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2021-06-24KVM: stats: Add documentation for binary statistics interfaceJing Zhang
This new API provides a file descriptor for every VM and VCPU to read KVM statistics data in binary format. It is meant to provide a lightweight, flexible, scalable and efficient lock-free solution for user space telemetry applications to pull the statistics data periodically for large scale systems. The pulling frequency could be as high as a few times per second. The statistics descriptors are defined by KVM in kernel and can be by userspace to discover VM/VCPU statistics during the one-time setup stage. The statistics data itself could be read out by userspace telemetry periodically without any extra parsing or setup effort. There are a few existed interface protocols and definitions, but no one can fulfil all the requirements this interface implemented as below: 1. During high frequency periodic stats reading, there should be no extra efforts except the stats data read itself. 2. Support stats annotation, like type (cumulative, instantaneous, peak, histogram, etc) and unit (counter, time, size, cycles, etc). 3. The stats data reading should be free of lock/synchronization. We don't care about the consistency between all the stats data. All stats data can not be read out at exactly the same time. We really care about the change or trend of the stats data. The lock-free solution is not just for efficiency and scalability, also for the stats data accuracy and usability. For example, in the situation that all the stats data readings are protected by a global lock, if one VCPU died somehow with that lock held, then all stats data reading would be blocked, then we have no way from stats data that which VCPU has died. 4. The stats data reading workload can be handed over to other unprivileged process. Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Ricardo Koller <ricarkol@google.com> Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Jing Zhang <jingzhangos@google.com> Message-Id: <20210618222709.1858088-6-jingzhangos@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-23Merge branch 'topic/ppc-kvm' of ↵Paolo Bonzini
https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux into HEAD - Support for the H_RPT_INVALIDATE hypercall - Conversion of Book3S entry/exit to C - Bug fixes
2021-06-22KVM: PPC: Book3S HV: Add KVM_CAP_PPC_RPT_INVALIDATE capabilityBharata B Rao
Now that we have H_RPT_INVALIDATE fully implemented, enable support for the same via KVM_CAP_PPC_RPT_INVALIDATE KVM capability Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210621085003.904767-6-bharata@linux.ibm.com
2021-06-17KVM: X86: Introduce KVM_HC_MAP_GPA_RANGE hypercallAshish Kalra
This hypercall is used by the SEV guest to notify a change in the page encryption status to the hypervisor. The hypercall should be invoked only when the encryption attribute is changed from encrypted -> decrypted and vice versa. By default all guest pages are considered encrypted. The hypercall exits to userspace to manage the guest shared regions and integrate with the userspace VMM's migration code. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Borislav Petkov <bp@suse.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: x86@kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Steve Rutherford <srutherford@google.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Co-developed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <90778988e1ee01926ff9cac447aacb745f954c8c.1623174621.git.ashish.kalra@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-17KVM: x86: Introduce KVM_GET_SREGS2 / KVM_SET_SREGS2Maxim Levitsky
This is a new version of KVM_GET_SREGS / KVM_SET_SREGS. It has the following changes: * Has flags for future extensions * Has vcpu's PDPTRs, allowing to save/restore them on migration. * Lacks obsolete interrupt bitmap (done now via KVM_SET_VCPU_EVENTS) New capability, KVM_CAP_SREGS2 is added to signal the userspace of this ioctl. Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20210607090203.133058-8-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-17KVM: x86: hyper-v: Introduce KVM_CAP_HYPERV_ENFORCE_CPUIDVitaly Kuznetsov
Modeled after KVM_CAP_ENFORCE_PV_FEATURE_CPUID, the new capability allows for limiting Hyper-V features to those exposed to the guest in Hyper-V CPUIDs (0x40000003, 0x40000004, ...). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20210521095204.2161214-3-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-17KVM: mmu: Add slots_arch_lock for memslot arch fieldsBen Gardon
Add a new lock to protect the arch-specific fields of memslots if they need to be modified in a kvm->srcu read critical section. A future commit will use this lock to lazily allocate memslot rmaps for x86. Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20210518173414.450044-5-bgardon@google.com> [Add Documentation/ hunk. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-08KVM: X86: MMU: Use the correct inherited permissions to get shadow pageLai Jiangshan
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>
2021-05-27KVM: rename KVM_REQ_PENDING_TIMER to KVM_REQ_UNBLOCKMarcelo Tosatti
KVM_REQ_UNBLOCK will be used to exit a vcpu from its inner vcpu halt emulation loop. Rename KVM_REQ_PENDING_TIMER to KVM_REQ_UNBLOCK, switch PowerPC to arch specific request bit. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Message-Id: <20210525134321.303768132@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-17Merge tag 'kvmarm-fixes-5.13-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.13, take #1 - Fix regression with irqbypass not restarting the guest on failed connect - Fix regression with debug register decoding resulting in overlapping access - Commit exception state on exit to usrspace - Fix the MMU notifier return values - Add missing 'static' qualifiers in the new host stage-2 code
2021-05-16Merge tag 'usb-5.13-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "Here are some small USB fixes for 5.13-rc2. They consist of a number of resolutions for reported issues: - typec fixes for found problems - xhci fixes and quirk additions - dwc3 driver fixes - minor fixes found by Coverity - cdc-wdm fixes for reported problems All of these have been in linux-next for a few days with no reported issues" * tag 'usb-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (28 commits) usb: core: hub: fix race condition about TRSMRCY of resume usb: typec: tcpm: Fix SINK_DISCOVERY current limit for Rp-default xhci: Add reset resume quirk for AMD xhci controller. usb: xhci: Increase timeout for HC halt xhci: Do not use GFP_KERNEL in (potentially) atomic context xhci: Fix giving back cancelled URBs even if halted endpoint can't reset xhci-pci: Allow host runtime PM as default for Intel Alder Lake xHCI usb: musb: Fix an error message usb: typec: tcpm: Fix wrong handling for Not_Supported in VDM AMS usb: typec: tcpm: Send DISCOVER_IDENTITY from dedicated work usb: typec: ucsi: Retrieve all the PDOs instead of just the first 4 usb: fotg210-hcd: Fix an error message docs: usb: function: Modify path name usb: dwc3: omap: improve extcon initialization usb: typec: ucsi: Put fwnode in any case during ->probe() usb: typec: tcpm: Fix wrong handling in GET_SINK_CAP usb: dwc2: Remove obsolete MODULE_ constants from platform.c usb: dwc3: imx8mp: fix error return code in dwc3_imx8mp_probe() usb: dwc3: imx8mp: detect dwc3 core node via compatible string usb: dwc3: gadget: Return success always for kick transfer in ep queue ...
