April 2025 - Linux-kselftest-mirror

[PATCH v5 00/28] KVM: arm64: Implement support for SME

by Mark Brown

I've removed the RFC tag from this version of the series, but the items that I'm looking for feedback on remains the same: - The userspace ABI, in particular: - The vector length used for the SVE registers, access to the SVE registers and access to ZA and (if available) ZT0 depending on the current state of PSTATE.{SM,ZA}. - The use of a single finalisation for both SVE and SME. - The addition of control for enabling fine grained traps in a similar manner to FGU but without the UNDEF, I'm not clear if this is desired at all and at present this requires symmetric read and write traps like FGU. That seemed like it might be desired from an implementation point of view but we already have one case where we enable an asymmetric trap (for ARM64_WORKAROUND_AMPERE_AC03_CPU_38) and it seems generally useful to enable asymmetrically. This series implements support for SME use in non-protected KVM guests. Much of this is very similar to SVE, the main additional challenge that SME presents is that it introduces a new vector length similar to the SVE vector length and two new controls which change the registers seen by guests: - PSTATE.ZA enables the ZA matrix register and, if SME2 is supported, the ZT0 LUT register. - PSTATE.SM enables streaming mode, a new floating point mode which uses the SVE register set with the separately configured SME vector length. In streaming mode implementation of the FFR register is optional. It is also permitted to build systems which support SME without SVE, in this case when not in streaming mode no SVE registers or instructions are available. Further, there is no requirement that there be any overlap in the set of vector lengths supported by SVE and SME in a system, this is expected to be a common situation in practical systems. Since there is a new vector length to configure we introduce a new feature parallel to the existing SVE one with a new pseudo register for the streaming mode vector length. Due to the overlap with SVE caused by streaming mode rather than finalising SME as a separate feature we use the existing SVE finalisation to also finalise SME, a new define KVM_ARM_VCPU_VEC is provided to help make user code clearer. Finalising SVE and SME separately would introduce complication with register access since finalising SVE makes the SVE registers writeable by userspace and doing multiple finalisations results in an error being reported. Dealing with a state where the SVE registers are writeable due to one of SVE or SME being finalised but may have their VL changed by the other being finalised seems like needless complexity with minimal practical utility, it seems clearer to just express directly that only one finalisation can be done in the ABI. Access to the floating point registers follows the architecture: - When both SVE and SME are present: - If PSTATE.SM == 0 the vector length used for the Z and P registers is the SVE vector length. - If PSTATE.SM == 1 the vector length used for the Z and P registers is the SME vector length. - If only SME is present: - If PSTATE.SM == 0 the Z and P registers are inaccessible and the floating point state accessed via the encodings for the V registers. - If PSTATE.SM == 1 the vector length used for the Z and P registers - The SME specific ZA and ZT0 registers are only accessible if SVCR.ZA is 1. The VMM must understand this, in particular when loading state SVCR should be configured before other state. It should be noted that while the architecture refers to PSTATE.SM and PSTATE.ZA these PSTATE bits are not preserved in SPSR_ELx, they are only accessible via SVCR. There are a large number of subfeatures for SME, most of which only offer additional instructions but some of which (SME2 and FA64) add architectural state. These are configured via the ID registers as per usual. Protected KVM supported, with the implementation maintaining the existing restriction that the hypervisor will refuse to run if streaming mode or ZA is enabled. This both simplfies the code and avoids the need to allocate storage for host ZA and ZT0 state, there seems to be little practical use case for supporting this and the memory usage would be non-trivial. The new KVM_ARM_VCPU_VEC feature and ZA and ZT0 registers have not been added to the get-reg-list selftest, the idea of supporting additional features there without restructuring the program to generate all possible feature combinations has been rejected. I will post a separate series which does that restructuring. This series is based on Mark Rutland's SME fixes: https://lore.kernel.org/r/20250409164010.3480271-1-mark.rutland@arm.com with a build dependency due to the first patch "arm64/fpsimd: Avoid RES0 bits in the SME trap handler" which changes the defines for ESR decode, but also due to the assistance in testing. Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v5: - Rebase onto v6.15-rc2. - Add pKVM guest support. - Always restore SVCR. - Link to v4: https://lore.kernel.org/r/20250214-kvm-arm64-sme-v4-0-d64a681adcc2@kernel.o… Changes in v4: - Rebase onto v6.14-rc2 and Mark Rutland's fixes. - Expose SME to nested guests. - Additional cleanups and test fixes following on from the rebase. - Flush register state on VMM PSTATE.{SM,ZA}. - Link to v3: https://lore.kernel.org/r/20241220-kvm-arm64-sme-v3-0-05b018c1ffeb@kernel.o… Changes in v3: - Rebase onto v6.12-rc2. - Link to v2: https://lore.kernel.org/r/20231222-kvm-arm64-sme-v2-0-da226cb180bb@kernel.o… Changes in v2: - Rebase onto v6.7-rc3. - Configure subfeatures based on host system only. - Complete nVHE support. - There was some snafu with sending v1 out, it didn't make it to the lists but in case it hit people's inboxes I'm sending as v2. --- Mark Brown (28): arm64/fpsimd: Update FA64 and ZT0 enables when loading SME state arm64/fpsimd: Decide to save ZT0 and streaming mode FFR at bind time arm64/fpsimd: Check enable bit for FA64 when saving EFI state arm64/fpsimd: Determine maximum virtualisable SME vector length KVM: arm64: Introduce non-UNDEF FGT control KVM: arm64: Pay attention to FFR parameter in SVE save and load KVM: arm64: Pull ctxt_has_ helpers to start of sysreg-sr.h KVM: arm64: Move SVE state access macros after feature test macros KVM: arm64: Rename SVE finalization constants to be more general KVM: arm64: Document the KVM ABI for SME KVM: arm64: Define internal features for SME KVM: arm64: Rename sve_state_reg_region KVM: arm64: Store vector lengths in an array KVM: arm64: Implement SME vector length configuration KVM: arm64: Support SME control registers KVM: arm64: Support TPIDR2_EL0 KVM: arm64: Support SME identification registers for guests KVM: arm64: Support SME priority registers KVM: arm64: Provide assembly for SME register access KVM: arm64: Support userspace access to streaming mode Z and P registers KVM: arm64: Flush register state on writes to SVCR.SM and SVCR.ZA KVM: arm64: Expose SME specific state to userspace KVM: arm64: Context switch SME state for guests KVM: arm64: Handle SME exceptions KVM: arm64: Expose SME to nested guests KVM: arm64: Provide interface for configuring and enabling SME for guests KVM: arm64: selftests: Add SME system registers to get-reg-list KVM: arm64: selftests: Add SME to set_id_regs test Documentation/virt/kvm/api.rst | 117 +++++++---- arch/arm64/include/asm/fpsimd.h | 26 +++ arch/arm64/include/asm/kvm_emulate.h | 12 +- arch/arm64/include/asm/kvm_host.h | 151 +++++++++++--- arch/arm64/include/asm/kvm_hyp.h | 5 +- arch/arm64/include/asm/kvm_pkvm.h | 2 +- arch/arm64/include/asm/vncr_mapping.h | 2 + arch/arm64/include/uapi/asm/kvm.h | 33 +++ arch/arm64/kernel/cpufeature.c | 2 - arch/arm64/kernel/fpsimd.c | 89 ++++---- arch/arm64/kvm/arm.c | 10 + arch/arm64/kvm/fpsimd.c | 19 +- arch/arm64/kvm/guest.c | 252 ++++++++++++++++++++--- arch/arm64/kvm/handle_exit.c | 14 ++ arch/arm64/kvm/hyp/fpsimd.S | 28 ++- arch/arm64/kvm/hyp/include/hyp/switch.h | 155 ++++++++++++-- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 97 +++++---- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 81 ++++++-- arch/arm64/kvm/hyp/nvhe/pkvm.c | 20 +- arch/arm64/kvm/hyp/nvhe/switch.c | 40 +++- arch/arm64/kvm/hyp/nvhe/sys_regs.c | 6 + arch/arm64/kvm/hyp/vhe/switch.c | 29 ++- arch/arm64/kvm/nested.c | 3 +- arch/arm64/kvm/reset.c | 156 ++++++++++---- arch/arm64/kvm/sys_regs.c | 147 +++++++++++-- include/uapi/linux/kvm.h | 1 + tools/testing/selftests/kvm/arm64/get-reg-list.c | 32 ++- tools/testing/selftests/kvm/arm64/set_id_regs.c | 30 ++- 28 files changed, 1260 insertions(+), 299 deletions(-) --- base-commit: 64e9fdfc89a76fed38d8ddeed72d42ec71957ed9 change-id: 20230301-kvm-arm64-sme-06a1246d3636 prerequisite-message-id: 20250409164010.3480271-1-mark.rutland(a)arm.com prerequisite-patch-id: dfad1ae4ce049d1d736ca20aca50e0fb685cbae6 prerequisite-patch-id: 21eadb700c14ee511b5bd1565ce30ce8c76f78ef prerequisite-patch-id: 6daeeb52bc56321d51b6a53fc865e3a7ee1a1bfa prerequisite-patch-id: d05d056d40b9058b75bf0ea16498992c678d20b8 prerequisite-patch-id: f15e7a2251d9d7ea1a55d25c414848001a012d0d prerequisite-patch-id: 76df87bbb5c827562ba81c0520819f311d68f033 prerequisite-patch-id: b9709a87d0be6b933481bfee8c07846d1425add3 prerequisite-patch-id: ce17c8279c2aaf3e3bb5ffc951907c76c43c07e8 prerequisite-patch-id: cdc6c6ab4fd899ba174cffc5b05ea5f0b76f80b5 prerequisite-patch-id: 4918ab2934b5e08faabb1ef1d540c76dc9aaa404 prerequisite-patch-id: f0455ba1dcd0dd0bb57413e68349a6547a0c8e47 prerequisite-patch-id: 14afd1fc6c49b33c5de1768ecc81138a97bd7198 prerequisite-patch-id: fbfa8e67d5ebaa2774daf8126bd8dfc7fce0fecc Best regards, -- Mark Brown <broonie(a)kernel.org>

