream. update documentation to correctly state the interrupt-cells to be 2. Cc: stable@vger.kernel.org Fixes: 4fd9bbc6e071 ("drivers/gpio: Altera soft IP GPIO driver devicetree binding") Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* docs/conf.py: Cope with removal of language=None in Sphinx 5.0.0Akira Yokosawa2022-06-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 627f01eab93d8671d4e4afee9b148f9998d20e7c upstream. One of the changes in Sphinx 5.0.0 [1] says [sic]: 5.0.0 final - #10474: language does not accept None as it value. The default value of language becomes to 'en' now. [1]: https://www.sphinx-doc.org/en/master/changes.html#release-5-0-0-released-may-30-2022 It results in a new warning from Sphinx 5.0.0 [sic]: WARNING: Invalid configuration value found: 'language = None'. Update your configuration to a valid langauge code. Falling back to 'en' (English). Silence the warning by using 'en'. It works with all the Sphinx versions required for building kernel documentation (1.7.9 or later). Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/bd0c2ddc-2401-03cb-4526-79ca664e1cbe@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* arm64: Add silicon-errata.txt entry for ARM erratum 1188873Marc Zyngier2022-04-121-0/+1
| | | | | | | | | | | | commit e03a4e5bb7430f9294c12f02c69eb045d010e942 upstream. Document that we actually work around ARM erratum 1188873 Fixes: 95b861a4a6d9 ("arm64: arch_timer: Add workaround for ARM erratum 1188873") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* clocksource/drivers/arm_arch_timer: Remove fsl-a008585 parameterDing Tianhong2022-04-121-9/+0
| | | | | | | | | | | | | | | | | commit 5444ea6a7f46276876e94ecf8d44615af1ef22f7 upstream. Having a command line option to flip the errata handling for a particular erratum is a little bit unusual, and it's vastly superior to pass this in the DT. By common consensus, it's best to kill off the command line parameter. Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> [Mark: split patch, reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/speculation: Update link to AMD speculation whitepaperKim Phillips2022-03-111-3/+3
| | | | | | | | | | | | | commit e9b6013a7ce31535b04b02ba99babefe8a8599fa upstream. Update the link to the "Software Techniques for Managing Speculation on AMD Processors" whitepaper. Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> [bwh: Backported to 4.9: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation/hw-vuln: Update spectre docPeter Zijlstra2022-03-112-15/+35
| | | | | | | | | | | | | | | | | commit 5ad3eb1132453b9795ce5fd4572b1c18b292cca9 upstream. Update the doc with the new fun. [ bp: Massage commit message. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> [fllinden@amazon.com: backported to 4.19] Signed-off-by: Frank van der Linden <fllinden@amazon.com> [bwh: Backported to 4.9: adjust filenames] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: refer to config RANDOMIZE_BASE for kernel address-space ↵Lukas Bulwahn2022-03-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | randomization commit 82ca67321f55a8d1da6ac3ed611da3c32818bb37 upstream. The config RANDOMIZE_SLAB does not exist, the authors probably intended to refer to the config RANDOMIZE_BASE, which provides kernel address-space randomization. They probably just confused SLAB with BASE (these two four-letter words coincidentally share three common letters), as they also point out the config SLAB_FREELIST_RANDOM as further randomization within the same sentence. Fix the reference of the config for kernel address-space randomization to the config that provides that. Fixes: 6e88559470f5 ("Documentation: Add section about CPU vulnerabilities for Spectre") Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Link: https://lore.kernel.org/r/20211230171940.27558-1-lukas.bulwahn@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net> [bwh: Backported to 4.9: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: Add swapgs description to the Spectre v1 documentationJosh Poimboeuf2022-03-111-8/+80
| | | | | | | | | | | | | commit 4c92057661a3412f547ede95715641d7ee16ddac upstream. Add documentation to the Spectre document about the new swapgs variant of Spectre v1. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [bwh: Backported to 4.9: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: Add section about CPU vulnerabilities for SpectreTim Chen2022-03-112-0/+698