2021-05-16Merge tag 'x86_urgent_for_v5.13_rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: "The three SEV commits are not really urgent material. But we figured since getting them in now will avoid a huge amount of conflicts between future SEV changes touching tip, the kvm and probably other trees, sending them to you now would be best. The idea is that the tip, kvm etc branches for 5.14 will all base ontop of -rc2 and thus everything will be peachy. What is more, those changes are purely mechanical and defines movement so they should be fine to go now (famous last words). Summary: - Enable -Wundef for the compressed kernel build stage - Reorganize SEV code to streamline and simplify future development" * tag 'x86_urgent_for_v5.13_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot/compressed: Enable -Wundef x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG x86/sev: Move GHCB MSR protocol and NAE definitions in a common header x86/sev-es: Rename sev-es.{ch} to sev.{ch}
2021-05-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "13 patches. Subsystems affected by this patch series: resource, squashfs, hfsplus, modprobe, and mm (hugetlb, slub, userfaultfd, ksm, pagealloc, kasan, pagemap, and ioremap)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm/ioremap: fix iomap_max_page_shift docs: admin-guide: update description for kernel.modprobe sysctl hfsplus: prevent corruption in shrinking truncate mm/filemap: fix readahead return types kasan: fix unit tests with CONFIG_UBSAN_LOCAL_BOUNDS enabled mm: fix struct page layout on 32-bit systems ksm: revert "use GET_KSM_PAGE_NOLOCK to get ksm page in remove_rmap_item_from_tree()" userfaultfd: release page in error path to avoid BUG_ON squashfs: fix divide error in calculate_skip() kernel/resource: fix return code check in __request_free_mem_region mm, slub: move slub_debug static key enabling outside slab_mutex mm/hugetlb: fix cow where page writtable in child mm/hugetlb: fix F_SEAL_FUTURE_WRITE
2021-05-15Merge tag 'erofs-for-5.13-rc2-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs fixes from Gao Xiang: "This mainly fixes 1 lcluster-sized pclusters for the big pcluster feature, which can be forcely generated by mkfs as a specific on-disk case for per-(sub)file compression strategies but missed to handle in runtime properly. Also, documentation updates are included to fix the broken illustration due to the ReST conversion by accident and complete the big pcluster introduction. Summary: - update documentation to fix the broken illustration due to ReST conversion by accident at that time and complete the big pcluster introduction - fix 1 lcluster-sized pclusters for the big pcluster feature" * tag 'erofs-for-5.13-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: fix 1 lcluster-sized pcluster for big pcluster erofs: update documentation about data compression erofs: fix broken illustration in documentation
2021-05-15Merge tag 'libnvdimm-fixes-5.13-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm fixes from Dan Williams: "A regression fix for a bootup crash condition introduced in this merge window and some other minor fixups: - Fix regression in ACPI NFIT table handling leading to crashes and driver load failures. - Move the nvdimm mailing list - Miscellaneous minor fixups" * tag 'libnvdimm-fixes-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: ACPI: NFIT: Fix support for variable 'SPA' structure size MAINTAINERS: Move nvdimm mailing list tools/testing/nvdimm: Make symbol '__nfit_test_ioremap' static libnvdimm: Remove duplicate struct declaration
2021-05-14docs: admin-guide: update description for kernel.modprobe sysctlRasmus Villemoes
When I added CONFIG_MODPROBE_PATH, I neglected to update Documentation/. It's still true that this defaults to /sbin/modprobe, but now via a level of indirection. So document that the kernel might have been built with something other than /sbin/modprobe as the initial value. Link: https://lkml.kernel.org/r/20210420125324.1246826-1-linux@rasmusvillemoes.dk Fixes: 17652f4240f7a ("modules: add CONFIG_MODPROBE_PATH") Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-12Merge tag 'docs-5.13-3' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A set of straightforward documentation fixes" * tag 'docs-5.13-3' of git://git.lwn.net/linux: Remove link to nonexistent rocket driver docs docs: networking: device_drivers: fix bad usage of UTF-8 chars docs: hwmon: tmp103.rst: fix bad usage of UTF-8 chars docs: ABI: remove some spurious characters docs: ABI: remove a meaningless UTF-8 character docs: cdrom-standard.rst: get rid of uneeded UTF-8 chars Documentation: drop optional BOMs docs/zh_CN: Remove obsolete translation file
2021-05-12MAINTAINERS: Move nvdimm mailing listDan Williams
After seeing some users have subscription management trouble, more spam than other Linux development lists, and considering some of the benefits of kernel.org hosted lists, nvdimm and persistent memory development is moving to nvdimm@lists.linux.dev. The old list will remain up until v5.14-rc1 and shutdown thereafter. Cc: Ira Weiny <ira.weiny@intel.com> Cc: Oliver O'Halloran <oohall@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Jan Kara <jack@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/161898872871.3406469.4054282559340528393.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-05-11Remove link to nonexistent rocket driver docsDesmond Cheong Zhi Xi
The rocket driver and documentation were removed in this commit, but the corresponding entry in index.rst was not removed. Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com> Fixes: 3b00b6af7a5b ("tty: rocket, remove the driver") Link: https://lore.kernel.org/r/20210511134937.2442291-1-desmondcheongzx@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-11docs: networking: device_drivers: fix bad usage of UTF-8 charsMauro Carvalho Chehab