5 months

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[PATCH] selftests/ftrace: Differentiate bash and dash in dynevent_limitations.tc

by Steven Rostedt

From: Steven Rostedt <rostedt(a)goodmis.org> bash and dash evaluate variables differently. dash will evaluate '\\' every time it is read whereas bash does not. TEST_STRING="$TEST_STRING \\$i" echo $TEST_STRING With i=123 On bash, that will print "\123" but on dash, that will print the escape sequence of \123 as the \ will be interpreted again in the echo. The dynevent_limitations.tc test created a very large list of arguments to test the maximum number of arguments to pass to the dynamic events file. It had a loop of: TEST_STRING=$1 # Acceptable for i in `seq 1 $MAX_ARGS`; do TEST_STRING="$TEST_STRING \\$i" done echo "$TEST_STRING" >> dynamic_events This worked fine on bash, but when run on dash it failed. This was due to dash interpreting the "\\$i" twice. Once when it was assigned to TEST_STRING and a second time with the echo $TEST_STRING. bash does not process the backslash more than the first time. To solve this, assign a double backslash to a variable "bs" and then echo it to "ts". If "ts" changes, it is dash, if not, it is bash. Then update "bs" accordingly, and use that to assign TEST_STRING. Now this could possibly just check if "$BASH" is defined or not, but this is testing if the issue exists and not just which shell is being used. Fixes: 581a7b26ab364 ("selftests/ftrace: Add dynamic events argument limitation test case") Reported-by: Mark Brown <broonie(a)kernel.org> Closes: https://lore.kernel.org/all/ccc40f2b-4b9e-4abd-8daf-d22fce2a86f0@sirena.org… Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> --- .../test.d/dynevent/dynevent_limitations.tc | 23 ++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc b/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc index 6b94b678741a..885631c02623 100644 --- a/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc +++ b/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc @@ -7,11 +7,32 @@ MAX_ARGS=128 EXCEED_ARGS=$((MAX_ARGS + 1)) +# bash and dash evaluate variables differently. +# dash will evaluate '\\' every time it is read whereas bash does not. +# +# TEST_STRING="$TEST_STRING \\$i" +# echo $TEST_STRING +# +# With i=123 +# On bash, that will print "\123" +# but on dash, that will print the escape sequence of \123 as the \ will +# be interpreted again in the echo. +# +# Set a variable "bs" to save a double backslash, then echo that +# to "ts" to see if $ts changed or not. If it changed, it's dash, +# if not, it's bash, and then bs can equal a single backslash. +bs='\\' +ts=`echo $bs` +if [ "$ts" = '\\' ]; then + # this is bash + bs='\' +fi + check_max_args() { # event_header TEST_STRING=$1 # Acceptable for i in `seq 1 $MAX_ARGS`; do - TEST_STRING="$TEST_STRING \\$i" + TEST_STRING="$TEST_STRING $bs$i" done echo "$TEST_STRING" >> dynamic_events echo > dynamic_events -- 2.47.2