| | | | | | | | | | | | | | | | | | | | | | | | | commit 6e88559470f581741bcd0f2794f9054814ac9740 upstream. Add documentation for Spectre vulnerability and the mitigation mechanisms: - Explain the problem and risks - Document the mitigation mechanisms - Document the command line controls - Document the sysfs files Co-developed-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Co-developed-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> [bwh: Backported to 4.9: - Drop chnages in spec_ctrl.rst, which is a plain-text document here - Adjust filenames and references to spec_ctrl.rst] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* bpf: Add kconfig knob for disabling unpriv bpf by defaultDaniel Borkmann2022-02-161-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | commit 08389d888287c3823f80b0216766b71e17f0aba5 upstream. Add a kconfig knob which allows for unprivileged bpf to be disabled by default. If set, the knob sets /proc/sys/kernel/unprivileged_bpf_disabled to value of 2. This still allows a transition of 2 -> {0,1} through an admin. Similarly, this also still keeps 1 -> {1} behavior intact, so that once set to permanently disabled, it cannot be undone aside from a reboot. We've also added extra2 with max of 2 for the procfs handler, so that an admin still has a chance to toggle between 0 <-> 2. Either way, as an additional alternative, applications can make use of CAP_BPF that we added a while ago. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/74ec548079189e4e4dffaeb42b8987bb3c852eee.1620765074.git.daniel@iogearbox.net [fllinden@amazon.com: backported to 4.9] Signed-off-by: Frank van der Linden <fllinden@amazon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: X86: MMU: Use the correct inherited permissions to get shadow pageLai Jiangshan2022-01-291-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b1bd5cba3306691c771d558e94baa73e8b0b96b7 upstream. When computing the access permissions of a shadow page, use the effective permissions of the walk up to that point, i.e. the logic AND of its parents' permissions. Two guest PxE entries that point at the same table gfn need to be shadowed with different shadow pages if their parents' permissions are different. KVM currently uses the effective permissions of the last non-leaf entry for all non-leaf entries. Because all non-leaf SPTEs have full ("uwx") permissions, and the effective permissions are recorded only in role.access and merged into the leaves, this can lead to incorrect reuse of a shadow page and eventually to a missing guest protection page fault. For example, here is a shared pagetable: pgd[] pud[] pmd[] virtual address pointers /->pmd1(u--)->pte1(uw-)->page1 <- ptr1 (u--) /->pud1(uw-)--->pmd2(uw-)->pte2(uw-)->page2 <- ptr2 (uw-) pgd-| (shared pmd[] as above) \->pud2(u--)--->pmd1(u--)->pte1(uw-)->page1 <- ptr3 (u--) \->pmd2(uw-)->pte2(uw-)->page2 <- ptr4 (u--) pud1 and pud2 point to the same pmd table, so: - ptr1 and ptr3 points to the same page. - ptr2 and ptr4 points to the same page. (pud1 and pud2 here are pud entries, while pmd1 and pmd2 here are pmd entries) - First, the guest reads from ptr1 first and KVM prepares a shadow page table with role.access=u--, from ptr1's pud1 and ptr1's pmd1. "u--" comes from the effective permissions of pgd, pud1 and pmd1, which are stored in pt->access. "u--" is used also to get the pagetable for pud1, instead of "uw-". - Then the guest writes to ptr2 and KVM reuses pud1 which is present. The hypervisor set up a shadow page for ptr2 with pt->access is "uw-" even though the pud1 pmd (because of the incorrect argument to kvm_mmu_get_page in the previous step) has role.access="u--". - Then the guest reads from ptr3. The hypervisor reuses pud1's shadow pmd for pud2, because both use "u--" for their permissions. Thus, the shadow pmd already includes entries for both pmd1 and pmd2. - At last, the guest writes to ptr4. This causes no vmexit or pagefault, because pud1's shadow page structures included an "uw-" page even though its role.access was "u--". Any kind of shared pagetable might have the similar problem when in virtual machine without TDP enabled if the permissions are different from different ancestors. In order to fix the problem, we change pt->access to be an array, and any access in it will not include permissions ANDed from child ptes. The test code is: https://lore.kernel.org/kvm/20210603050537.19605-1-jiangshanlai@gmail.com/ Remember to test it with TDP disabled. The problem had existed long before the commit 41074d07c78b ("KVM: MMU: Fix inherited permissions for emulated guest pte updates"), and it is hard to find which is the culprit. So there is no fixes tag here. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Message-Id: <20210603052455.21023-1-jiangshanlai@gmail.com> Cc: stable@vger.kernel.org Fixes: cea0f0e7ea54 ("[PATCH] KVM: MMU: Shadow page table caching") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 4.9: - Keep passing vcpu argument to gpte_access functions - Adjust filenames, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* rbtree: cache leftmost node internallyDavidlohr Bueso2022-01-271-0/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit cd9e61ed1eebbcd5dfad59475d41ec58d9b64b6a upstream. Patch series "rbtree: Cache leftmost node internally", v4. A series to extending rbtrees to internally cache the leftmost node such that we can have fast overlap check optimization for all interval tree users[1]. The benefits of this series are that: (i) Unify users that do internal leftmost node caching. (ii) Optimize all interval tree users. (iii) Convert at least two new users (epoll and procfs) to the new interface. This patch (of 16): Red-black tree semantics imply that nodes with smaller or greater (or equal for duplicates) keys always be to the left and right, respectively. For the kernel this is extremely evident when considering our rb_first() semantics. Enabling lookups for the smallest node in the tree in O(1) can save a good chunk of cycles in not having to walk down the tree each time. To this end there are a few core users that explicitly do this, such as the scheduler and rtmutexes. There is also the desire for interval trees to have this optimization allowing faster overlap checking. This patch introduces a new 'struct rb_root_cached' which is just the root with a cached pointer to the leftmost node. The reason why the regular rb_root was not extended instead of adding a new structure was that this allows the user to have the choice between memory footprint and actual tree performance. The new wrappers on top of the regular rb_root calls are: - rb_first_cached(cached_root) -- which is a fast replacement for rb_first. - rb_insert_color_cached(node, cached_root, new) - rb_erase_cached(node, cached_root) In addition, augmented cached interfaces are also added for basic insertion and deletion operations; which becomes important for the interval tree changes. With the exception of the inserts, which adds a bool for updating the new leftmost, the interfaces are kept the same. To this end, porting rb users to the cached version becomes really trivial, and keeping current rbtree semantics for users that don't care about the optimization requires zero overhead. Link: http://lkml.kernel.org/r/20170719014603.19029-2-dave@stgolabs.net Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* bonding: fix ad_actor_system option setting to defaultFernando Fernandez Mancera2021-12-291-5/+6
| | | | | | | | | | | | | | | | | | [ Upstream commit 1c15b05baea71a5ff98235783e3e4ad227760876 ] When 802.3ad bond mode is configured the ad_actor_system option is set to "00:00:00:00:00:00". But when trying to set the all-zeroes MAC as actors' system address it was failing with EINVAL. An all-zeroes ethernet address is valid, only multicast addresses are not valid values. Fixes: 171a42c38c6e ("bonding: add netlink support for sys prio, actor sys mac, and port key") Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net> Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com> Link: https://lore.kernel.org/r/20211221111345.2462-1-ffmancera@riseup.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* regulator: dt-bindings: samsung,s5m8767: correct ↵Krzysztof Kozlowski2021-11-261-1/+1
| | | | | | | | | | | | | | | | | s5m8767,pmic-buck-default-dvs-idx property commit a7fda04bc9b6ad9da8e19c9e6e3b1dab773d068a upstream. The driver was always parsing "s5m8767,pmic-buck-default-dvs-idx", not "s5m8767,pmic-buck234-default-dvs-idx". Cc: <stable@vger.kernel.org> Fixes: 26aec009f6b6 ("regulator: add device tree support for s5m8767") Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Acked-by: Rob Herring <robh@kernel.org> Message-Id: <20211008113723.134648-3-krzysztof.kozlowski@canonical.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* regulator: s5m8767: do not use reset value as DVS voltage if GPIO DVS is ↵Krzysztof Kozlowski2021-11-261-13/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | disabled commit b16bef60a9112b1e6daf3afd16484eb06e7ce792 upstream. The driver and its bindings, before commit 04f9f068a619 ("regulator: s5m8767: Modify parsing method of the voltage table of buck2/3/4") were requiring to provide at least one safe/default voltage for DVS registers if DVS GPIO is not being enabled. IOW, if s5m8767,pmic-buck2-uses-gpio-dvs is missing, the s5m8767,pmic-buck2-dvs-voltage should still be present and contain one voltage. This requirement was coming from driver behavior matching this condition (none of DVS GPIO is enabled): it was always