Probably because the original file was pre-processed by some tool, both i40e.rst and iavf.rst files are using this character: - U+2013 ('–'): EN DASH meaning an hyphen when calling a command line application, which is obviously wrong. So, replace them by an hyphen, ensuring that it will be properly displayed as literals when building the documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/95eb2a48d0ca3528780ce0dfce64359977fa8cb3.1620744606.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-11docs: hwmon: tmp103.rst: fix bad usage of UTF-8 charsMauro Carvalho Chehab
While UTF-8 characters can be used at the Linux documentation, the best is to use them only when ASCII doesn't offer a good replacement. So, replace the occurences of the following UTF-8 characters: - U+2013 ('–'): EN DASH In this specific case, EN DASH was used instead of a minus sign. So, replace it by a single hyphen. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/73b3c7c1eef5c12ddc941624d23689313bd56529.1620744606.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-11docs: ABI: remove some spurious charactersMauro Carvalho Chehab
The KernelVersion tag contains some spurious UTF-8 characters for no reason. Drop them. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/6d774ad6cb3795a177309503a39f8f1b5e309d64.1620744606.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-11docs: ABI: remove a meaningless UTF-8 characterMauro Carvalho Chehab
Those two files have this character: - U+00ac ('¬'): NOT SIGN at the end of the first line, apparently for no reason. Drop them. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/6cd3f0b47568fecb7889fd18d1d744c3aaf73866.1620744606.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-11docs: cdrom-standard.rst: get rid of uneeded UTF-8 charsMauro Carvalho Chehab
This file was converted from a LaTeX one. The conversion used some UTF-8 characters at the literal blocks. Replace them by normal ASCII characters. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Acked-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/79c3f482da17ea48d69b6e6ad1b7fb102b9dd7bf.1620744606.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-11erofs: update documentation about data compressionGao Xiang
Add more description about (NON)HEAD lclusters, and the new big pcluster feature. Link: https://lore.kernel.org/r/20210511084414.21305-1-xiang@kernel.org Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <xiang@kernel.org>
2021-05-11erofs: fix broken illustration in documentationGao Xiang
Illustration was broken after ReST conversion by accident. (checked by 'make SPHINXDIRS="filesystems" htmldocs') Link: https://lore.kernel.org/r/20210510162506.28637-1-xiang@kernel.org Fixes: e66d8631ddb3 ("docs: filesystems: convert erofs.txt to ReST") Reviewed-by: Chao Yu <yuchao0@huawei.com> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Gao Xiang <xiang@kernel.org>
2021-05-10Documentation: drop optional BOMsRandy Dunlap
A few of the Documentation .rst files begin with a Unicode byte order mark (BOM). The BOM may signify endianess for 16-bit or 32-bit encodings or indicate that the text stream is indeed Unicode. We don't need it for either of those uses. It may also interfere with (confuse) some software. Since we don't need it and its use is optional, just delete the uses of it in Documentation/. https://en.wikipedia.org/wiki/Byte_order_mark Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Link: https://lore.kernel.org/r/20210506231907.14359-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-10docs/zh_CN: Remove obsolete translation fileWan Jiabing
This translation file was replaced by Documentation/translations/zh_CN/admin-guide/security-bugs.rst which was created in commit 2d153571003b ("docs/zh_CN: Add zh_CN/admin-guide/security-bugs.rst"). This is a translation left over from history. Remove it. Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Acked-by: Wu XiangCheng <bobwxc@email.cn> Link: https://lore.kernel.org/r/20210508030741.82655-1-wanjiabing@vivo.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-10Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: - Lots of bug fixes. - Fix virtualization of RDPID - Virtualization of DR6_BUS_LOCK, which on bare metal is new to this release - More nested virtualization migration fixes (nSVM and eVMCS) - Fix for KVM guest hibernation - Fix for warning in SEV-ES SRCU usage - Block KVM from loading on AMD machines with 5-level page tables, due to the APM not mentioning how host CR4.LA57 exactly impacts the guest. * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (48 commits) KVM: SVM: Move GHCB unmapping to fix RCU warning KVM: SVM: Invert user pointer casting in SEV {en,de}crypt helpers kvm: Cap halt polling at kvm->max_halt_poll_ns tools/kvm_stat: Fix documentation typo KVM: x86: Prevent deadlock against tk_core.seq KVM: x86: Cancel pvclock_gtod_work on module removal KVM: x86: Prevent KVM SVM from loading on kernels with 5-level paging KVM: X86: Expose bus lock debug exception to guest KVM: X86: Add support for the emulation of DR6_BUS_LOCK bit KVM: PPC: Book3S HV: Fix conversion to gfn-based MMU notifier callbacks KVM: x86: Hide RDTSCP and RDPID if MSR_TSC_AUX probing failed KVM: x86: Tie Intel and AMD behavior for MSR_TSC_AUX to guest CPU model KVM: x86: Move uret MSR slot management to common x86 KVM: x86: Export the number of uret MSRs to vendor modules KVM: VMX: Disable loading of TSX_CTRL MSR the more conventional way KVM: VMX: Use common x86's uret MSR list as the one true list KVM: VMX: Use flag to indicate "active" uret MSRs instead of sorting list KVM: VMX: Configure list of user return MSRs at module init KVM: x86: Add support for RDPID without RDTSCP KVM: SVM: Probe and load MSR_TSC_AUX regardless of RDTSCP support in host ...