5 months

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[PATCH net-next v8 1/9] netmem: add niov->type attribute to distinguish different net_iov types

by Mina Almasry

Later patches in the series adds TX net_iovs where there is no pp associated, so we can't rely on niov->pp->mp_ops to tell what is the type of the net_iov. Add a type enum to the net_iov which tells us the net_iov type. Signed-off-by: Mina Almasry <almasrymina(a)google.com> --- v8: - Since io_uring zcrx is now in net-next, update io_uring net_iov type setting and remove the NET_IOV_UNSPECIFIED type v7: - New patch fix iouring --- include/net/netmem.h | 11 ++++++++++- io_uring/zcrx.c | 1 + net/core/devmem.c | 3 ++- 3 files changed, 13 insertions(+), 2 deletions(-) diff --git a/include/net/netmem.h b/include/net/netmem.h index c61d5b21e7b4..64af9a288c80 100644 --- a/include/net/netmem.h +++ b/include/net/netmem.h @@ -20,8 +20,17 @@ DECLARE_STATIC_KEY_FALSE(page_pool_mem_providers); */ #define NET_IOV 0x01UL +enum net_iov_type { + NET_IOV_DMABUF, + NET_IOV_IOURING, + + /* Force size to unsigned long to make the NET_IOV_ASSERTS below pass. + */ + NET_IOV_MAX = ULONG_MAX, +}; + struct net_iov { - unsigned long __unused_padding; + enum net_iov_type type; unsigned long pp_magic; struct page_pool *pp; struct net_iov_area *owner; diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c index 0f46e0404c04..17a54e74ed5d 100644 --- a/io_uring/zcrx.c +++ b/io_uring/zcrx.c @@ -247,6 +247,7 @@ static int io_zcrx_create_area(struct io_zcrx_ifq *ifq, niov->owner = &area->nia; area->freelist[i] = i; atomic_set(&area->user_refs[i], 0); + niov->type = NET_IOV_IOURING; } area->free_count = nr_iovs; diff --git a/net/core/devmem.c b/net/core/devmem.c index 6e27a47d0493..f5c3a7e6dbb7 100644 --- a/net/core/devmem.c +++ b/net/core/devmem.c @@ -30,7 +30,7 @@ static const struct memory_provider_ops dmabuf_devmem_ops; bool net_is_devmem_iov(struct net_iov *niov) { - return niov->pp->mp_ops == &dmabuf_devmem_ops; + return niov->type == NET_IOV_DMABUF; } static void net_devmem_dmabuf_free_chunk_owner(struct gen_pool *genpool, @@ -266,6 +266,7 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, for (i = 0; i < owner->area.num_niovs; i++) { niov = &owner->area.niovs[i]; + niov->type = NET_IOV_DMABUF; niov->owner = &owner->area; page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov), net_devmem_get_dma_addr(niov)); base-commit: bbfc077d457272bcea4f14b3a28247ade99b196d -- 2.49.0.777.g153de2bbd5-goog

5 months

2
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[PATCH v5 RESEND iproute2-next 0/1] DUALPI2 iproute2 patch

by chia-yu.chang＠nokia-bell-labs.com

From: Chia-Yu Chang <chia-yu.chang(a)nokia-bell-labs.com> Hello, Please find DUALPI2 iproute2 patch v4. v5 (25-Mar-25) - Use matches() to replace current strcmp() (Stephen Hemminger <stephen(a)networkplumber.org>) - Use general parse_percent() for handling scaled percentage values (Stephen Hemminger <stephen(a)networkplumber.org>) - Add print function for JSON of dualpi2 stats (Stephen Hemminger <stephen(a)networkplumber.org>) v4 (16-Mar-25) - Add min_qlen_step to dualpi2 attribute as the minimum queue length in number of packets in the L-queue to start step amrking. v3 (21-Feb-25) - Add memlimit to dualpi2 attribute, and add memory_used, max_memory_used, memory_limit in dualpi2 stats (Dave Taht <dave.taht(a)gmail.com>) - Update manual to align latest implementation and clarify the queue naming and default unit - Use common "get_scaled_alpha_beta" and clean print_opt for Dualpi2 v2 (23-Oct-24) - Rename get_float in dualpi2 to get_float_min_max in utils.c - Move get_float from iplink_can.c in utils.c (Stephen Hemminger <stephen(a)networkplumber.org>) - Add print function for JSON of dualpi2 (Stephen Hemminger <stephen(a)networkplumber.org>) For more details of DualPI2, plesae refer IETF RFC9332 (https://datatracker.ietf.org/doc/html/rfc9332). Best Regards, Chia-Yu Chia-Yu Chang (1): tc: add dualpi2 scheduler module bash-completion/tc | 11 +- include/uapi/linux/pkt_sched.h | 39 +++ include/utils.h | 2 + ip/iplink_can.c | 14 - lib/utils.c | 30 ++ man/man8/tc-dualpi2.8 | 249 ++++++++++++++++ tc/Makefile | 1 + tc/q_dualpi2.c | 519 +++++++++++++++++++++++++++++++++ 8 files changed, 850 insertions(+), 15 deletions(-) create mode 100644 man/man8/tc-dualpi2.8 create mode 100644 tc/q_dualpi2.c -- 2.34.1

