June 2024 - Linux-kselftest-mirror

[PATCH RFC 0/5] mm/gup: Introduce exclusive GUP pinning

by Elliot Berman

In arm64 pKVM and QuIC's Gunyah protected VM model, we want to support grabbing shmem user pages instead of using KVM's guestmemfd. These hypervisors provide a different isolation model than the CoCo implementations from x86. KVM's guest_memfd is focused on providing memory that is more isolated than AVF requires. Some specific examples include ability to pre-load data onto guest-private pages, dynamically sharing/isolating guest pages without copy, and (future) migrating guest-private pages. In sum of those differences after a discussion in [1] and at PUCK, we want to try to stick with existing shmem and extend GUP to support the isolation needs for arm64 pKVM and Gunyah. To that end, we introduce the concept of "exclusive GUP pinning", which enforces that only one pin of any kind is allowed when using the FOLL_EXCLUSIVE flag is set. This behavior doesn't affect FOLL_GET or any other folio refcount operations that don't go through the FOLL_PIN path. [1]: https://lore.kernel.org/all/20240319143119.GA2736@willie-the-truck/ Tree with patches at: https://git.codelinaro.org/clo/linux-kernel/gunyah-linux/-/tree/sent/exclus… anup(a)brainfault.org, paul.walmsley(a)sifive.com, palmer(a)dabbelt.com, aou(a)eecs.berkeley.edu, seanjc(a)google.com, viro(a)zeniv.linux.org.uk, brauner(a)kernel.org, willy(a)infradead.org, akpm(a)linux-foundation.org, xiaoyao.li(a)intel.com, yilun.xu(a)intel.com, chao.p.peng(a)linux.intel.com, jarkko(a)kernel.org, amoorthy(a)google.com, dmatlack(a)google.com, yu.c.zhang(a)linux.intel.com, isaku.yamahata(a)intel.com, mic(a)digikod.net, vbabka(a)suse.cz, vannapurve(a)google.com, ackerleytng(a)google.com, mail(a)maciej.szmigiero.name, david(a)redhat.com, michael.roth(a)amd.com, wei.w.wang(a)intel.com, liam.merwick(a)oracle.com, isaku.yamahata(a)gmail.com, kirill.shutemov(a)linux.intel.com, suzuki.poulose(a)arm.com, steven.price(a)arm.com, quic_eberman(a)quicinc.com, quic_mnalajal(a)quicinc.com, quic_tsoni(a)quicinc.com, quic_svaddagi(a)quicinc.com, quic_cvanscha(a)quicinc.com, quic_pderrin(a)quicinc.com, quic_pheragu(a)quicinc.com, catalin.marinas(a)arm.com, james.morse(a)arm.com, yuzenghui(a)huawei.com, oliver.upton(a)linux.dev, maz(a)kernel.org, will(a)kernel.org, qperret(a)google.com, keirf(a)google.com, tabba(a)google.com Signed-off-by: Elliot Berman <quic_eberman(a)quicinc.com> --- Elliot Berman (2): mm/gup-test: Verify exclusive pinned mm/gup_test: Verify GUP grabs same pages twice Fuad Tabba (3): mm/gup: Move GUP_PIN_COUNTING_BIAS to page_ref.h mm/gup: Add an option for obtaining an exclusive pin mm/gup: Add support for re-pinning a normal pinned page as exclusive include/linux/mm.h | 57 ++++---- include/linux/mm_types.h | 2 + include/linux/page_ref.h | 74 ++++++++++ mm/Kconfig | 5 + mm/gup.c | 265 ++++++++++++++++++++++++++++++---- mm/gup_test.c | 108 ++++++++++++++ mm/gup_test.h | 1 + tools/testing/selftests/mm/gup_test.c | 5 +- 8 files changed, 457 insertions(+), 60 deletions(-) --- base-commit: 6ba59ff4227927d3a8530fc2973b80e94b54d58f change-id: 20240509-exclusive-gup-66259138bbff Best regards, -- Elliot Berman <quic_eberman(a)quicinc.com>

4 months, 2 weeks

13
68
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[PATCH 0/2] selftests/nolibc: run-user improvements

by Thomas Weißschuh

A small bugfix for "run-user XARCH=ppc64le" and run-user support for run-tests.sh. Signed-off-by: Thomas Weißschuh <linux(a)weissschuh.net> --- Thomas Weißschuh (2): selftests/nolibc: introduce QEMU_ARCH_USER selftests/nolibc: run-tests.sh: enable testing via qemu-user tools/testing/selftests/nolibc/Makefile | 5 ++++- tools/testing/selftests/nolibc/run-tests.sh | 22 +++++++++++++++++++--- 2 files changed, 23 insertions(+), 4 deletions(-) --- base-commit: ba335752620565c25c3028fff9496bb8ef373602 change-id: 20770915-nolibc-run-user-845375a3ec4f Best regards, -- Thomas Weißschuh <linux(a)weissschuh.net>

4 months, 3 weeks

5
8
0 0

[PATCH 0/1] selftest: drivers: Add support its msi hwirq checking

by Joseph Jang

In order to validate ITS-MSI hwirq entry in the /proc/interrupts, we have created a shell script to check is there any duplicated ITS-MSI hwirq entry. Joseph Jang (1): selftest: drivers: Add support its msi hwirq checking tools/testing/selftests/drivers/irq/Makefile | 5 +++++ .../selftests/drivers/irq/its-msi-irq-test.sh | 20 +++++++++++++++++++ 2 files changed, 25 insertions(+) create mode 100644 tools/testing/selftests/drivers/irq/Makefile create mode 100755 tools/testing/selftests/drivers/irq/its-msi-irq-test.sh -- 2.34.1

4 months, 3 weeks

4
5
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[RFC PATCH v5 00/29] TDX KVM selftests