2021-05-10docs: usb: function: Modify path nameWei Ming Chen
Original path does not exists, so changed to "Documentation/ABI/testing/configfs-usb-gadget" Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com> Link: https://lore.kernel.org/r/20210506122020.7117-1-jj251510319013@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-10usb: Restore the reference to ch9.hFabio Estevam
Keep the textual reference to ch9.h as it was prior to commit caa93d9bd2d7 ("usb: Fix up movement of USB core kerneldoc location"). As linux/usb/ch9.h does not contain comments anymore, explain that drivers/usb/common/common.c includes such header and provides declarations of a few utilities routines for manipulating the data types from ch9.h. Also mention that drivers/usb/common/debug.c contains some functions for creating debug output. Fixes: caa93d9bd2d7 ("usb: Fix up movement of USB core kerneldoc location") Reported-by: Alan Stern <stern@rowland.harvard.edu> Suggested-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Fabio Estevam <festevam@gmail.com> Link: https://lore.kernel.org/r/20210425153253.2542816-1-festevam@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-10x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFGBrijesh Singh
The SYSCFG MSR continued being updated beyond the K8 family; drop the K8 name from it. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Joerg Roedel <jroedel@suse.de> Link: https://lkml.kernel.org/r/20210427111636.1207-4-brijesh.singh@amd.com
2021-05-09Merge tag 'sched-urgent-2021-05-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "A set of scheduler updates: - Prevent PSI state corruption when schedule() races with cgroup move. A recent commit combined two PSI callbacks to reduce the number of cgroup tree updates, but missed that schedule() can drop rq::lock for load balancing, which opens the race window for cgroup_move_task() which then observes half updated state. The fix is to solely use task::ps_flags instead of looking at the potentially mismatching scheduler state - Prevent an out-of-bounds access in uclamp caused bu a rounding division which can lead to an off-by-one error exceeding the buckets array size. - Prevent unfairness caused by missing load decay when a task is attached to a cfs runqueue. The old load of the task was attached to the runqueue and never removed. Fix it by enforcing the load update through the hierarchy for unthrottled run queue instances. - A documentation fix fot the 'sched_verbose' command line option" * tag 'sched-urgent-2021-05-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: Fix unfairness caused by missing load decay sched: Fix out-of-bound access in uclamp psi: Fix psi state corruption when schedule() races with cgroup move sched,doc: sched_debug_verbose cmdline should be sched_verbose
2021-05-08Merge tag 'kbuild-v5.13-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - Convert sh and sparc to use generic shell scripts to generate the syscall headers - refactor .gitignore files - Update kernel/config_data.gz only when the content of the .config is really changed, which avoids the unneeded re-link of vmlinux - move "remove stale files" workarounds to scripts/remove-stale-files - suppress unused-but-set-variable warnings by default for Clang as well - fix locale setting LANG=C to LC_ALL=C - improve 'make distclean' - always keep intermediate objects from scripts/link-vmlinux.sh - move IF_ENABLED out of <linux/kconfig.h> to make it self-contained - misc cleanups * tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h> kbuild: Don't remove link-vmlinux temporary files on exit/signal kbuild: remove the unneeded comments for external module builds kbuild: make distclean remove tag files in sub-directories kbuild: make distclean work against $(objtree) instead of $(srctree) kbuild: refactor modname-multi by using suffix-search kbuild: refactor fdtoverlay rule kbuild: parameterize the .o part of suffix-search arch: use cross_compiling to check whether it is a cross build or not kbuild: remove ARCH=sh64 support from top Makefile .gitignore: prefix local generated files with a slash kbuild: replace LANG=C with LC_ALL=C Makefile: Move -Wno-unused-but-set-variable out of GCC only block kbuild: add a script to remove stale generated files kbuild: update config_data.gz only when the content of .config is changed .gitignore: ignore only top-level modules.builtin .gitignore: move tags and TAGS close to other tag files kernel/.gitgnore: remove stale timeconst.h and hz.bc usr/include: refactor .gitignore genksyms: fix stale comment ...