5 months

3
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[PATCH v3 net-next 00/15] AccECN protocol patch series

by chia-yu.chang＠nokia-bell-labs.com

From: Chia-Yu Chang <chia-yu.chang(a)nokia-bell-labs.com> Hello, Plese find the v3: v3(14-Apr-2025) - Fix patch apply issue in v2 (Jakub Kicinski <kuba(a)kernel.org>) v2 (18-Mar-2025) - Add one missing patch from previous AccECN protocol preparation patch series to this patch series The full patch series can be found in https://github.com/L4STeam/linux-net-next/commits/upstream_l4steam/ The Accurate ECN draft can be found in https://datatracker.ietf.org/doc/html/draft-ietf-tcpm-accurate-ecn-28 Best regards, Chia-Yu Chia-Yu Chang (1): tcp: accecn: AccECN option failure handling Ilpo Järvinen (14): tcp: reorganize SYN ECN code tcp: fast path functions later tcp: AccECN core tcp: accecn: AccECN negotiation tcp: accecn: add AccECN rx byte counters tcp: accecn: AccECN needs to know delivered bytes tcp: allow embedding leftover into option padding tcp: sack option handling improvements tcp: accecn: AccECN option tcp: accecn: AccECN option send control tcp: accecn: AccECN option ceb/cep heuristic tcp: accecn: AccECN ACE field multi-wrap heuristic tcp: accecn: try to fit AccECN option with SACK tcp: try to avoid safer when ACKs are thinned include/linux/tcp.h | 27 +- include/net/netns/ipv4.h | 2 + include/net/tcp.h | 198 +++++++++++-- include/uapi/linux/tcp.h | 7 + net/ipv4/syncookies.c | 3 + net/ipv4/sysctl_net_ipv4.c | 19 ++ net/ipv4/tcp.c | 26 +- net/ipv4/tcp_input.c | 591 +++++++++++++++++++++++++++++++++++-- net/ipv4/tcp_ipv4.c | 5 +- net/ipv4/tcp_minisocks.c | 92 +++++- net/ipv4/tcp_output.c | 302 +++++++++++++++++-- net/ipv6/syncookies.c | 1 + net/ipv6/tcp_ipv6.c | 1 + 13 files changed, 1178 insertions(+), 96 deletions(-) -- 2.34.1

5 months

3
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[PATCH v3 net-next 00/15] AccECN protocol patch series