initializing the DVS selector pins to 0 and keeping the DVS enable setting at reset value (enabled). Therefore if none of DVS GPIO is enabled in devicetree, driver was configuring the first DVS voltage for buck[234]. Mentioned commit 04f9f068a619 ("regulator: s5m8767: Modify parsing method of the voltage table of buck2/3/4") broke it because DVS voltage won't be parsed from devicetree if DVS GPIO is not enabled. After the change, driver will configure bucks to use the register reset value as voltage which might have unpleasant effects. Fix this by relaxing the bindings constrain: if DVS GPIO is not enabled in devicetree (therefore DVS voltage is also not parsed), explicitly disable it. Cc: <stable@vger.kernel.org> Fixes: 04f9f068a619 ("regulator: s5m8767: Modify parsing method of the voltage table of buck2/3/4") Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Acked-by: Rob Herring <robh@kernel.org> Message-Id: <20211008113723.134648-2-krzysztof.kozlowski@canonical.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dt-bindings: mtd: gpmc: Fix the ECC bytes vs. OOB bytes equationMiquel Raynal2021-09-221-1/+1
| | | | | | | | | | | | | | | | | | | [ Upstream commit 778cb8e39f6ec252be50fc3850d66f3dcbd5dd5a ] "PAGESIZE / 512" is the number of ECC chunks. "ECC_BYTES" is the number of bytes needed to store a single ECC code. "2" is the space reserved by the bad block marker. "2 + (PAGESIZE / 512) * ECC_BYTES" should of course be lower or equal than the total number of OOB bytes, otherwise it won't fit. Fix the equation by substituting s/>=/<=/. Suggested-by: Ryan J. Barnett <ryan.barnett@collins.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/linux-mtd/20210610143945.3504781-1-miquel.raynal@bootlin.com Signed-off-by: Sasha Levin <sashal@kernel.org>
* locks: print a warning when mount fails due to lack of "mand" supportJeff Layton2021-08-261-0/+10
| | | | | | | | | | | | | | | | | | | | | | [ Upstream commit df2474a22c42ce419b67067c52d71da06c385501 ] Since 9e8925b67a ("locks: Allow disabling mandatory locking at compile time"), attempts to mount filesystems with "-o mand" will fail. Unfortunately, there is no other indiciation of the reason for the failure. Change how the function is defined for better readability. When CONFIG_MANDATORY_FILE_LOCKING is disabled, printk a warning when someone attempts to mount with -o mand. Also, add a blurb to the mandatory-locking.txt file to explain about the "mand" option, and the behavior one should expect when it is disabled. Reported-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* tweewide: Fix most Shebang linesFinn Behrens2021-06-035-5/+5
| | | | | | | | | | | | | | commit c25ce589dca10d64dde139ae093abc258a32869c upstream. Change every shebang which does not need an argument to use /usr/bin/env. This is needed as not every distro has everything under /usr/bin, sometimes not even bash. Signed-off-by: Finn Behrens <me@kloenk.de> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> [nicolas@fjasle.eu: update contexts for v4.9, adapt for old scripts] Signed-off-by: Nicolas Schier <nicolas@fjasle.eu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs outputJoe Perches2021-03-071-5/+3
| | | | | | | | | | | | | | | | | | | | | | | commit 2efc459d06f1630001e3984854848a5647086232 upstream. Output defects can exist in sysfs content using sprintf and snprintf. sprintf does not know the PAGE_SIZE maximum of the temporary buffer used for outputting sysfs content and it's possible to overrun the PAGE_SIZE buffer length. Add a generic sysfs_emit function that knows that the size of the temporary buffer and ensures that no overrun is done. Add a generic sysfs_emit_at function that can be used in multiple call situations that also ensures that no overrun is done. Validate the output buffer argument to be page aligned. Validate the offset len argument to be within the PAGE_SIZE buf. Signed-off-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/884235202216d464d61ee975f7465332c86f76b2.1600285923.git.joe@perches.