by Sagi Shahar

Hello, This is v4 of the patch series for TDX selftests. It has been updated for Intel’s v17 of the TDX host patches which was proposed here: https://lore.kernel.org/all/cover.1699368322.git.isaku.yamahata@intel.com/ The tree can be found at: https://github.com/googleprodkernel/linux-cc/tree/tdx-selftests-rfc-v5 Changes from RFC v4: Added patch to propagate KVM_EXIT_MEMORY_FAULT to userspace. Minor tweaks to align the tests to the new TDX 1.5 spec such as changes in the expected values in TDG.VP.INFO. In RFCv5, TDX selftest code is organized into: + headers in tools/testing/selftests/kvm/include/x86_64/tdx/ + common code in tools/testing/selftests/kvm/lib/x86_64/tdx/ + selftests in tools/testing/selftests/kvm/x86_64/tdx_* Dependencies + Peter’s patches, which provide functions for the host to allocate and track protected memory in the guest. https://lore.kernel.org/all/20230110175057.715453-1-pgonda@google.com/ Further work for this patch series/TODOs + Sean’s comments for the non-confidential UPM selftests patch series at https://lore.kernel.org/lkml/Y8dC8WDwEmYixJqt@google.com/T/#u apply here as well + Add ucall support for TDX selftests I would also like to acknowledge the following people, who helped review or test patches in previous versions: + Sean Christopherson <seanjc(a)google.com> + Zhenzhong Duan <zhenzhong.duan(a)intel.com> + Peter Gonda <pgonda(a)google.com> + Andrew Jones <drjones(a)redhat.com> + Maxim Levitsky <mlevitsk(a)redhat.com> + Xiaoyao Li <xiaoyao.li(a)intel.com> + David Matlack <dmatlack(a)google.com> + Marc Orr <marcorr(a)google.com> + Isaku Yamahata <isaku.yamahata(a)gmail.com> + Maciej S. Szmigiero <maciej.szmigiero(a)oracle.com> Links to earlier patch series + RFC v1: https://lore.kernel.org/lkml/20210726183816.1343022-1-erdemaktas@google.com… + RFC v2: https://lore.kernel.org/lkml/20220830222000.709028-1-sagis@google.com/T/#u + RFC v3: https://lore.kernel.org/lkml/20230121001542.2472357-1-ackerleytng@google.co… + RFC v4: https://lore.kernel.org/lkml/20230725220132.2310657-1-afranji@google.com/ *** BLURB HERE *** Ackerley Tng (12): KVM: selftests: Add function to allow one-to-one GVA to GPA mappings KVM: selftests: Expose function that sets up sregs based on VM's mode KVM: selftests: Store initial stack address in struct kvm_vcpu KVM: selftests: Refactor steps in vCPU descriptor table initialization KVM: selftests: TDX: Use KVM_TDX_CAPABILITIES to validate TDs' attribute configuration KVM: selftests: TDX: Update load_td_memory_region for VM memory backed by guest memfd KVM: selftests: Add functions to allow mapping as shared KVM: selftests: Expose _vm_vaddr_alloc KVM: selftests: TDX: Add support for TDG.MEM.PAGE.ACCEPT KVM: selftests: TDX: Add support for TDG.VP.VEINFO.GET KVM: selftests: TDX: Add TDX UPM selftest KVM: selftests: TDX: Add TDX UPM selftests for implicit conversion Erdem Aktas (3): KVM: selftests: Add helper functions to create TDX VMs KVM: selftests: TDX: Add TDX lifecycle test KVM: selftests: TDX: Adding test case for TDX port IO Roger Wang (1): KVM: selftests: TDX: Add TDG.VP.INFO test Ryan Afranji (2): KVM: selftests: TDX: Verify the behavior when host consumes a TD private memory KVM: selftests: TDX: Add shared memory test Sagi Shahar (11): KVM: selftests: TDX: Add report_fatal_error test KVM: selftests: TDX: Add basic TDX CPUID test KVM: selftests: TDX: Add basic get_td_vmcall_info test KVM: selftests: TDX: Add TDX IO writes test KVM: selftests: TDX: Add TDX IO reads test KVM: selftests: TDX: Add TDX MSR read/write tests KVM: selftests: TDX: Add TDX HLT exit test KVM: selftests: TDX: Add TDX MMIO reads test KVM: selftests: TDX: Add TDX MMIO writes test KVM: selftests: TDX: Add TDX CPUID TDVMCALL test KVM: selftests: Propagate KVM_EXIT_MEMORY_FAULT to userspace tools/testing/selftests/kvm/Makefile | 8 + .../selftests/kvm/include/kvm_util_base.h | 30 + .../selftests/kvm/include/x86_64/processor.h | 4 + .../kvm/include/x86_64/tdx/td_boot.h | 82 + .../kvm/include/x86_64/tdx/td_boot_asm.h | 16 + .../selftests/kvm/include/x86_64/tdx/tdcall.h | 59 + .../selftests/kvm/include/x86_64/tdx/tdx.h | 65 + .../kvm/include/x86_64/tdx/tdx_util.h | 19 + .../kvm/include/x86_64/tdx/test_util.h | 164 ++ tools/testing/selftests/kvm/lib/kvm_util.c | 101 +- .../selftests/kvm/lib/x86_64/processor.c | 77 +- .../selftests/kvm/lib/x86_64/tdx/td_boot.S | 101 ++ .../selftests/kvm/lib/x86_64/tdx/tdcall.S | 158 ++ .../selftests/kvm/lib/x86_64/tdx/tdx.c | 262 ++++ .../selftests/kvm/lib/x86_64/tdx/tdx_util.c | 558 +++++++ .../selftests/kvm/lib/x86_64/tdx/test_util.c | 101 ++ .../kvm/x86_64/tdx_shared_mem_test.c | 135 ++ .../selftests/kvm/x86_64/tdx_upm_test.c | 469 ++++++ .../selftests/kvm/x86_64/tdx_vm_tests.c | 1319 +++++++++++++++++ 19 files changed, 3693 insertions(+), 35 deletions(-) create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/td_boot.h create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/td_boot_asm.h create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/td_boot.S create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_shared_mem_test.c create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_upm_test.c create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c -- 2.43.0.472.g3155946c3a-goog

4 months, 3 weeks

10
105
0 0

[PATCH v5 0/5] pids controller events rework

by Michal Koutný

This makes pids.events:max affine to pids.max limit. How are the new events supposed to be useful? - pids.events.local:max - tells that cgroup's limit is hit (too tight?) - pids.events:* - "only" directs top-down search to cgroups of interest Changes from v4 (https://lore.kernel.org/r/20240416142014.27630-1-mkoutny@suse.com) - rebased on cgroup/for-6.10 (rather cgroup/for-next, there's no rush) - introduce pids_files_legacy at one place (Tejun) - more descriptive Documentation/ (Tejun) Changes from v3 (https://lore.kernel.org/r/20240405170548.15234-1-mkoutny@suse.com) - use existing functions for TAP output in selftest (Muhammad) - formatting in selftest (Muhammad) - remove pids.events:max.imposed event, keep it internal (Johannes) - allow legacy behavior with a mount option - detach migration charging patches - drop RFC prefix Changes from v2 (https://lore.kernel.org/r/20200205134426.10570-1-mkoutny@suse.com) - implemented pids.events.local (Tejun) - added migration charging [1] https://lore.kernel.org/r/20230202155626.1829121-1-hannes@cmpxchg.org/ Michal Koutný (5): cgroup/pids: Separate semantics of pids.events related to pids.max cgroup/pids: Make event counters hierarchical cgroup/pids: Add pids.events.local selftests: cgroup: Lexicographic order in Makefile selftests: cgroup: Add basic tests for pids controller Documentation/admin-guide/cgroup-v1/pids.rst | 3 +- Documentation/admin-guide/cgroup-v2.rst | 21 ++- include/linux/cgroup-defs.h | 7 +- kernel/cgroup/cgroup.c | 15 +- kernel/cgroup/pids.c | 129 +++++++++++--- tools/testing/selftests/cgroup/.gitignore | 11 +- tools/testing/selftests/cgroup/Makefile | 25 +-- tools/testing/selftests/cgroup/test_pids.c | 178 +++++++++++++++++++ 8 files changed, 346 insertions(+), 43 deletions(-) create mode 100644 tools/testing/selftests/cgroup/test_pids.c base-commit: 21c38a3bd4ee3fb7337d013a638302fb5e5f9dc2 -- 2.44.0