by chia-yu.chang＠nokia-bell-labs.com

From: Chia-Yu Chang <chia-yu.chang(a)nokia-bell-labs.com> Hello, Plese find the v3: v3(14-Apr-2025) - Fix patch apply issue in v2 (Jakub Kicinski <kuba(a)kernel.org>) v2 (18-Mar-2025) - Add one missing patch from previous AccECN protocol preparation patch series to this patch series The full patch series can be found in https://github.com/L4STeam/linux-net-next/commits/upstream_l4steam/ The Accurate ECN draft can be found in https://datatracker.ietf.org/doc/html/draft-ietf-tcpm-accurate-ecn-28 Best regards, Chia-Yu Chia-Yu Chang (1): tcp: accecn: AccECN option failure handling Ilpo Järvinen (14): tcp: reorganize SYN ECN code tcp: fast path functions later tcp: AccECN core tcp: accecn: AccECN negotiation tcp: accecn: add AccECN rx byte counters tcp: accecn: AccECN needs to know delivered bytes tcp: allow embedding leftover into option padding tcp: sack option handling improvements tcp: accecn: AccECN option tcp: accecn: AccECN option send control tcp: accecn: AccECN option ceb/cep heuristic tcp: accecn: AccECN ACE field multi-wrap heuristic tcp: accecn: try to fit AccECN option with SACK tcp: try to avoid safer when ACKs are thinned include/linux/tcp.h | 27 +- include/net/netns/ipv4.h | 2 + include/net/tcp.h | 198 +++++++++++-- include/uapi/linux/tcp.h | 7 + net/ipv4/syncookies.c | 3 + net/ipv4/sysctl_net_ipv4.c | 19 ++ net/ipv4/tcp.c | 26 +- net/ipv4/tcp_input.c | 591 +++++++++++++++++++++++++++++++++++-- net/ipv4/tcp_ipv4.c | 5 +- net/ipv4/tcp_minisocks.c | 92 +++++- net/ipv4/tcp_output.c | 302 +++++++++++++++++-- net/ipv6/syncookies.c | 1 + net/ipv6/tcp_ipv6.c | 1 + 13 files changed, 1178 insertions(+), 96 deletions(-) -- 2.34.1

5 months

1
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[PATCH] kunit: qemu_configs: Disable faulting tests on 32-bit SPARC

by David Gow

The 32-bit sparc configuration (--arch sparc) crashes on the kunit_fault_test. It's known that some architectures don't handle deliberate segfaults in kernel mode well, so there's a config switch to disable tests which rely upon it by default. Use this for the sparc config, making sure the default config for it passes. Fixes: 87c9c1631788 ("kunit: tool: add support for QEMU") Signed-off-by: David Gow <davidgow(a)google.com> --- Another quick fix to the sparc qemu_config I noticed while testing [1]. --- tools/testing/kunit/qemu_configs/sparc.py | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/testing/kunit/qemu_configs/sparc.py b/tools/testing/kunit/qemu_configs/sparc.py index 3131dd299a6e..2019550a1b69 100644 --- a/tools/testing/kunit/qemu_configs/sparc.py +++ b/tools/testing/kunit/qemu_configs/sparc.py @@ -2,6 +2,7 @@ from ..qemu_config import QemuArchParams QEMU_ARCH = QemuArchParams(linux_arch='sparc', kconfig=''' +CONFIG_KUNIT_FAULT_TEST=n CONFIG_SPARC32=y CONFIG_SERIAL_SUNZILOG=y CONFIG_SERIAL_SUNZILOG_CONSOLE=y -- 2.49.0.604.gff1f9ca942-goog

5 months

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[PATCH 0/2] kunit: qemu_configs: Add 64-bit SPARC configuration

by Thomas Weißschuh

Add a basic config to run kunit tests on 64-bit SPARC. Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de> --- Thomas Weißschuh (2): kunit: qemu_configs: sparc: Explicitly enable CONFIG_SPARC32=y kunit: qemu_configs: Add 64-bit SPARC configuration tools/testing/kunit/qemu_configs/sparc.py | 1 + tools/testing/kunit/qemu_configs/sparc64.py | 16 ++++++++++++++++ 2 files changed, 17 insertions(+) --- base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8 change-id: 20250214-kunit-qemu-sparc64-e9ad2883b8e2 Best regards, -- Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>