2021-05-08Merge tag 'powerpc-5.13-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates and fixes from Michael Ellerman: "A bit of a mixture of things, tying up some loose ends. There's the removal of the nvlink code, which dependend on a commit in the vfio tree. Then the enablement of huge vmalloc which was in next for a few weeks but got dropped due to conflicts. And there's also a few fixes. Summary: - Remove the nvlink support now that it's only user has been removed. - Enable huge vmalloc mappings for Radix MMU (P9). - Fix KVM conversion to gfn-based MMU notifier callbacks. - Fix a kexec/kdump crash with hot plugged CPUs. - Fix boot failure on 32-bit with CONFIG_STACKPROTECTOR. - Restore alphabetic order of the selects under CONFIG_PPC. Thanks to: Christophe Leroy, Christoph Hellwig, Nicholas Piggin, Sandipan Das, and Sourabh Jain" * tag 'powerpc-5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: KVM: PPC: Book3S HV: Fix conversion to gfn-based MMU notifier callbacks powerpc/kconfig: Restore alphabetic order of the selects under CONFIG_PPC powerpc/32: Fix boot failure with CONFIG_STACKPROTECTOR powerpc/powernv/memtrace: Fix dcache flushing powerpc/kexec_file: Use current CPU info while setting up FDT powerpc/64s/radix: Enable huge vmalloc mappings powerpc/powernv: remove the nvlink support
2021-05-08Merge tag 'net-5.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Networking fixes for 5.13-rc1, including fixes from bpf, can and netfilter trees. Self-contained fixes, nothing risky. Current release - new code bugs: - dsa: ksz: fix a few bugs found by static-checker in the new driver - stmmac: fix frame preemption handshake not triggering after interface restart Previous releases - regressions: - make nla_strcmp handle more then one trailing null character - fix stack OOB reads while fragmenting IPv4 packets in openvswitch and net/sched - sctp: do asoc update earlier in sctp_sf_do_dupcook_a - sctp: delay auto_asconf init until binding the first addr - stmmac: clear receive all(RA) bit when promiscuous mode is off - can: mcp251x: fix resume from sleep before interface was brought up Previous releases - always broken: - bpf: fix leakage of uninitialized bpf stack under speculation - bpf: fix masking negation logic upon negative dst register - netfilter: don't assume that skb_header_pointer() will never fail - only allow init netns to set default tcp cong to a restricted algo - xsk: fix xp_aligned_validate_desc() when len == chunk_size to avoid false positive errors - ethtool: fix missing NLM_F_MULTI flag when dumping - can: m_can: m_can_tx_work_queue(): fix tx_skb race condition - sctp: fix a SCTP_MIB_CURRESTAB leak in sctp_sf_do_dupcook_b - bridge: fix NULL-deref caused by a races between assigning rx_handler_data and setting the IFF_BRIDGE_PORT bit Latecomer: - seg6: add counters support for SRv6 Behaviors" * tag 'net-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (73 commits) atm: firestream: Use fallthrough pseudo-keyword net: stmmac: Do not enable RX FIFO overflow interrupts mptcp: fix splat when closing unaccepted socket i40e: Remove LLDP frame filters i40e: Fix PHY type identifiers for 2.5G and 5G adapters i40e: fix the restart auto-negotiation after FEC modified i40e: Fix use-after-free in i40e_client_subtask() i40e: fix broken XDP support netfilter: nftables: avoid potential overflows on 32bit arches netfilter: nftables: avoid overflows in nft_hash_buckets() tcp: Specify cmsgbuf is user pointer for receive zerocopy. mlxsw: spectrum_mr: Update egress RIF list before route's action net: ipa: fix inter-EE IRQ register definitions can: m_can: m_can_tx_work_queue(): fix tx_skb race condition can: mcp251x: fix resume from sleep before interface was brought up can: mcp251xfd: mcp251xfd_probe(): add missing can_rx_offload_del() in error path can: mcp251xfd: mcp251xfd_probe(): fix an error pointer dereference in probe netfilter: nftables: Fix a memleak from userdata error path in new objects netfilter: remove BUG_ON() after skb_header_pointer() netfilter: nfnetlink_osf: Fix a missing skb_header_pointer() NULL check ...
2021-05-08Merge branch 'master' into nextMichael Ellerman
Merge master back into next, this allows us to resolve some conflicts in arch/powerpc/Kconfig, and also re-sort the symbols under config PPC so that they are in alphabetical order again.
2021-05-07Merge tag 'i3c/for-5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull i3cupdates from Alexandre Belloni: "Fix i3c_master_register error path" * tag 'i3c/for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: Revert "i3c master: fix missing destroy_workqueue() on error in i3c_master_register" dt-bindings: i3c: Fix silvaco,i3c-master-v1 compatible string i3c: master: svc: remove redundant assignment to cmd->read_len
2021-05-07Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull more arm64 updates from Catalin Marinas: "A mix of fixes and clean-ups that turned up too late for the first pull request: - Restore terminal stack frame records. Their previous removal caused traces which cross secondary_start_kernel to terminate one entry too late, with a spurious "0" entry. - Fix boot warning with pseudo-NMI due to the way we manipulate the PMR register. - ACPI fixes: avoid corruption of interrupt mappings on watchdog probe failure (GTDT), prevent unregistering of GIC SGIs. - Force SPARSEMEM_VMEMMAP as the only memory model, it saves with having to test all the other combinations. - Documentation fixes and updates: tagged address ABI exceptions on brk/mmap/mremap(), event stream frequency, update booting requirements on the configuration of traps" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: kernel: Update the stale comment arm64: Fix the documented event stream frequency arm64: entry: always set GIC_PRIO_PSR_I_SET during entry arm64: Explicitly document boot requirements for SVE arm64: Explicitly require that FPSIMD instructions do not trap arm64: Relax booting requirements for configuration of traps arm64: cpufeatures: use min and max arm64: stacktrace: restore terminal records arm64/vdso: Discard .note.gnu.property sections in vDSO arm64: doc: Add brk/mmap/mremap() to the Tagged Address ABI Exceptions psci: Remove unneeded semicolon ACPI: irq: Prevent unregistering of GIC SGIs ACPI: GTDT: Don't corrupt interrupt mappings on watchdow probe failure arm64: Show three registers per line arm64: remove HAVE_DEBUG_BUGVERBOSE arm64: alternative: simplify passing alt_region arm64: Force SPARSEMEM_VMEMMAP as the only memory management model arm64: vdso32: drop -no-integrated-as flag
2021-05-07doc/kvm: Fix wrong entry for KVM_CAP_X86_MSR_FILTERSiddharth Chandrasekaran