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dt-bindings: net: correct interrupt flags in examplesKrzysztof Kozlowski2020-12-112-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 4d521943f76bd0d1e68ea5e02df7aadd30b2838a ] GPIO_ACTIVE_x flags are not correct in the context of interrupt flags. These are simple defines so they could be used in DTS but they will not have the same meaning: 1. GPIO_ACTIVE_HIGH = 0 = IRQ_TYPE_NONE 2. GPIO_ACTIVE_LOW = 1 = IRQ_TYPE_EDGE_RISING Correct the interrupt flags, assuming the author of the code wanted same logical behavior behind the name "ACTIVE_xxx", this is: ACTIVE_LOW => IRQ_TYPE_LEVEL_LOW ACTIVE_HIGH => IRQ_TYPE_LEVEL_HIGH Fixes: a1a8b4594f8d ("NFC: pn544: i2c: Add DTS Documentation") Fixes: 6be88670fc59 ("NFC: nxp-nci_i2c: Add I2C support to NXP NCI driver") Fixes: e3b329221567 ("dt-bindings: can: tcan4x5x: Update binding to use interrupt property") Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for tcan4x5x.txt Link: https://lore.kernel.org/r/20201026153620.89268-1-krzk@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64s: flush L1D after user accessesNicholas Piggin2020-11-221-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/64s: flush L1D on kernel entryNicholas Piggin2020-11-221-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xen/events: defer eoi in case of excessive number of eventsJuergen Gross2020-11-181-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e99502f76271d6bc4e374fe368c50c67a1fd3070 upstream. In case rogue guests are sending events at high frequency it might happen that xen_evtchn_do_upcall() won't stop processing events in dom0. As this is done in irq handling a crash might be the result. In order to avoid that, delay further inter-domain events after some time in xen_evtchn_do_upcall() by forcing eoi processing into a worker on the same cpu, thus inhibiting new events coming in. The time after which eoi processing is to be delayed is configurable via a new module parameter "event_loop_timeout" which specifies the maximum event loop time in jiffies (default: 2, the value was chosen after some tests showing that a value of 2 was the lowest with an only slight drop of dom0 network throughput while multiple guests performed an event storm). How long eoi processing will be delayed can be specified via another parameter "event_eoi_delay" (again in jiffies, default 10, again the value was chosen after testing with different delay values). This is part of XSA-332. Cc: stable@vger.kernel.org Reported-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* icmp: randomize the global rate limiterEric Dumazet2020-10-291-1/+3
| | | | | | | | | | | | | | | | | [ Upstream commit b38e7819cae946e2edf869e604af1e65a5d241c5 ] Keyu Man reported that the ICMP rate limiter could be used by attackers to get useful signal. Details will be provided in an upcoming academic publication. Our solution is to add some noise, so that the attackers no longer can get help from the predictable token bucket limiter. Fixes: 4cdf507d5452 ("icmp: add a global rate limitation") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Keyu Man <kman001@ucr.edu> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ata: make qc_prep return ata_completion_errorsJiri Slaby2020-10-011-1/+1
| | | | | | | | | | | | | | | | | commit 95364f36701e62dd50eee91e1303187fd1a9f567 upstream. In case a driver wants to return an error from qc_prep, return enum ata_completion_errors. sata_mv is one of those drivers -- see the next patch. Other drivers return the newly defined AC_ERR_OK. [v2] use enum ata_completion_errors and AC_ERR_OK. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-ide@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dt-bindings: sound: wm8994: Correct required supplies based on actual ↵Krzysztof Kozlowski2020-10-011-6/+12
| | | | | | | | | | | | | | | | | implementaion [ Upstream commit 8c149b7d75e53be47648742f40fc90d9fc6fa63a ] The required supplies in bindings were actually not matching implementation making the bindings incorrect and misleading. The Linux kernel driver requires all supplies to be present. Also for wlf,wm8994 uses just DBVDD-supply instead of DBVDDn-supply (n: <1,3>). Reported-by: Jonathan Bakker <xc-racer2@live.ca> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Link: https://lore.kernel.org/r/20200501133534.6706-1-krzk@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* affs: fix basic permission bits to actually workMax Staudt2020-09-121-6/+10
| | | | | | | | | | | | | | | | | | | [ Upstream commit d3a84a8d0dde4e26bc084b36ffcbdc5932ac85e2 ] The basic permission bits (protection bits in AmigaOS) have been broken in Linux' AFFS - it would only set bits, but never delete them. Also, contrary to the documentation, the Archived bit was not handled. Let's fix this for good, and set the bits such that Linux and classic AmigaOS can coexist in the most peaceful manner. Also, update the documentation to represent the current state of things. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Max Staudt <max@enpas.org> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* iio: improve IIO_CONCENTRATION channel type descriptionTomasz Duszynski2020-08-211-1/+2