5 months

2
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[PATCH RFT v16 0/8] 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, 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 pointer, this must point to memory mapped for use as a shadow stackby map_shadow_stack() with an architecture specified 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 available to me. [1] https://lore.kernel.org/linux-arm-kernel/20241001-arm64-gcs-v13-0-222b78d87… Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v16: - Rebase onto v6.15-rc2. - Roll in fixes from x86 testing from Rick Edgecombe. - Rework so that the argument is shadow_stack_token. - Link to v15: https://lore.kernel.org/r/20250408-clone3-shadow-stack-v15-0-3fa245c6e3be@k… Changes in v15: - Rebase onto v6.15-rc1. - Link to v14: https://lore.kernel.org/r/20250206-clone3-shadow-stack-v14-0-805b53af73b9@k… Changes in v14: - Rebase onto v6.14-rc1. - Link to v13: https://lore.kernel.org/r/20241203-clone3-shadow-stack-v13-0-93b89a81a5ed@k… Changes in v13: - Rebase onto v6.13-rc1. - Link to v12: https://lore.kernel.org/r/20241031-clone3-shadow-stack-v12-0-7183eb8bee17@k… Changes in v12: - Add the regular prctl() to the userspace API document since arm64 support is queued in -next. - Link to v11: https://lore.kernel.org/r/20241005-clone3-shadow-stack-v11-0-2a6a2bd6d651@k… Changes in v11: - Rebase onto arm64 for-next/gcs, which is based on v6.12-rc1, and integrate arm64 support. - Rework the interface to specify a shadow stack pointer rather than a base and size like we do for the regular stack. - Link to v10: https://lore.kernel.org/r/20240821-clone3-shadow-stack-v10-0-06e8797b9445@k… Changes in v10: - Integrate fixes & improvements for the x86 implementation from Rick Edgecombe. - Require that the shadow stack be VM_WRITE. - Require that the shadow stack base and size be sizeof(void *) aligned. - Clean up trailing newline. - Link to v9: https://lore.kernel.org/r/20240819-clone3-shadow-stack-v9-0-962d74f99464@ke… Changes in v9: - Pull token validation earlier and report problems with an error return to parent rather than signal delivery to the child. - Verify that the top of the supplied shadow stack is VM_SHADOW_STACK. - Rework token validation to only do the page mapping once. - Drop no longer needed support for testing for signals in selftest. - Fix typo in comments. - Link to v8: https://lore.kernel.org/r/20240808-clone3-shadow-stack-v8-0-0acf37caf14c@ke… Changes in v8: - Fix token verification with user specified shadow stack. - Don't track user managed shadow stacks for child processes. - Link to v7: https://lore.kernel.org/r/20240731-clone3-shadow-stack-v7-0-a9532eebfb1d@ke… Changes in v7: - Rebase onto v6.11-rc1. - Typo fixes. - Link to v6: https://lore.kernel.org/r/20240623-clone3-shadow-stack-v6-0-9ee7783b1fb9@ke… 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 (8): arm64/gcs: Return a success value from gcs_alloc_thread_stack() Documentation: userspace-api: Add shadow stack API documentation selftests: Provide helper header for shadow stack testing 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: 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 | 44 +++++ arch/arm64/include/asm/gcs.h | 8 +- arch/arm64/kernel/process.c | 8 +- arch/arm64/mm/gcs.c | 61 +++++- arch/x86/include/asm/shstk.h | 11 +- arch/x86/kernel/process.c | 2 +- arch/x86/kernel/shstk.c | 57 +++++- include/asm-generic/cacheflush.h | 11 ++ include/linux/sched/task.h | 17 ++ include/uapi/linux/sched.h | 9 +- kernel/fork.c | 96 +++++++-- tools/testing/selftests/clone3/clone3.c | 226 ++++++++++++++++++---- tools/testing/selftests/clone3/clone3_selftests.h | 65 ++++++- tools/testing/selftests/ksft_shstk.h | 98 ++++++++++ 15 files changed, 633 insertions(+), 81 deletions(-) --- base-commit: 8ffd015db85fea3e15a77027fda6c02ced4d2444 change-id: 20231019-clone3-shadow-stack-15d40d2bf536 Best regards, -- Mark Brown <broonie(a)kernel.org>

5 months

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[PATCH v8 0/6] rust: reduce `as` casts, enable related lints