The capability that exposes new ioctl KVM_X86_SET_MSR_FILTER to userspace is specified incorrectly as the ioctl itself (instead of KVM_CAP_X86_MSR_FILTER). This patch fixes it. Fixes: 1a155254ff93 ("KVM: x86: Introduce MSR filtering") Reviewed-by: Alexander Graf <graf@amazon.de> Signed-off-by: Siddharth Chandrasekaran <sidcha@amazon.de> Message-Id: <20210503120059.9283-1-sidcha@amazon.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-07Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge yet more updates from Andrew Morton: "This is everything else from -mm for this merge window. 90 patches. Subsystems affected by this patch series: mm (cleanups and slub), alpha, procfs, sysctl, misc, core-kernel, bitmap, lib, compat, checkpatch, epoll, isofs, nilfs2, hpfs, exit, fork, kexec, gcov, panic, delayacct, gdb, resource, selftests, async, initramfs, ipc, drivers/char, and spelling" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (90 commits) mm: fix typos in comments mm: fix typos in comments treewide: remove editor modelines and cruft ipc/sem.c: spelling fix fs: fat: fix spelling typo of values kernel/sys.c: fix typo kernel/up.c: fix typo kernel/user_namespace.c: fix typos kernel/umh.c: fix some spelling mistakes include/linux/pgtable.h: few spelling fixes mm/slab.c: fix spelling mistake "disired" -> "desired" scripts/spelling.txt: add "overflw" scripts/spelling.txt: Add "diabled" typo scripts/spelling.txt: add "overlfow" arm: print alloc free paths for address in registers mm/vmalloc: remove vwrite() mm: remove xlate_dev_kmem_ptr() drivers/char: remove /dev/kmem for good mm: fix some typos and code style problems ipc/sem.c: mundane typo fixes ...
2021-05-07drivers/char: remove /dev/kmem for goodDavid Hildenbrand
Patch series "drivers/char: remove /dev/kmem for good". Exploring /dev/kmem and /dev/mem in the context of memory hot(un)plug and memory ballooning, I started questioning the existence of /dev/kmem. Comparing it with the /proc/kcore implementation, it does not seem to be able to deal with things like a) Pages unmapped from the direct mapping (e.g., to be used by secretmem) -> kern_addr_valid(). virt_addr_valid() is not sufficient. b) Special cases like gart aperture memory that is not to be touched -> mem_pfn_is_ram() Unless I am missing something, it's at least broken in some cases and might fault/crash the machine. Looks like its existence has been questioned before in 2005 and 2010 [1], after ~11 additional years, it might make sense to revive the discussion. CONFIG_DEVKMEM is only enabled in a single defconfig (on purpose or by mistake?). All distributions disable it: in Ubuntu it has been disabled for more than 10 years, in Debian since 2.6.31, in Fedora at least starting with FC3, in RHEL starting with RHEL4, in SUSE starting from 15sp2, and OpenSUSE has it disabled as well. 1) /dev/kmem was popular for rootkits [2] before it got disabled basically everywhere. Ubuntu documents [3] "There is no modern user of /dev/kmem any more beyond attackers using it to load kernel rootkits.". RHEL documents in a BZ [5] "it served no practical purpose other than to serve as a potential security problem or to enable binary module drivers to access structures/functions they shouldn't be touching" 2) /proc/kcore is a decent interface to have a controlled way to read kernel memory for debugging puposes. (will need some extensions to deal with memory offlining/unplug, memory ballooning, and poisoned pages, though) 3) It might be useful for corner case debugging [1]. KDB/KGDB might be a better fit, especially, to write random memory; harder to shoot yourself into the foot. 4) "Kernel Memory Editor" [4] hasn't seen any updates since 2000 and seems to be incompatible with 64bit [1]. For educational purposes, /proc/kcore might be used to monitor value updates -- or older kernels can be used. 5) It's broken on arm64, and therefore, completely disabled there. Looks like it's essentially unused and has been replaced by better suited interfaces for individual tasks (/proc/kcore, KDB/KGDB). Let's just remove it. [1] https://lwn.net/Articles/147901/ [2] https://www.linuxjournal.com/article/10505 [3] https://wiki.ubuntu.com/Security/Features#A.2Fdev.2Fkmem_disabled [4] https://sourceforge.net/projects/kme/ [5] https://bugzilla.redhat.com/show_bug.cgi?id=154796 Link: https://lkml.kernel.org/r/20210324102351.6932-1-david@redhat.com Link: https://lkml.kernel.org/r/20210324102351.6932-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Alexander A. Klimov" <grandmaster@al2klimov.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Brian Cain <bcain@codeaurora.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Chris Zankel <chris@zankel.net> Cc: Corentin Labbe <clabbe@baylibre.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Gregory Clement <gregory.clement@bootlin.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Hillf Danton <hdanton@sina.com> Cc: huang ying <huang.ying.caritas@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: James Troup <james.troup@canonical.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kairui Song <kasong@redhat.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@kernel.org> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Niklas Schnelle <schnelle@linux.ibm.com> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com> Cc: openrisc@lists.librecores.org Cc: Palmer Dabbelt <palmerdabbelt@google.com> Cc: Paul Mackerras <paulus@samba.org> Cc: "Pavel Machek (CIP)" <pavel@denx.de> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Pierre Morel <pmorel@linux.ibm.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Rich Felker <dalias@libc.org> Cc: Robert Richter <rric@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Cc: sparclinux@vger.kernel.org Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Theodore Dubois <tblodt@icloud.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: William Cohen <wcohen@redhat.com> Cc: Xiaoming Ni <nixiaoming@huawei.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07init/initramfs.c: do unpacking asynchronouslyRasmus Villemoes