| | | | | | | | | | | | | | | | | | [ Upstream commit df16c33a4028159d1ba8a7061c9fa950b58d1a61 ] IIO_CONCENTRATION together with INFO_RAW specifier is used for reporting raw concentrations of pollutants. Raw value should be meaningless before being properly scaled. Because of that description shouldn't mention raw value unit whatsoever. Fix this by rephrasing existing description so it follows conventions used throughout IIO ABI docs. Fixes: 8ff6b3bc94930 ("iio: chemical: Add IIO_CONCENTRATION channel type") Signed-off-by: Tomasz Duszynski <tomasz.duszynski@octakon.com> Acked-by: Matt Ranostay <matt.ranostay@konsulko.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* media: dvb_frontend: fix return values for FE_SET_PROPERTYMauro Carvalho Chehab2020-06-301-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 259a41d9ae8f3689742267f340ad2b159d00b302 upstream There are several problems with regards to the return of FE_SET_PROPERTY. The original idea were to return per-property return codes via tvp->result field, and to return an updated set of values. However, that never worked. What's actually implemented is: - the FE_SET_PROPERTY implementation doesn't call .get_frontend callback in order to get the actual parameters after return; - the tvp->result field is only filled if there's no error. So, it is always filled with zero; - FE_SET_PROPERTY doesn't call memdup_user() nor any other copy_to_user() function. So, any changes to the properties will be lost; - FE_SET_PROPERTY is declared as a write-only ioctl (IOW). While we could fix the above, it could cause regressions. So, let's just assume what the code really does, updating the documentation accordingly and removing the logic that would update the discarded tvp->result. Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dt-bindings: display: mediatek: control dpi pins mode to avoid leakageJitao Shi2020-06-201-0/+6
| | | | | | | | | | | | | [ Upstream commit b0ff9b590733079f7f9453e5976a9dd2630949e3 ] Add property "pinctrl-names" to swap pin mode between gpio and dpi mode. Set the dpi pins to gpio mode and output-low to avoid leakage current when dpi disabled. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com> Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exitJon Doron2020-06-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit f7d31e65368aeef973fab788aa22c4f1d5a6af66 ] The problem the patch is trying to address is the fact that 'struct kvm_hyperv_exit' has different layout on when compiling in 32 and 64 bit modes. In 64-bit mode the default alignment boundary is 64 bits thus forcing extra gaps after 'type' and 'msr' but in 32-bit mode the boundary is at 32 bits thus no extra gaps. This is an issue as even when the kernel is 64 bit, the userspace using the interface can be both 32 and 64 bit but the same 32 bit userspace has to work with 32 bit kernel. The issue is fixed by forcing the 64 bit layout, this leads to ABI change for 32 bit builds and while we are obviously breaking '32 bit userspace with 32 bit kernel' case, we're fixing the '32 bit userspace with 64 bit kernel' one. As the interface has no (known) users and 32 bit KVM is rather baroque nowadays, this seems like a reasonable decision. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Jon Doron <arilou@gmail.com> Message-Id: <20200424113746.3473563-2-arilou@gmail.com> Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* x86/speculation: Add Ivy Bridge to affected listJosh Poimboeuf2020-06-111-3/+4
| | | | | | | | | | commit 3798cc4d106e91382bfe016caa2edada27c2bb3f upstream Make the docs match the code. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/speculation: Add SRBDS vulnerability and mitigation documentationMark Gross2020-06-112-1/+150
| | | | | | | | | | | | | | | commit 7222a1b5b87417f22265c92deea76a6aecd0fb0f upstream Add documentation for the SRBDS vulnerability and its mitigation. [ bp: Massage. jpoimboe: sysfs table strings. ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigationMark Gross2020-06-112-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream SRBDS is an MDS-like speculative side channel that can leak bits from the random number generator (RNG) across cores and threads. New microcode serializes the processor access during the execution of RDRAND and RDSEED. This ensures that the shared buffer is overwritten before it is released for reuse. While it is present on all affected CPU models, the microcode mitigation is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the cases where TSX is not supported or has been disabled with TSX_CTRL. The mitigation is activated by default on affected processors and it increases latency for RDRAND and RDSEED instructions. Among other effects this will reduce throughput from /dev/urandom. * Enable administrator to configure the mitigation off when desired using either mitigations=off or srbds=off. * Export vulnerability status via sysfs * Rename file-scoped macros to apply for non-whitelist table initializations. [ bp: Massage, - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g, - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in, - flip check in cpu_set_bug_bits() to save an indentation level, - reflow comments. jpoimboe: s/Mitigated/Mitigation/ in user-visible strings tglx: Dropped the fused off magic for now ] Signed-off-by: Mark Gross <mgross@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: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*Asbjørn Sloth Tønnesen2020-05-271-4/+4
| | | | | | | | | | | | | commit 47c3e7783be4e142b861d34b5c2e223330b05d8a upstream. PPPOL2TP_MSG_* and L2TP_MSG_* are duplicates, and are being used interchangeably in the kernel, so let's standardize on L2TP_MSG_* internally, and keep PPPOL2TP_MSG_* defined in UAPI for compatibility. Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Giuliano Procida <gprocida@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dt-bindings: net: FMan erratum A050385Madalin Bucur2020-04-021-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 26d5bb9e4c4b541c475751e015072eb2cbf70d15 ] FMAN DMA read or writes under heavy traffic load may cause FMAN internal resource leak; thus stopping further packet processing. The FMAN internal queue can overflow when FMAN splits single read or write transactions into multiple smaller transactions such that more than 17 AXI transactions are in flight from FMAN to interconnect. When the FMAN internal queue overflows, it can stall further packet processing. The issue can occur with any one of the following three conditions: 1. FMAN AXI transaction crosses 4K address boundary (Errata A010022) 2. FMAN DMA address for an AXI transaction is not 16 byte aligned, i.e. the last 4 bits of an address are non-zero 3. Scatter Gather (SG) frames have more than one SG buffer in the SG list and any one of the buffers, except the last buffer in the SG list has data size that is not a multiple of 16 bytes, i.e., other than 16, 32, 48, 64, etc. With any one of the above three conditions present, there is likelihood of stalled FMAN packet processing, especially under stress with multiple ports injecting line-rate traffic. To avoid situations that stall FMAN packet processing, all of the above three conditions must be avoided; therefore, configure the system with the following rules: 1. Frame buffers must not span a 4KB address boundary, unless the frame start address is 256 byte aligned 2. All FMAN DMA start addresses (for example, BMAN buffer address, FD[address] + FD[offset]) are 16B aligned 3. SG table and buffer addresses are 16B aligned and the size of SG buffers are multiple of 16 bytes, except for the last SG buffer that can be of any size. Additional workaround notes: - Address alignment of 64 bytes is recommended for maximally efficient system bus transactions (although 16 byte alignment is sufficient to avoid the stall condition) - To support frame sizes that are larger than 4K bytes, there are two options: 1. Large single buffer frames that span a 4KB page boundary can be converted into SG frames to avoid transaction splits at the 4KB boundary, 2. Align the large single buffer to 256B address boundaries, ensure that the frame address plus offset is 256B aligned. - If software generated SG frames have buffers that are unaligned and with random non-multiple of 16 byte lengths, before transmitting such frames via FMAN, frames will need to be copied into a new single buffer or multiple buffer SG frame that is compliant with the three rules listed above. Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ACPI: watchdog: Allow disabling WDAT at bootJean Delvare2020-03-201-0/+4
| | | | | | | | | | | | [ Upstream commit 3f9e12e0df012c4a9a7fd7eb0d3ae69b459d6b2c ] In case the WDAT interface is broken, give the user an option to ignore it to let a native driver bind to the watchdog device instead. Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* cifs_atomic_open(): fix double-put on late allocation failureAl Viro2020-03-201-0/+7