4 months, 3 weeks

4
10
0 0

[PATCH net-next v15 00/14] Device Memory TCP

by Mina Almasry

v15: https://patchwork.kernel.org/project/netdevbpf/list/?series=865481&state=* ==== No material changes in this version, only a fix to linking against libynl.a from the last version. Per Jakub's instructions I've pulled one of his patches into this series, and now use the new libynl.a correctly, I hope. As usual, the full devmem TCP changes including the full GVE driver implementation is here: https://github.com/mina/linux/commits/tcpdevmem-v15/ v14: https://patchwork.kernel.org/project/netdevbpf/list/?series=865135&archive=… ==== No material changes in this version. Only rebase and re-verification on top of net-next. v13, I think, raced with commit ebad6d0334793 ("net/ipv4: Use nested-BH locking for ipv4_tcp_sk.") being merged to net-next that caused a patchwork failure to apply. This series should apply cleanly on commit c4532232fa2a4 ("selftests: net: remove unneeded IP_GRE config"). I did not wait the customary 24hr as Jakub said it's OK to repost as soon as I build test the rebased version: https://lore.kernel.org/netdev/20240625075926.146d769d@kernel.org/ v13: https://patchwork.kernel.org/project/netdevbpf/list/?series=861406&archive=… ==== Major changes: -------------- This iteration addresses Pavel's review comments, applies his reviewed-by's, and seeks to fix the patchwork build error (sorry!). As usual, the full devmem TCP changes including the full GVE driver implementation is here: https://github.com/mina/linux/commits/tcpdevmem-v13/ v12: https://patchwork.kernel.org/project/netdevbpf/list/?series=859747&state=* ==== Major changes: -------------- This iteration only addresses one minor comment from Pavel with regards to the trace printing of netmem, and the patchwork build error introduced in v11 because I missed doing an allmodconfig build, sorry. Other than that v11, AFAICT, received no feedback. There is one discussion about how the specifics of plugging io uring memory through the page pool, but not relevant to content in this particular patchset, AFAICT. As usual, the full devmem TCP changes including the full GVE driver implementation is here: https://github.com/mina/linux/commits/tcpdevmem-v12/ v11: https://patchwork.kernel.org/project/netdevbpf/list/?series=857457&state=* ==== Major Changes: -------------- v11 addresses feedback received in v10. The major change is the removal of the memory provider ops as requested by Christoph. We still accomplish the same thing, but utilizing direct function calls with if statements rather than generic ops. Additionally address sparse warnings, bugs and review comments from folks that reviewed. As usual, the full devmem TCP changes including the full GVE driver implementation is here: https://github.com/mina/linux/commits/tcpdevmem-v11/ Detailed changelog: ------------------- - Fixes in netdev_rx_queue_restart() from Pavel & David. - Remove commit e650e8c3a36f5 ("net: page_pool: create hooks for custom page providers") from the series to address Christoph's feedback and rebased other patches on the series on this change. - Fixed build errors with CONFIG_DMA_SHARED_BUFFER && !CONFIG_GENERIC_ALLOCATOR build. - Fixed sparse warnings pointed out by Paolo. - Drop unnecessary gro_pull_from_frag0 checks. - Added Bagas reviewed-by to docs. Cc: Bagas Sanjaya <bagasdotme(a)gmail.com> Cc: Steven Rostedt <rostedt(a)goodmis.org> Cc: Christoph Hellwig <hch(a)infradead.org> Cc: Nikolay Aleksandrov <razor(a)blackwall.org> v10: https://patchwork.kernel.org/project/netdevbpf/list/?series=852422&state=* ==== Major Changes: -------------- v9 was sent right before the merge window closed (sorry!). v10 is almost a re-send of the series now that the merge window re-opened. Only rebased to latest net-next and addressed some minor iterative comments received on v9. As usual, the full devmem TCP changes including the full GVE driver implementation is here: https://github.com/mina/linux/commits/tcpdevmem-v10/ Detailed changelog: ------------------- - Fixed tokens leaking in DONTNEED setsockopt (Nikolay). - Moved net_iov_dma_addr() to devmem.c and made it a devmem specific helpers (David). - Rename hook alloc_pages to alloc_netmems as alloc_pages is now preprocessor macro defined and causes a build error. v9: === Major Changes: -------------- GVE queue API has been merged. Submitting this version as non-RFC after rebasing on top of the merged API, and dropped the out of tree queue API I was carrying on github. Addressed the little feedback v8 has received. Detailed changelog: ------------------ - Added new patch from David Wei to this series for netdev_rx_queue_restart() - Fixed sparse error. - Removed CONFIG_ checks in netmem_is_net_iov() - Flipped skb->readable to skb->unreadable - Minor fixes to selftests & docs. RFC v8: ======= Major Changes: -------------- - Fixed build error generated by patch-by-patch build. - Applied docs suggestions from Randy. RFC v7: ======= Major Changes: -------------- This revision largely rebases on top of net-next and addresses the feedback RFCv6 received from folks, namely Jakub, Yunsheng, Arnd, David, & Pavel. The series remains in RFC because the queue-API ndos defined in this series are not yet implemented. I have a GVE implementation I carry out of tree for my testing. A upstreamable GVE implementation is in the works. Aside from that, in my estimation all the patches are ready for review/merge. Please do take a look. As usual the full devmem TCP changes including the full GVE driver implementation is here: https://github.com/mina/linux/commits/tcpdevmem-v7/ Detailed changelog: - Use admin-perm in netlink API. - Addressed feedback from Jakub with regards to netlink API implementation. - Renamed devmem.c functions to something more appropriate for that file. - Improve the performance seen through the page_pool benchmark. - Fix the value definition of all the SO_DEVMEM_* uapi. - Various fixes to documentation. Perf - page-pool benchmark: --------------------------- Improved performance of bench_page_pool_simple.ko tests compared to v6: https://pastebin.com/raw/v5dYRg8L net-next base: 8 cycle fast path. RFC v6: 10 cycle fast path. RFC v7: 9 cycle fast path. RFC v7 with CONFIG_DMA_SHARED_BUFFER disabled: 8 cycle fast path, same as baseline. Perf - Devmem TCP benchmark: --------------------- Perf is about the same regardless of the changes in v7, namely the removal of the static_branch_unlikely to improve the page_pool benchmark performance: 189/200gbps bi-directional throughput with RX devmem TCP and regular TCP TX i.e. ~95% line rate. RFC v6: ======= Major Changes: -------------- This revision largely rebases on top of net-next and addresses the little feedback RFCv5 received. The series remains in RFC because the queue-API ndos defined in this series are not yet implemented. I have a GVE implementation I carry out of tree for my testing. A upstreamable GVE implementation is in the works. Aside from that, in my estimation all the patches are ready for review/merge. Please do take a look. As usual the full devmem TCP changes including the full GVE driver implementation is here: https://github.com/mina/linux/commits/tcpdevmem-v6/ This version