Patch series "background initramfs unpacking, and CONFIG_MODPROBE_PATH", v3. These two patches are independent, but better-together. The second is a rather trivial patch that simply allows the developer to change "/sbin/modprobe" to something else - e.g. the empty string, so that all request_module() during early boot return -ENOENT early, without even spawning a usermode helper, needlessly synchronizing with the initramfs unpacking. The first patch delegates decompressing the initramfs to a worker thread, allowing do_initcalls() in main.c to proceed to the device_ and late_ initcalls without waiting for that decompression (and populating of rootfs) to finish. Obviously, some of those later calls may rely on the initramfs being available, so I've added synchronization points in the firmware loader and usermodehelper paths - there might be other places that would need this, but so far no one has been able to think of any places I have missed. There's not much to win if most of the functionality needed during boot is only available as modules. But systems with a custom-made .config and initramfs can boot faster, partly due to utilizing more than one cpu earlier, partly by avoiding known-futile modprobe calls (which would still trigger synchronization with the initramfs unpacking, thus eliminating most of the first benefit). This patch (of 2): Most of the boot process doesn't actually need anything from the initramfs, until of course PID1 is to be executed. So instead of doing the decompressing and populating of the initramfs synchronously in populate_rootfs() itself, push that off to a worker thread. This is primarily motivated by an embedded ppc target, where unpacking even the rather modest sized initramfs takes 0.6 seconds, which is long enough that the external watchdog becomes unhappy that it doesn't get attention soon enough. By doing the initramfs decompression in a worker thread, we get to do the device_initcalls and hence start petting the watchdog much sooner. Normal desktops might benefit as well. On my mostly stock Ubuntu kernel, my initramfs is a 26M xz-compressed blob, decompressing to around 126M. That takes almost two seconds: [ 0.201454] Trying to unpack rootfs image as initramfs... [ 1.976633] Freeing initrd memory: 29416K Before this patch, these lines occur consecutively in dmesg. With this patch, the timestamps on these two lines is roughly the same as above, but with 172 lines inbetween - so more than one cpu has been kept busy doing work that would otherwise only happen after the populate_rootfs() finished. Should one of the initcalls done after rootfs_initcall time (i.e., device_ and late_ initcalls) need something from the initramfs (say, a kernel module or a firmware blob), it will simply wait for the initramfs unpacking to be done before proceeding, which should in theory make this completely safe. But if some driver pokes around in the filesystem directly and not via one of the official kernel interfaces (i.e. request_firmware*(), call_usermodehelper*) that theory may not hold - also, I certainly might have missed a spot when sprinkling wait_for_initramfs(). So there is an escape hatch in the form of an initramfs_async= command line parameter. Link: https://lkml.kernel.org/r/20210313212528.2956377-1-linux@rasmusvillemoes.dk Link: https://lkml.kernel.org/r/20210313212528.2956377-2-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07scripts/gdb: add lx_current support for arm64Barry Song
arm64 uses SP_EL0 to save the current task_struct address. While running in EL0, SP_EL0 is clobbered by userspace. So if the upper bit is not 1 (not TTBR1), the current address is invalid. This patch checks the upper bit of SP_EL0, if the upper bit is 1, lx_current() of arm64 will return the derefrence of current task. Otherwise, lx_current() will tell users they are running in userspace(EL0). While arm64 is running in EL0, it is actually pointless to print current task as the memory of kernel space is not accessible in EL0. Link: https://lkml.kernel.org/r/20210314203444.15188-3-song.bao.hua@hisilicon.com Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kieran Bingham <kbingham@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07scripts/gdb: document lx_current is only supported by x86Barry Song
Patch series "scripts/gdb: clarify the platforms supporting lx_current and add arm64 support", v2. lx_current depends on per_cpu current_task variable which exists on x86 only. so it actually works on x86 only. the 1st patch documents this clearly; the 2nd patch adds support for arm64. This patch (of 2): x86 is the only architecture which has per_cpu current_task: arch$ git grep current_task | grep -i per_cpu x86/include/asm/current.h:DECLARE_PER_CPU(struct task_struct *, current_task); x86/kernel/cpu/common.c:DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned = x86/kernel/cpu/common.c:EXPORT_PER_CPU_SYMBOL(current_task); x86/kernel/cpu/common.c:DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task; x86/kernel/cpu/common.c:EXPORT_PER_CPU_SYMBOL(current_task); x86/kernel/smpboot.c: per_cpu(current_task, cpu) = idle; On other architectures, lx_current() will lead to a python exception: (gdb) p $lx_current().pid Python Exception <class 'gdb.error'> No symbol "current_task" in current context.: Error occurred in Python: No symbol "current_task" in current context. To avoid more people struggling and wasting time in other architectures, document it. Link: https://lkml.kernel.org/r/20210314203444.15188-1-song.bao.hua@hisilicon.com Link: https://lkml.kernel.org/r/20210314203444.15188-2-song.bao.hua@hisilicon.com Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: - three new touchscreen drivers: Hycon HY46XX, ILITEK Lego Series, and MStar MSG2638 - a new driver for Azoteq IQS626A proximity and touch controller - addition of Amazon Game Controller to the list of devices handled by the xpad driver - Elan touchscreen driver will avoid binding to devices described as I2CHID compatible in ACPI tables - various driver fixes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (56 commits) Input: xpad - add support for Amazon Game Controller Input: ili210x - add missing negation for touch indication on ili210x MAINTAINERS: repair reference in HYCON HY46XX TOUCHSCREEN SUPPORT Input: add driver for the Hycon HY46XX touchpanel series dt-bindings: touchscreen: Add HY46XX bindings dt-bindings: Add Hycon Technology vendor prefix Input: cyttsp - flag the device properly Input: cyttsp - set abs params for ABS_MT_TOUCH_MAJOR Input: cyttsp - drop the phys path Input: cyttsp - reduce reset pulse timings Input: cyttsp - error message on boot mode exit error Input: apbps2 - remove useless variable Input: mms114 - support MMS136 Input: mms114 - convert bindings to YAML and extend Input: Add support for ILITEK Lego Series dt-bindings: input: touchscreen: ilitek_ts_i2c: Add bindings Input: add MStar MSG2638 touchscreen driver dt-bindings: input/touchscreen: add bindings for msg2638 Input: silead - add workaround for x86 BIOS-es which bring the chip up in a stuck state Input: elants_i2c - do not bind to i2c-hid compatible ACPI instantiated devices ...