| | | | | | | | | | | | | | | | | | | | | commit d9a9f4849fe0c9d560851ab22a85a666cddfdd24 upstream. several iterations of ->atomic_open() calling conventions ago, we used to need fput() if ->atomic_open() failed at some point after successful finish_open(). Now (since 2016) it's not needed - struct file carries enough state to make fput() work regardless of the point in struct file lifecycle and discarding it on failure exits in open() got unified. Unfortunately, I'd missed the fact that we had an instance of ->atomic_open() (cifs one) that used to need that fput(), as well as the stale comment in finish_open() demanding such late failure handling. Trivially fixed... Fixes: fe9ec8291fca "do_last(): take fput() on error after opening to out:" Cc: stable@kernel.org # v4.7+ Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: Document arm64 kpti controlJeremy Linton2020-01-291-0/+6
| | | | | | | | | | | | | | | | commit de19055564c8f8f9d366f8db3395836da0b2176c upstream. For a while Arm64 has been capable of force enabling or disabling the kpti mitigations. Lets make sure the documentation reflects that. Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> [florian: patch the correct file] Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mei: fix modalias documentationAlexander Usyskin2020-01-231-1/+1
| | | | | | | | | | | | | | commit 73668309215285366c433489de70d31362987be9 upstream. mei client bus added the client protocol version to the device alias, but ABI documentation was not updated. Fixes: b26864cad1c9 (mei: bus: add client protocol version to the device alias) Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Link: https://lore.kernel.org/r/20191008005735.12707-1-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* rtc: dt-binding: abx80x: fix resistance scaleBaruch Siach2019-12-211-1/+1
| | | | | | | | | | [ Upstream commit 73852e56827f5cb5db9d6e8dd8191fc2f2e8f424 ] The abracon,tc-resistor property value is in kOhm. Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* HID: doc: fix wrong data structure reference for UHID_OUTPUTPeter Hutterer2019-12-051-1/+1
| | | | | | | | [ Upstream commit 46b14eef59a8157138dc02f916a7f97c73b3ec53 ] Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Sasha Levin <sashal@kernel.org>
* x86/speculation: Fix incorrect MDS/TAA mitigation statusWaiman Long2019-11-283-3/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 64870ed1b12e235cfca3f6c6da75b542c973ff78 upstream. For MDS vulnerable processors with TSX support, enabling either MDS or TAA mitigations will enable the use of VERW to flush internal processor buffers at the right code path. IOW, they are either both mitigated or both not. However, if the command line options are inconsistent, the vulnerabilites sysfs files may not report the mitigation status correctly. For example, with only the "mds=off" option: vulnerabilities/mds:Vulnerable; SMT vulnerable vulnerabilities/tsx_async_abort:Mitigation: Clear CPU buffers; SMT vulnerable The mds vulnerabilities file has wrong status in this case. Similarly, the taa vulnerability file will be wrong with mds mitigation on, but taa off. Change taa_select_mitigation() to sync up the two mitigation status and have them turned off if both "mds=off" and "tsx_async_abort=off" are present. Update documentation to emphasize the fact that both "mds=off" and "tsx_async_abort=off" have to be specified together for processors that are affected by both TAA and MDS to be effective. [ bp: Massage and add kernel-parameters.txt change too. ] Fixes: 1b42f017415b ("x86/speculation/taa: Add mitigation for TSX Async Abort") Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-doc@vger.kernel.org Cc: Mark Gross <mgross@linux.intel.com> Cc: <stable@vger.kernel.org> Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191115161445.30809-2-longman@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: Add ITLB_MULTIHIT documentationGomez Iglesias, Antonio2019-11-162-0/+164
| | | | | | | | | | | | | | | | commit 7f00cc8d4a51074eb0ad4c3f16c15757b1ddfb7d upstream. 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> [bwh: Backported to 4.9: adjust filenames] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kvm: x86: mmu: Recovery of shattered NX large pagesJunaid Shahid2019-11-161-0/+6
| | | | | | | | | | | | | | | | | | | | | commit 1aa9b9572b10529c2e64e2b8f44025d86e124308 upstream. 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> [bwh: Backported to 4.9: - Update another error path in kvm_create_vm() to use out_err_no_mmu_notifier - Adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kvm: mmu: ITLB_MULTIHIT mitigationPaolo Bonzini2019-11-161-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b8e8c8303ff28c61046a4d0f6ea99aea609a7dc0 upstream. 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> [bwh: Backported to 4.9: - Use kvm_mmu_invalidate_zap_all_pages() instead of kvm_mmu_zap_all_fast() - Don't provide mode for nx_largepages_splitted as all stats are read-only - Adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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