also comes with some performance data recorded in the cover letter (see below changelog). Detailed changelog: - Rebased on top of the merged netmem_ref changes. - Converted skb->dmabuf to skb->readable (Pavel). Pavel's original suggestion was to remove the skb->dmabuf flag entirely, but when I looked into it closely, I found the issue that if we remove the flag we have to dereference the shinfo(skb) pointer to obtain the first frag to tell whether an skb is readable or not. This can cause a performance regression if it dirties the cache line when the shinfo(skb) was not really needed. Instead, I converted the skb->dmabuf flag into a generic skb->readable flag which can be re-used by io_uring 0-copy RX. - Squashed a few locking optimizations from Eric Dumazet in the RX path and the DEVMEM_DONTNEED setsockopt. - Expanded the tests a bit. Added validation for invalid scenarios and added some more coverage. Perf - page-pool benchmark: --------------------------- bench_page_pool_simple.ko tests with and without these changes: https://pastebin.com/raw/ncHDwAbn AFAIK the number that really matters in the perf tests is the 'tasklet_page_pool01_fast_path Per elem'. This one measures at about 8 cycles without the changes but there is some 1 cycle noise in some results. With the patches this regresses to 9 cycles with the changes but there is 1 cycle noise occasionally running this test repeatedly. Lastly I tried disable the static_branch_unlikely() in netmem_is_net_iov() check. To my surprise disabling the static_branch_unlikely() check reduces the fast path back to 8 cycles, but the 1 cycle noise remains. Perf - Devmem TCP benchmark: --------------------- 189/200gbps bi-directional throughput with RX devmem TCP and regular TCP TX i.e. ~95% line rate. Major changes in RFC v5: ======================== 1. Rebased on top of 'Abstract page from net stack' series and used the new netmem type to refer to LSB set pointers instead of re-using struct page. 2. Downgraded this series back to RFC and called it RFC v5. This is because this series is now dependent on 'Abstract page from net stack'[1] and the queue API. Both are removed from the series to reduce the patch # and those bits are fairly independent or pre-requisite work. 3. Reworked the page_pool devmem support to use netmem and for some more unified handling. 4. Reworked the reference counting of net_iov (renamed from page_pool_iov) to use pp_ref_count for refcounting. The full changes including the dependent series and GVE page pool support is here: https://github.com/mina/linux/commits/tcpdevmem-rfcv5/ [1] https://patchwork.kernel.org/project/netdevbpf/list/?series=810774 Major changes in v1: ==================== 1. Implemented MVP queue API ndos to remove the userspace-visible driver reset. 2. Fixed issues in the napi_pp_put_page() devmem frag unref path. 3. Removed RFC tag. Many smaller addressed comments across all the patches (patches have individual change log). Full tree including the rest of the GVE driver changes: https://github.com/mina/linux/commits/tcpdevmem-v1 Changes in RFC v3: ================== 1. Pulled in the memory-provider dependency from Jakub's RFC[1] to make the series reviewable and mergeable. 2. Implemented multi-rx-queue binding which was a todo in v2. 3. Fix to cmsg handling. The sticking point in RFC v2[2] was the device reset required to refill the device rx-queues after the dmabuf bind/unbind. The solution suggested as I understand is a subset of the per-queue management ops Jakub suggested or similar: https://lore.kernel.org/netdev/20230815171638.4c057dcd@kernel.org/ This is not addressed in this revision, because: 1. This point was discussed at netconf & netdev and there is openness to using the current approach of requiring a device reset. 2. Implementing individual queue resetting seems to be difficult for my test bed with GVE. My prototype to test this ran into issues with the rx-queues not coming back up properly if reset individually. At the moment I'm unsure if it's a mistake in the POC or a genuine issue in the virtualization stack behind GVE, which currently doesn't test individual rx-queue restart. 3. Our usecases are not bothered by requiring a device reset to refill the buffer queues, and we'd like to support NICs that run into this limitation with resetting individual queues. My thought is that drivers that have trouble with per-queue configs can use the support in this series, while drivers that support new netdev ops to reset individual queues can automatically reset the queue as part of the dma-buf bind/unbind. The same approach with device resets is presented again for consideration with other sticking points addressed. This proposal includes the rx devmem path only proposed for merge. For a snapshot of my entire tree which includes the GVE POC page pool support & device memory support: https://github.com/torvalds/linux/compare/master...mina:linux:tcpdevmem-v3 [1] https://lore.kernel.org/netdev/f8270765-a27b-6ccf-33ea-cda097168d79@redhat.… [2] https://lore.kernel.org/netdev/CAHS8izOVJGJH5WF68OsRWFKJid1_huzzUK+hpKbLcL4… Changes in RFC v2: ================== The sticking point in RFC v1[1] was the dma-buf pages approach we used to deliver the device memory to the TCP stack. RFC v2 is a proof-of-concept that attempts to resolve this by implementing scatterlist support in the networking stack, such that we can import the dma-buf scatterlist directly. This is the approach proposed at a high level here[2]. Detailed changes: 1. Replaced dma-buf pages approach with importing scatterlist into the page pool. 2. Replace the dma-buf pages centric API with a netlink API. 3. Removed the TX path implementation - there is no issue with implementing the TX path with scatterlist approach, but leaving out the TX path makes it easier to review. 4. Functionality is tested with this proposal, but I have not conducted perf testing yet. I'm not sure there are regressions, but I removed perf claims from the cover letter until they can be re-confirmed. 5. Added Signed-off-by: contributors to the implementation. 6. Fixed some bugs with the RX path since RFC v1. Any feedback welcome, but specifically the biggest pending questions needing feedback IMO are: 1. Feedback on the scatterlist-based approach in general. 2. Netlink API (Patch 1 & 2). 