2021-05-06Merge tag 'vfio-v5.13-rc1pt2' of git://github.com/awilliam/linux-vfioLinus Torvalds
Pull more VFIO updates from Alex Williamson: "A second small set of commits for this merge window, primarily to unbreak some deletions from our uAPI header. - Additional mdev sample driver cleanup (Dan Carpenter) - Doc fix (Alyssa Ross) - Unbreak uAPI from NVLink2 support removal (Alex Williamson)" * tag 'vfio-v5.13-rc1pt2' of git://github.com/awilliam/linux-vfio: docs: vfio: fix typo vfio/pci: Revert nvlink removal uAPI breakage vfio/mdev: remove unnecessary NULL check in mbochs_create()
2021-05-06Merge tag 'acpi-5.13-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI fixes from Rafael Wysocki: "These revert one recent commit that turned out to be problematic, address two issues in the ACPI "custom method" interface and update GPIO properties documentation. Specifics: - Revent recent commit related to the handling of ACPI power resources during initialization, because it turned out to cause problems to occur on some systems (Rafael Wysocki). - Fix potential use-after-free and potential memory leak in the ACPI "custom method" debugfs interface (Mark Langsdorf). - Update ACPI GPIO properties documentation to cover assumptions regarding GPIO polarity (Andy Shevchenko)" * tag 'acpi-5.13-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: Revert "ACPI: scan: Turn off unused power resources during initialization" ACPI: custom_method: fix a possible memory leak ACPI: custom_method: fix potential use-after-free issue Documentation: firmware-guide: gpio-properties: Add note to SPI CS case
2021-05-06Merge tag 'devicetree-fixes-for-5.13-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull devicetree fixes from Rob Herring: - Several Renesas binding fixes to fix warnings - Remove duplicate compatibles in 8250 binding - Remove orphaned Sigma Designs Tango bindings - Fix bcm2711-hdmi binding to use 'additionalProperties' - Fix idt,32434-pic warning for missing 'interrupts' property - Fix 'stored but not read' warnings in DT overlay code * tag 'devicetree-fixes-for-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: dt-bindings: net: renesas,etheravb: Fix optional second clock name dt-bindings: display: renesas,du: Add missing power-domains property dt-bindings: media: renesas,vin: Make resets optional on R-Car Gen1 dt-bindings: PCI: rcar-pci-host: Document missing R-Car H1 support of: overlay: Remove redundant assignment to ret dt-bindings: serial: 8250: Remove duplicated compatible strings dt-bindings: Remove unused Sigma Designs Tango bindings dt-bindings: bcm2711-hdmi: Fix broken schema dt-bindings: interrupt-controller: idt,32434-pic: Add missing interrupts property
2021-05-06Merge tag 'riscv-for-linus-5.13-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the memtest= kernel command-line argument. - Support for building the kernel with FORTIFY_SOURCE. - Support for generic clockevent broadcasts. - Support for the buildtar build target. - Some build system cleanups to pass more LLVM-friendly arguments. - Support for kprobes. - A rearranged kernel memory map, the first part of supporting sv48 systems. - Improvements to kexec, along with support for kdump and crash kernels. - An alternatives-based errata framework, along with support for handling a pair of errata that manifest on some SiFive designs (including the HiFive Unmatched). - Support for XIP. - A device tree for the Microchip PolarFire ICICLE SoC and associated dev board. ... along with a bunch of cleanups. There are already a handful of fixes on the list so there will likely be a part 2. * tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (45 commits) RISC-V: Always define XIP_FIXUP riscv: Remove 32b kernel mapping from page table dump riscv: Fix 32b kernel build with CONFIG_DEBUG_VIRTUAL=y RISC-V: Fix error code returned by riscv_hartid_to_cpuid() RISC-V: Enable Microchip PolarFire ICICLE SoC RISC-V: Initial DTS for Microchip ICICLE board dt-bindings: riscv: microchip: Add YAML documentation for the PolarFire SoC RISC-V: Add Microchip PolarFire SoC kconfig option RISC-V: enable XIP RISC-V: Add crash kernel support RISC-V: Add kdump support RISC-V: Improve init_resources() RISC-V: Add kexec support RISC-V: Add EM_RISCV to kexec UAPI header riscv: vdso: fix and clean-up Makefile riscv/mm: Use BUG_ON instead of if condition followed by BUG. riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe riscv: Set ARCH_HAS_STRICT_MODULE_RWX if MMU riscv: module: Create module allocations without exec permissions riscv: bpf: Avoid breaking W^X ...