by Tamir Duberstein

This started with a patch that enabled `clippy::ptr_as_ptr`. Benno Lossin suggested I also look into `clippy::ptr_cast_constness` and I discovered `clippy::as_ptr_cast_mut`. This series now enables all 3 lints. It also enables `clippy::as_underscore` which ensures other pointer casts weren't missed. The first commit reduces the need for pointer casts and is shared with another series[1]. As a later addition, `clippy::cast_lossless` and `clippy::ref_as_ptr` are also enabled. Link: https://lore.kernel.org/all/20250307-no-offset-v1-0-0c728f63b69c@gmail.com/ [1] Signed-off-by: Tamir Duberstein <tamird(a)gmail.com> --- Changes in v8: - Use coercion to go ref -> ptr. - rustfmt. - Rebase on v6.15-rc1. - Extract first commit to its own series as it is shared with other series. - Link to v7: https://lore.kernel.org/r/20250325-ptr-as-ptr-v7-0-87ab452147b9@gmail.com Changes in v7: - Add patch to enable `clippy::ref_as_ptr`. - Link to v6: https://lore.kernel.org/r/20250324-ptr-as-ptr-v6-0-49d1b7fd4290@gmail.com Changes in v6: - Drop strict provenance patch. - Fix URLs in doc comments. - Add patch to enable `clippy::cast_lossless`. - Rebase on rust-next. - Link to v5: https://lore.kernel.org/r/20250317-ptr-as-ptr-v5-0-5b5f21fa230a@gmail.com Changes in v5: - Use `pointer::addr` in OF. (Boqun Feng) - Add documentation on stubs. (Benno Lossin) - Mark stubs `#[inline]`. - Pick up Alice's RB on a shared commit from https://lore.kernel.org/all/Z9f-3Aj3_FWBZRrm@google.com/. - Link to v4: https://lore.kernel.org/r/20250315-ptr-as-ptr-v4-0-b2d72c14dc26@gmail.com Changes in v4: - Add missing SoB. (Benno Lossin) - Use `without_provenance_mut` in alloc. (Boqun Feng) - Limit strict provenance lints to the `kernel` crate to avoid complex logic in the build system. This can be revisited on MSRV >= 1.84.0. - Rebase on rust-next. - Link to v3: https://lore.kernel.org/r/20250314-ptr-as-ptr-v3-0-e7ba61048f4a@gmail.com Changes in v3: - Fixed clippy warning in rust/kernel/firmware.rs. (kernel test robot) Link: https://lore.kernel.org/all/202503120332.YTCpFEvv-lkp@intel.com/ - s/as u64/as bindings::phys_addr_t/g. (Benno Lossin) - Use strict provenance APIs and enable lints. (Benno Lossin) - Link to v2: https://lore.kernel.org/r/20250309-ptr-as-ptr-v2-0-25d60ad922b7@gmail.com Changes in v2: - Fixed typo in first commit message. - Added additional patches, converted to series. - Link to v1: https://lore.kernel.org/r/20250307-ptr-as-ptr-v1-1-582d06514c98@gmail.com --- Tamir Duberstein (6): rust: enable `clippy::ptr_as_ptr` lint rust: enable `clippy::ptr_cast_constness` lint rust: enable `clippy::as_ptr_cast_mut` lint rust: enable `clippy::as_underscore` lint rust: enable `clippy::cast_lossless` lint rust: enable `clippy::ref_as_ptr` lint Makefile | 6 ++++++ drivers/gpu/drm/drm_panic_qr.rs | 2 +- rust/bindings/lib.rs | 3 +++ rust/kernel/alloc/allocator_test.rs | 2 +- rust/kernel/alloc/kvec.rs | 4 ++-- rust/kernel/block/mq/operations.rs | 2 +- rust/kernel/block/mq/request.rs | 7 ++++--- rust/kernel/device.rs | 5 +++-- rust/kernel/device_id.rs | 5 +++-- rust/kernel/devres.rs | 19 ++++++++++--------- rust/kernel/dma.rs | 6 +++--- rust/kernel/error.rs | 2 +- rust/kernel/firmware.rs | 3 ++- rust/kernel/fs/file.rs | 3 ++- rust/kernel/io.rs | 18 +++++++++--------- rust/kernel/kunit.rs | 15 +++++++-------- rust/kernel/list/impl_list_item_mod.rs | 2 +- rust/kernel/miscdevice.rs | 2 +- rust/kernel/net/phy.rs | 4 ++-- rust/kernel/of.rs | 6 +++--- rust/kernel/pci.rs | 11 +++++++---- rust/kernel/platform.rs | 4 +++- rust/kernel/print.rs | 11 +++++------ rust/kernel/seq_file.rs | 3 ++- rust/kernel/str.rs | 16 +++++++++------- rust/kernel/sync/poll.rs | 2 +- rust/kernel/time/hrtimer/pin.rs | 2 +- rust/kernel/time/hrtimer/pin_mut.rs | 2 +- rust/kernel/uaccess.rs | 10 ++++------ rust/kernel/workqueue.rs | 12 ++++++------ rust/uapi/lib.rs | 3 +++ 31 files changed, 107 insertions(+), 85 deletions(-) --- base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8 change-id: 20250307-ptr-as-ptr-21b1867fc4d4 prerequisite-change-id: 20250409-container-of-mutness-b153dab4388d:v1 prerequisite-patch-id: 53d5889db599267f87642bb0ae3063c29bc24863 Best regards, -- Tamir Duberstein <tamird(a)gmail.com>

5 months

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Linux-kselftest-mirror April 2025