3. Approach to handle all the drivers that expect to receive pages from the page pool (Patch 6). [1] https://lore.kernel.org/netdev/dfe4bae7-13a0-3c5d-d671-f61b375cb0b4@gmail.c… [2] https://lore.kernel.org/netdev/CAHS8izPm6XRS54LdCDZVd0C75tA1zHSu6jLVO8nzTLX… ================== * TL;DR: Device memory TCP (devmem TCP) is a proposal for transferring data to and/or from device memory efficiently, without bouncing the data to a host memory buffer. * Problem: A large amount of data transfers have device memory as the source and/or destination. Accelerators drastically increased the volume of such transfers. Some examples include: - ML accelerators transferring large amounts of training data from storage into GPU/TPU memory. In some cases ML training setup time can be as long as 50% of TPU compute time, improving data transfer throughput & efficiency can help improving GPU/TPU utilization. - Distributed training, where ML accelerators, such as GPUs on different hosts, exchange data among them. - Distributed raw block storage applications transfer large amounts of data with remote SSDs, much of this data does not require host processing. Today, the majority of the Device-to-Device data transfers the network are implemented as the following low level operations: Device-to-Host copy, Host-to-Host network transfer, and Host-to-Device copy. The implementation is suboptimal, especially for bulk data transfers, and can put significant strains on system resources, such as host memory bandwidth, PCIe bandwidth, etc. One important reason behind the current state is the kernel’s lack of semantics to express device to network transfers. * Proposal: In this patch series we attempt to optimize this use case by implementing socket APIs that enable the user to: 1. send device memory across the network directly, and 2. receive incoming network packets directly into device memory. Packet _payloads_ go directly from the NIC to device memory for receive and from device memory to NIC for transmit. Packet _headers_ go to/from host memory and are processed by the TCP/IP stack normally. The NIC _must_ support header split to achieve this. Advantages: - Alleviate host memory bandwidth pressure, compared to existing network-transfer + device-copy semantics. - Alleviate PCIe BW pressure, by limiting data transfer to the lowest level of the PCIe tree, compared to traditional path which sends data through the root complex. * Patch overview: ** Part 1: netlink API Gives user ability to bind dma-buf to an RX queue. ** Part 2: scatterlist support Currently the standard for device memory sharing is DMABUF, which doesn't generate struct pages. On the other hand, networking stack (skbs, drivers, and page pool) operate on pages. We have 2 options: 1. Generate struct pages for dmabuf device memory, or, 2. Modify the networking stack to process scatterlist. Approach #1 was attempted in RFC v1. RFC v2 implements approach #2. ** part 3: page pool support We piggy back on page pool memory providers proposal: https://github.com/kuba-moo/linux/tree/pp-providers It allows the page pool to define a memory provider that provides the page allocation and freeing. It helps abstract most of the device memory TCP changes from the driver. ** part 4: support for unreadable skb frags Page pool iovs are not accessible by the host; we implement changes throughput the networking stack to correctly handle skbs with unreadable frags. ** Part 5: recvmsg() APIs We define user APIs for the user to send and receive device memory. Not included with this series is the GVE devmem TCP support, just to simplify the review. Code available here if desired: https://github.com/mina/linux/tree/tcpdevmem This series is built on top of net-next with Jakub's pp-providers changes cherry-picked. * NIC dependencies: 1. (strict) Devmem TCP require the NIC to support header split, i.e. the capability to split incoming packets into a header + payload and to put each into a separate buffer. Devmem TCP works by using device memory for the packet payload, and host memory for the packet headers. 2. (optional) Devmem TCP works better with flow steering support & RSS support, i.e. the NIC's ability to steer flows into certain rx queues. This allows the sysadmin to enable devmem TCP on a subset of the rx queues, and steer devmem TCP traffic onto these queues and non devmem TCP elsewhere. The NIC I have access to with these properties is the GVE with DQO support running in Google Cloud, but any NIC that supports these features would suffice. I may be able to help reviewers bring up devmem TCP on their NICs. * Testing: The series includes a udmabuf kselftest that show a simple use case of devmem TCP and validates the entire data path end to end without a dependency on a specific dmabuf provider. ** Test Setup Kernel: net-next with this series and memory provider API cherry-picked locally. Hardware: Google Cloud A3 VMs. NIC: GVE with header split & RSS & flow steering support. Cc: Pavel Begunkov <asml.silence(a)gmail.com> Cc: David Wei <dw(a)davidwei.uk> Cc: Jason Gunthorpe <jgg(a)ziepe.ca> Cc: Yunsheng Lin <linyunsheng(a)huawei.com> Cc: Shailend Chand <shailend(a)google.com> Cc: Harshitha Ramamurthy <hramamurthy(a)google.com> Cc: Shakeel Butt <shakeel.butt(a)linux.dev> Cc: Jeroen de Borst <jeroendb(a)google.com> Cc: Praveen Kaligineedi <pkaligineedi(a)google.com> Jakub Kicinski (1): tools: net: package libynl for use in selftests Mina Almasry (13): netdev: add netdev_rx_queue_restart() net: netdev netlink api to bind dma-buf to a net device netdev: support binding dma-buf to netdevice netdev: netdevice devmem allocator page_pool: convert to use netmem page_pool: devmem support memory-provider: dmabuf devmem memory provider net: support non paged skb frags net: add support for skbs with unreadable frags tcp: RX path for devmem TCP net: add SO_DEVMEM_DONTNEED setsockopt to release RX frags net: add devmem TCP documentation selftests: add ncdevmem, netcat for devmem TCP Documentation/netlink/specs/netdev.yaml | 57 +++ Documentation/networking/devmem.rst | 258 +++++++++++ Documentation/networking/index.rst | 1 + arch/alpha/include/uapi/asm/socket.h | 6 + arch/mips/include/uapi/asm/socket.h | 6 + arch/parisc/include/uapi/asm/socket.h | 6 + arch/sparc/include/uapi/asm/socket.h | 6 + include/linux/skbuff.h | 61 ++- include/linux/skbuff_ref.h | 11 +- include/linux/socket.h | 1 + include/net/devmem.h | 124 ++++++ include/net/mp_dmabuf_devmem.h | 44 ++ include/net/netdev_rx_queue.h | 5 + include/net/netmem.h | 208 ++++++++- include/net/page_pool/helpers.h | 124 ++++-- include/net/page_pool/types.h | 22 +- include/net/sock.h | 2 + include/net/tcp.h | 5 +- include/trace/events/page_pool.h | 30 +- include/uapi/asm-generic/socket.h | 6 + include/uapi/linux/netdev.h | 19 + include/uapi/linux/uio.h | 17 + net/bpf/test_run.c | 5 +- net/core/Makefile | 3 +- net/core/datagram.c | 6 + net/core/dev.c | 6 +- net/core/devmem.c | 376 ++++++++++++++++ net/core/gro.c | 3 +- net/core/netdev-genl-gen.c | 23 + net/core/netdev-genl-gen.h | 6 + net/core/netdev-genl.c | 103 +++++ net/core/netdev_rx_queue.c | 74 ++++ net/core/page_pool.c | 362 +++++++++------- net/core/skbuff.c | 83 +++- net/core/sock.c | 61 +++ net/ipv4/esp4.c | 3 +- net/ipv4/tcp.c | 261 +++++++++++- net/ipv4/tcp_input.c | 13 +- net/ipv4/tcp_ipv4.c | 16 + net/ipv4/tcp_minisocks.c | 2 + net/ipv4/tcp_output.c | 5 +- net/ipv6/esp6.c | 3 +- net/packet/af_packet.c | 4 +- tools/include/uapi/linux/netdev.h | 19 + tools/net/ynl/Makefile | 6 +- tools/net/ynl/lib/Makefile | 4 +- tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 9 + tools/testing/selftests/net/ncdevmem.c | 542 ++++++++++++++++++++++++ tools/testing/selftests/net/ynl.mk | 21 + 50 files changed, 2786 insertions(+), 253 deletions(-) create mode 100644 Documentation/networking/devmem.rst create mode 100644 include/net/devmem.h create mode 100644 include/net/mp_dmabuf_devmem.h create mode 100644 net/core/devmem.c create mode 100644 net/core/netdev_rx_queue.c create mode 100644 tools/testing/selftests/net/ncdevmem.c create mode 100644 tools/testing/selftests/net/ynl.mk -- 2.45.2.803.g4e1b14247a-goog

5 months

10
46
0 0

[PATCH v4 0/2] Add test to distinguish between thread's signal mask and ucontext_t

by Dev Jain

This patch series is motivated by the following observation: Raise a signal, jump to signal handler. The ucontext_t structure dumped by kernel to userspace has a uc_sigmask field having the mask of blocked signals. If you run a fresh minimalistic program doing this, this field is empty, even if you block some signals while registering the handler with sigaction(). Here is what the man-pages have to say: sigaction(2): "sa_mask specifies a mask of signals which should be blocked (i.e., added to the signal mask of the thread in which the signal handler is invoked) during execution of the signal handler. In addition, the signal which triggered the handler will be blocked, unless the SA_NODEFER flag is used." signal(7): Under "Execution of signal handlers", (1.3) implies: "The thread's current signal mask is accessible via the ucontext_t object that is pointed to by the third argument of the signal handler." But, (1.4) states: "Any signals specified in act->sa_mask when registering the handler with sigprocmask(2) are added to the thread's signal mask. The signal being delivered is also added to the signal mask, unless SA_NODEFER was specified when registering the handler. These signals are thus blocked while the handler executes." There clearly is no distinction being made in the man pages between "Thread's signal mask" and ucontext_t; this logically should imply that a signal blocked by populating struct sigaction should be visible in ucontext_t. Here is what the kernel code does (for Aarch64): do_signal() -> handle_signal() -> sigmask_to_save(), which returns &current->blocked, is passed to setup_rt_frame() -> setup_sigframe() -> __copy_to_user(). Hence, &current->blocked is copied to ucontext_t exposed to userspace. Returning back to handle_signal(), signal_setup_done() -> signal_delivered() -> sigorsets() and set_current_blocked() are responsible for using information from struct ksignal ksig, which was populated through the sigaction() system call in kernel/signal.c: copy_from_user(&new_sa.sa, act, sizeof(new_sa.sa)), to update &current->blocked; hence, the set of blocked signals for the current thread is updated AFTER the kernel dumps ucontext_t to userspace. Assuming that the above is indeed the intended behaviour, because it semantically makes sense, since the signals blocked using sigaction() remain blocked only till the execution of the handler, and not in the context present before jumping to the handler (but nothing can be confirmed from the man-pages), the series introduces a test for mangling with uc_sigmask. I will send a separate series to fix the man-pages. The proposed selftest has been tested out on Aarch32, Aarch64 and x86_64. v3->v4: - Allocate sigsets as automatic variables to avoid malloc() v2->v3: - ucontext describes current state -> ucontext describes interrupted context - Add a comment for blockage of USR2 even after return from handler - Describe blockage of signals in a better way v1->v2: - Replace all occurrences of SIGPIPE with SIGSEGV - Fixed a mismatch between code comment and ksft log - Add a testcase: Raise the same signal again; it must not be queued - Remove unneeded <assert.h>, <unistd.h> - Give a detailed test description in the comments; also describe the exact meaning of delivered and blocked - Handle errors for all libc functions/syscalls - Mention tests in Makefile and .gitignore in alphabetical order v1: - https://lore.kernel.org/all/20240607122319.768640-1-dev.jain@arm.com/ Dev Jain (2): selftests: Rename sigaltstack to generic signal selftests: Add a test mangling with uc_sigmask tools/testing/selftests/Makefile | 2 +- .../{sigaltstack => signal}/.gitignore | 3 +- .../{sigaltstack => signal}/Makefile | 3 +- .../current_stack_pointer.h | 0 .../selftests/signal/mangle_uc_sigmask.c | 186 ++++++++++++++++++ .../sas.c => signal/sigaltstack.c} | 0 6 files changed, 191 insertions(+), 3 deletions(-) rename tools/testing/selftests/{sigaltstack => signal}/.gitignore (57%) rename tools/testing/selftests/{sigaltstack => signal}/Makefile (53%) rename tools/testing/selftests/{sigaltstack => signal}/current_stack_pointer.h (100%) create mode 100644 tools/testing/selftests/signal/mangle_uc_sigmask.c rename tools/testing/selftests/{sigaltstack/sas.c => signal/sigaltstack.c} (100%) -- 2.34.1

5 months

4
9
0 0

[PATCH v9 00/39] arm64/gcs: Provide support for GCS in userspace

by Mark Brown

The arm64 Guarded Control Stack (GCS) feature provides support for hardware protected stacks of return addresses, intended to provide hardening against return oriented programming (ROP) attacks and to make it easier to gather call stacks for applications such as profiling. When GCS is active a secondary stack called the Guarded Control Stack is maintained, protected with a memory attribute which means that it can only be written with specific GCS operations. The current GCS pointer can not be directly written to by userspace. When a BL is executed the value stored in LR is also pushed onto the GCS, and when a RET is executed the top of the GCS is popped and compared to LR with a fault being raised if the values do not match. GCS operations may only be performed on GCS pages, a data abort is generated if they are not. The combination of hardware enforcement and lack of extra instructions in the function entry and exit paths should result in something which has less overhead and is more difficult to attack than a purely software implementation like clang's shadow stacks. This series implements support for use of GCS by userspace, along with support for use of GCS within KVM guests. It does not enable use of GCS by either EL1 or EL2, this will be implemented separately. Executables are started without GCS and must use a prctl() to enable it, it is expected that this will be done very early in application execution by the dynamic linker or other startup code. For dynamic linking this will be done by checking that everything in the executable is marked as GCS compatible. x86 has an equivalent feature called shadow stacks, this series depends on the x86 patches for generic memory management support for the new guarded/shadow stack page type and shares APIs as much as possible. As there has been extensive discussion with the wider community around the ABI for shadow stacks I have as far as practical kept implementation decisions close to those for x86, anticipating that review would lead to similar conclusions in the absence of strong reasoning for divergence. The main divergence I am concious of is that x86 allows shadow stack to be enabled and disabled repeatedly, freeing the shadow stack for the thread whenever disabled, while this implementation keeps the GCS allocated after disable but refuses to reenable it. This is to avoid races with things actively walking the GCS during a disable, we do anticipate that some systems will wish to disable GCS at runtime but are not aware of any demand for subsequently reenabling it. x86 uses an arch_prctl() to manage enable and disable, since only x86 and S/390 use arch_prctl() a generic prctl() was proposed[1] as part of a patch set for the equivalent RISC-V Zicfiss feature which I initially adopted fairly directly but following review feedback has been revised quite a bit. We currently maintain the x86 pattern of implicitly allocating a shadow stack for threads started with shadow stack enabled, there has been some discussion of removing this support and requiring the use of clone3() with explicit allocation of shadow stacks instead. I have no strong feelings either way, implicit allocation is not really consistent with anything else we do and creates the potential for errors around thread exit but on the other hand it is existing ABI on x86 and minimises the changes needed in userspace code. glibc and bionic changes using this ABI have been implemented and tested. Headless Android systems have been validated and Ross Burton has used this code has been used to bring up a Yocto system with GCS enabed as standard, a test implementation of V8 support has also been done. There is an open issue with support for CRIU, on x86 this required the ability to set the GCS mode via ptrace. This series supports configuring mode bits other than enable/disable via ptrace but it needs to be confirmed if this is sufficient. The series depends on support for shadow stacks in clone3(), that series includes the addition of ARCH_HAS_USER_SHADOW_STACK. https://lore.kernel.org/r/20240623-clone3-shadow-stack-v6-0-9ee7783b1fb9@ke… You can see a branch with the full set of dependencies against Linus' tree at: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git arm64-gcs [1] https://lore.kernel.org/lkml/20230213045351.3945824-1-debug@rivosinc.com/ Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v9: - Rebase onto v6.10-rc3. - Restructure and clarify memory management fault handling. - Fix up basic-gcs for the latest clone3() changes. - Convert to newly merged KVM ID register based feature configuration. - Fixes for NV traps. - Link to v8: https://lore.kernel.org/r/20240203-arm64-gcs-v8-0-c9fec77673ef@kernel.org Changes in v8: - Invalidate signal cap token on stack when consuming. - Typo and other trivial fixes. - Don't try to use process_vm_write() on GCS, it intentionally does not work. - Fix leak of thread GCSs. - Rebase onto latest clone3() series. - Link to v7: https://lore.kernel.org/r/20231122-arm64-gcs-v7-0-201c483bd775@kernel.org Changes in v7: - Rebase onto v6.7-rc2 via the clone3() patch series. - Change the token used to cap the stack during signal handling to be compatible with GCSPOPM. - Fix flags for new page types. - Fold in support for clone3(). - Replace copy_to_user_gcs() with put_user_gcs(). - Link to v6: https://lore.kernel.org/r/20231009-arm64-gcs-v6-0-78e55deaa4dd@kernel.org Changes in v6: - Rebase onto v6.6-rc3. - Add some more gcsb_dsync() barriers following spec clarifications. - Due to ongoing discussion around clone()/clone3() I've not updated anything there, the behaviour is the same as on previous versions. - Link to v5: https://lore.kernel.org/r/20230822-arm64-gcs-v5-0-9ef181dd6324@kernel.org Changes in v5: - Don't map any permissions for user GCSs, we always use EL0 accessors or use a separate mapping of the page. - Reduce the standard size of the GCS to RLIMIT_STACK/2. - Enforce a PAGE_SIZE alignment requirement on map_shadow_stack(). - Clarifications and fixes to documentation. - More tests. - Link to v4: https://lore.kernel.org/r/20230807-arm64-gcs-v4-0-68cfa37f9069@kernel.org Changes in v4: - Implement flags for map_shadow_stack() allowing the cap and end of stack marker to be enabled independently or not at all. - Relax size and alignment requirements for map_shadow_stack(). - Add more blurb explaining the advantages of hardware enforcement. - Link to v3: https://lore.kernel.org/r/20230731-arm64-gcs-v3-0-cddf9f980d98@kernel.org Changes in v3: - Rebase onto v6.5-rc4. - Add a GCS barrier on context switch. - Add a GCS stress test. - Link to v2: https://lore.kernel.org/r/20230724-arm64-gcs-v2-0-dc2c1d44c2eb@kernel.org Changes in v2: - Rebase onto v6.5-rc3. - Rework prctl() interface to allow each bit to be locked independently. - map_shadow_stack() now places the cap token based on the size requested by the caller not the actual space allocated. - Mode changes other than enable via ptrace are now supported. - Expand test coverage. - Various smaller fixes and adjustments. - Link to v1: https://lore.kernel.org/r/20230716-arm64-gcs-v1-0-bf567f93bba6@kernel.org --- Mark Brown (39): arm64/mm: Restructure arch_validate_flags() for extensibility prctl: arch-agnostic prctl for shadow stack mman: Add map_shadow_stack() flags arm64: Document boot requirements for Guarded Control Stacks arm64/gcs: Document the ABI for Guarded Control Stacks arm64/sysreg: Add definitions for architected GCS caps arm64/gcs: Add manual encodings of GCS instructions arm64/gcs: Provide put_user_gcs() arm64/cpufeature: Runtime detection of Guarded Control Stack (GCS) arm64/mm: Allocate PIE slots for EL0 guarded control stack mm: Define VM_SHADOW_STACK for arm64 when we support GCS arm64/mm: Map pages for guarded control stack KVM: arm64: Manage GCS registers for guests arm64/gcs: Allow GCS usage at EL0 and EL1 arm64/idreg: Add overrride for GCS arm64/hwcap: Add hwcap for GCS arm64/traps: Handle GCS exceptions arm64/mm: Handle GCS data aborts arm64/gcs: Context switch GCS state for EL0 arm64/gcs: Ensure that new threads have a GCS arm64/gcs: Implement shadow stack prctl() interface arm64/mm: Implement map_shadow_stack() arm64/signal: Set up and restore the GCS context for signal handlers arm64/signal: Expose GCS state in signal frames arm64/ptrace: Expose GCS via ptrace and core files arm64: Add Kconfig for Guarded Control Stack (GCS) kselftest/arm64: Verify the GCS hwcap kselftest: Provide shadow stack enable helpers for arm64 selftests/clone3: Enable arm64 shadow stack testing kselftest/arm64: Add GCS as a detected feature in the signal tests kselftest/arm64: Add framework support for GCS to signal handling tests kselftest/arm64: Allow signals tests to specify an expected si_code kselftest/arm64: Always run signals tests with GCS enabled kselftest/arm64: Add very basic GCS test program kselftest/arm64: Add a GCS test program built with the system libc kselftest/arm64: Add test coverage for GCS mode locking kselftest/arm64: Add GCS signal tests kselftest/arm64: Add a GCS stress test kselftest/arm64: Enable GCS for the FP stress tests Documentation/admin-guide/kernel-parameters.txt | 6 + Documentation/arch/arm64/booting.rst | 22 + Documentation/arch/arm64/elf_hwcaps.rst | 2 + Documentation/arch/arm64/gcs.rst | 233 +++++++ Documentation/arch/arm64/index.rst | 1 + Documentation/filesystems/proc.rst | 2 +- arch/arm64/Kconfig | 20 + arch/arm64/include/asm/cpufeature.h | 6 + arch/arm64/include/asm/el2_setup.h | 17 + arch/arm64/include/asm/esr.h | 28 +- arch/arm64/include/asm/exception.h | 2 + arch/arm64/include/asm/gcs.h | 107 +++ arch/arm64/include/asm/hwcap.h | 1 + arch/arm64/include/asm/kvm_host.h | 14 + arch/arm64/include/asm/mman.h | 23 +- arch/arm64/include/asm/pgtable-prot.h | 14 +- arch/arm64/include/asm/processor.h | 7 + arch/arm64/include/asm/sysreg.h | 20 + arch/arm64/include/asm/uaccess.h | 40 ++ arch/arm64/include/asm/vncr_mapping.h | 2 + arch/arm64/include/uapi/asm/hwcap.h | 1 + arch/arm64/include/uapi/asm/ptrace.h | 8 + arch/arm64/include/uapi/asm/sigcontext.h | 9 + arch/arm64/kernel/cpufeature.c | 19 + arch/arm64/kernel/cpuinfo.c | 1 + arch/arm64/kernel/entry-common.c | 23 + arch/arm64/kernel/pi/idreg-override.c | 2 + arch/arm64/kernel/process.c | 85 +++ arch/arm64/kernel/ptrace.c | 59 ++ arch/arm64/kernel/signal.c | 242 ++++++- arch/arm64/kernel/traps.c | 11 + arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 48 +- arch/arm64/kvm/sys_regs.c | 25 +- arch/arm64/mm/Makefile | 1 + arch/arm64/mm/fault.c | 43 ++ arch/arm64/mm/gcs.c | 325 +++++++++ arch/arm64/mm/mmap.c | 13 +- arch/arm64/tools/cpucaps | 1 + arch/x86/include/uapi/asm/mman.h | 3 - fs/proc/task_mmu.c | 3 + include/linux/mm.h | 16 +- include/uapi/asm-generic/mman.h | 4 + include/uapi/linux/elf.h | 1 + include/uapi/linux/prctl.h | 22 + kernel/sys.c | 30 + tools/testing/selftests/arm64/Makefile | 2 +- tools/testing/selftests/arm64/abi/hwcap.c | 19 + tools/testing/selftests/arm64/fp/assembler.h | 15 + tools/testing/selftests/arm64/fp/fpsimd-test.S | 2 + tools/testing/selftests/arm64/fp/sve-test.S | 2 + tools/testing/selftests/arm64/fp/za-test.S | 2 + tools/testing/selftests/arm64/fp/zt-test.S | 2 + tools/testing/selftests/arm64/gcs/.gitignore | 5 + tools/testing/selftests/arm64/gcs/Makefile | 24 + tools/testing/selftests/arm64/gcs/asm-offsets.h | 0 tools/testing/selftests/arm64/gcs/basic-gcs.c | 357 ++++++++++ tools/testing/selftests/arm64/gcs/gcs-locking.c | 200 ++++++ .../selftests/arm64/gcs/gcs-stress-thread.S | 311 +++++++++ tools/testing/selftests/arm64/gcs/gcs-stress.c | 532 +++++++++++++++ tools/testing/selftests/arm64/gcs/gcs-util.h | 100 +++ tools/testing/selftests/arm64/gcs/libc-gcs.c | 736 +++++++++++++++++++++ tools/testing/selftests/arm64/signal/.gitignore | 1 + .../testing/selftests/arm64/signal/test_signals.c | 17 +- .../testing/selftests/arm64/signal/test_signals.h | 6 + .../selftests/arm64/signal/test_signals_utils.c | 32 +- .../selftests/arm64/signal/test_signals_utils.h | 39 ++ .../arm64/signal/testcases/gcs_exception_fault.c | 62 ++ .../selftests/arm64/signal/testcases/gcs_frame.c | 88 +++ .../arm64/signal/testcases/gcs_write_fault.c | 67 ++ .../selftests/arm64/signal/testcases/testcases.c | 7 + .../selftests/arm64/signal/testcases/testcases.h | 1 + tools/testing/selftests/clone3/clone3_selftests.h | 26 + tools/testing/selftests/ksft_shstk.h | 37 ++ 73 files changed, 4213 insertions(+), 41 deletions(-) --- base-commit: 4c8cf8814957090ce50ad18f318f72e6fe0d1a32 change-id: 20230303-arm64-gcs-e311ab0d8729 Best regards, -- Mark Brown <broonie(a)kernel.org>

5 months

6
59
0 0

[PATCH net v3 0/2] bugfixes for skmsg

by Geliang Tang

From: Geliang Tang <tanggeliang(a)kylinos.cn> v3: - modifications that better address the root causes. - only contains the first two patches for -net. v2: - add patch 2, a new fix for sk_msg_memcopy_from_iter. - update patch 3, only test "sk->sk_prot->close" as Eric suggested. - update patch 4, use "goto err" instead of "return" as Eduard suggested. - add "fixes" tag for patch 1-3. - change subject prefixes as "bpf-next" to trigger BPF CI. - cc Loongarch maintainers too. BPF selftests seem to have not been fully tested on Loongarch. When I ran these tests on Loongarch recently, some errors occur. This patch set contains two bugfixes for skmsg. Geliang Tang (2): skmsg: prevent empty ingress skb from enqueuing skmsg: bugfix for sk_msg sge iteration net/core/skmsg.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.43.0

5 months, 1 week

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[PATCH RFT v6 0/9] fork: Support shadow stacks in clone3()

by Mark Brown

The kernel has recently added support for shadow stacks, currently x86 only using their CET feature but both arm64 and RISC-V have equivalent features (GCS and Zicfiss respectively), I am actively working on GCS[1]. With shadow stacks the hardware maintains an additional stack containing only the return addresses for branch instructions which is not generally writeable by userspace and ensures that any returns are to the recorded addresses. This provides some protection against ROP attacks and making it easier to collect call stacks. These shadow stacks are allocated in the address space of the userspace process. Our API for shadow stacks does not currently offer userspace any flexiblity for managing the allocation of shadow stacks for newly created threads, instead the kernel allocates a new shadow stack with the same size as the normal stack whenever a thread is created with the feature enabled. The stacks allocated in this way are freed by the kernel when the thread exits or shadow stacks are disabled for the thread. This lack of flexibility and control isn't ideal, in the vast majority of cases the shadow stack will be over allocated and the implicit allocation and deallocation is not consistent with other interfaces. As far as I can tell the interface is done in this manner mainly because the shadow stack patches were in development since before clone3() was implemented. Since clone3() is readily extensible let's add support for specifying a shadow stack when creating a new thread or process in a similar manner to how the normal stack is specified, keeping the current implicit allocation behaviour if one is not specified either with clone3() or through the use of clone(). The user must provide a shadow stack address and size, this must point to memory mapped for use as a shadow stackby map_shadow_stack() with a shadow stack token at the top of the stack. Please note that the x86 portions of this code are build tested only, I don't appear to have a system that can run CET avaible to me, I have done testing with an integration into my pending work for GCS. There is some possibility that the arm64 implementation may require the use of clone3() and explicit userspace allocation of shadow stacks, this is still under discussion. Please further note that the token consumption done by clone3() is not currently implemented in an atomic fashion, Rick indicated that he would look into fixing this if people are OK with the implementation. A new architecture feature Kconfig option for shadow stacks is added as here, this was suggested as part of the review comments for the arm64 GCS series and since we need to detect if shadow stacks are supported it seemed sensible to roll it in here. [1] https://lore.kernel.org/r/20231009-arm64-gcs-v6-0-78e55deaa4dd@kernel.org/ Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v6: - Rebase onto v6.10-rc3. - Ensure we don't try to free the parent shadow stack in error paths of x86 arch code. - Spelling fixes in userspace API document. - Additional cleanups and improvements to the clone3() tests to support the shadow stack tests. - Link to v5: https://lore.kernel.org/r/20240203-clone3-shadow-stack-v5-0-322c69598e4b@ke… Changes in v5: - Rebase onto v6.8-rc2. - Rework ABI to have the user allocate the shadow stack memory with map_shadow_stack() and a token. - Force inlining of the x86 shadow stack enablement. - Move shadow stack enablement out into a shared header for reuse by other tests. - Link to v4: https://lore.kernel.org/r/20231128-clone3-shadow-stack-v4-0-8b28ffe4f676@ke… Changes in v4: - Formatting changes. - Use a define for minimum shadow stack size and move some basic validation to fork.c. - Link to v3: https://lore.kernel.org/r/20231120-clone3-shadow-stack-v3-0-a7b8ed3e2acc@ke… Changes in v3: - Rebase onto v6.7-rc2. - Remove stale shadow_stack in internal kargs. - If a shadow stack is specified unconditionally use it regardless of CLONE_ parameters. - Force enable shadow stacks in the selftest. - Update changelogs for RISC-V feature rename. - Link to v2: https://lore.kernel.org/r/20231114-clone3-shadow-stack-v2-0-b613f8681155@ke… Changes in v2: - Rebase onto v6.7-rc1. - Remove ability to provide preallocated shadow stack, just specify the desired size. - Link to v1: https://lore.kernel.org/r/20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@ke… --- Mark Brown (9): Documentation: userspace-api: Add shadow stack API documentation selftests: Provide helper header for shadow stack testing mm: Introduce ARCH_HAS_USER_SHADOW_STACK fork: Add shadow stack support to clone3() selftests/clone3: Remove redundant flushes of output streams selftests/clone3: Factor more of main loop into test_clone3() selftests/clone3: Explicitly handle child exits due to signals selftests/clone3: Allow tests to flag if -E2BIG is a valid error code selftests/clone3: Test shadow stack support Documentation/userspace-api/index.rst | 1 + Documentation/userspace-api/shadow_stack.rst | 41 ++++ arch/x86/Kconfig | 1 + arch/x86/include/asm/shstk.h | 11 +- arch/x86/kernel/process.c | 2 +- arch/x86/kernel/shstk.c | 104 +++++++--- fs/proc/task_mmu.c | 2 +- include/linux/mm.h | 2 +- include/linux/sched/task.h | 13 ++ include/uapi/linux/sched.h | 13 +- kernel/fork.c | 76 ++++++-- mm/Kconfig | 6 + tools/testing/selftests/clone3/clone3.c | 225 ++++++++++++++++++---- tools/testing/selftests/clone3/clone3_selftests.h | 40 +++- tools/testing/selftests/ksft_shstk.h | 63 ++++++ 15 files changed, 512 insertions(+), 88 deletions(-) --- base-commit: 83a7eefedc9b56fe7bfeff13b6c7356688ffa670 change-id: 20231019-clone3-shadow-stack-15d40d2bf536 Best regards, -- Mark Brown <broonie(a)kernel.org>

5 months, 1 week

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