- Linux-kselftest-mirror - lists.linaro.org

[PATCH] selftest: net: fix variable sized type not at the end of struct warnings

by Ankit Khushwaha

Some network selftests defined variable-sized types defined at the end of struct causing -Wgnu-variable-sized-type-not-at-end warning. warning: timestamping.c:285:18: warning: field 'cm' with variable sized type 'struct cmsghdr' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] 285 | struct cmsghdr cm; | ^ ipsec.c:835:5: warning: field 'u' with variable sized type 'union (unnamed union at ipsec.c:831:3)' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] 835 | } u; | ^ This patch move these field at the end of struct to fix these warnings. Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux(a)gmail.com> --- tools/testing/selftests/net/ipsec.c | 2 +- tools/testing/selftests/net/timestamping.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/net/ipsec.c b/tools/testing/selftests/net/ipsec.c index 0ccf484b1d9d..36083c8f884f 100644 --- a/tools/testing/selftests/net/ipsec.c +++ b/tools/testing/selftests/net/ipsec.c @@ -828,12 +828,12 @@ static int xfrm_state_pack_algo(struct nlmsghdr *nh, size_t req_sz, struct xfrm_desc *desc) { struct { + char buf[XFRM_ALGO_KEY_BUF_SIZE]; union { struct xfrm_algo alg; struct xfrm_algo_aead aead; struct xfrm_algo_auth auth; } u; - char buf[XFRM_ALGO_KEY_BUF_SIZE]; } alg = {}; size_t alen, elen, clen, aelen; unsigned short type; diff --git a/tools/testing/selftests/net/timestamping.c b/tools/testing/selftests/net/timestamping.c index 044bc0e9ed81..ad2be2143698 100644 --- a/tools/testing/selftests/net/timestamping.c +++ b/tools/testing/selftests/net/timestamping.c @@ -282,8 +282,8 @@ static void recvpacket(int sock, int recvmsg_flags, struct iovec entry; struct sockaddr_in from_addr; struct { - struct cmsghdr cm; char control[512]; + struct cmsghdr cm; } control; int res; -- 2.51.0

2 weeks, 3 days

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[PATCH v5 00/34] sparc64: vdso: Switch to the generic vDSO library

by Thomas Weißschuh

The generic vDSO provides a lot common functionality shared between different architectures. SPARC is the last architecture not using it, preventing some necessary code cleanup. Make use of the generic infrastructure. Follow-up to and replacement for Arnd's SPARC vDSO removal patches: https://lore.kernel.org/lkml/20250707144726.4008707-1-arnd@kernel.org/ SPARC64 can not map .bss into userspace, so the vDSO datapages are switched over to be allocated dynamically. This requires changes to the s390 and random subsystem vDSO initialization as preparation. The random subsystem changes in turn require some cleanup of the vDSO headers to not end up as ugly #ifdef mess. Tested on a Niagara T4 and QEMU. This has a semantic conflict with my series "vdso: Reject absolute relocations during build" [0]. The last patch of this series expects all users of the generic vDSO library to use the vdsocheck tool. This is not the case (yet) for SPARC64. I do have the patches for the integration, the specifics will depend on which series is applied first. Based on v6.18-rc1. [0] https://lore.kernel.org/lkml/20250812-vdso-absolute-reloc-v4-0-61a8b615e5ec… Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de> --- Changes in v5: - Merge the patches for 'struct page' mapping and dynamic allocation - Zero out newly-allocated data pages - Pick up review tags - Link to v4: https://lore.kernel.org/r/20251014-vdso-sparc64-generic-2-v4-0-e0607bf49dea… Changes in v4: - Rebase on v6.18-rc1. - Keep inclusion of asm/clocksource.h from linux/clocksource.h - Reword description of "s390/time: Set up vDSO datapage later" - Link to v3: https://lore.kernel.org/r/20250917-vdso-sparc64-generic-2-v3-0-3679b1bc8ee8… Changes in v3: - Allocate vDSO data pages dynamically (and lots of preparations for that) - Drop clock_getres() - Fix 32bit clock_gettime() syscall fallback - Link to v2: https://lore.kernel.org/r/20250815-vdso-sparc64-generic-2-v2-0-b5ff80672347… Changes in v2: - Rebase on v6.17-rc1 - Drop RFC state - Fix typo in commit message - Drop duplicate 'select GENERIC_TIME_VSYSCALL' - Merge "sparc64: time: Remove architecture-specific clocksource data" into the main conversion patch. It violated the check in __clocksource_register_scale() - Link to v1: https://lore.kernel.org/r/20250724-vdso-sparc64-generic-2-v1-0-e376a3bd24d1… --- Arnd Bergmann (1): clocksource: remove ARCH_CLOCKSOURCE_DATA Thomas Weißschuh (33): selftests: vDSO: vdso_test_correctness: Handle different tv_usec types arm64: vDSO: getrandom: Explicitly include asm/alternative.h arm64: vDSO: gettimeofday: Explicitly include vdso/clocksource.h arm64: vDSO: compat_gettimeofday: Add explicit includes ARM: vdso: gettimeofday: Add explicit includes powerpc/vdso/gettimeofday: Explicitly include vdso/time32.h powerpc/vdso: Explicitly include asm/cputable.h and asm/feature-fixups.h LoongArch: vDSO: Explicitly include asm/vdso/vdso.h MIPS: vdso: Add include guard to asm/vdso/vdso.h MIPS: vdso: Explicitly include asm/vdso/vdso.h random: vDSO: Add explicit includes vdso/gettimeofday: Add explicit includes vdso/helpers: Explicitly include vdso/processor.h vdso/datapage: Remove inclusion of gettimeofday.h vdso/datapage: Trim down unnecessary includes random: vDSO: trim vDSO includes random: vDSO: remove ifdeffery random: vDSO: split out datapage update into helper functions random: vDSO: only access vDSO datapage after random_init() s390/time: Set up vDSO datapage later vdso/datastore: Reduce scope of some variables in vvar_fault() vdso/datastore: Drop inclusion of linux/mmap_lock.h vdso/datastore: Allocate data pages dynamically sparc64: vdso: Link with -z noexecstack sparc64: vdso: Remove obsolete "fake section table" reservation sparc64: vdso: Replace code patching with runtime conditional sparc64: vdso: Move hardware counter read into header sparc64: vdso: Move syscall fallbacks into header sparc64: vdso: Introduce vdso/processor.h sparc64: vdso: Switch to the generic vDSO library sparc64: vdso2c: Drop sym_vvar_start handling sparc64: vdso2c: Remove symbol handling sparc64: vdso: Implement clock_gettime64() arch/arm/include/asm/vdso/gettimeofday.h | 2 + arch/arm64/include/asm/vdso/compat_gettimeofday.h | 3 + arch/arm64/include/asm/vdso/gettimeofday.h | 2 + arch/arm64/kernel/vdso/vgetrandom.c | 2 + arch/loongarch/kernel/process.c | 1 + arch/loongarch/kernel/vdso.c | 1 + arch/mips/include/asm/vdso/vdso.h | 5 + arch/mips/kernel/vdso.c | 1 + arch/powerpc/include/asm/vdso/gettimeofday.h | 1 + arch/powerpc/include/asm/vdso/processor.h | 3 + arch/s390/kernel/time.c | 4 +- arch/sparc/Kconfig | 3 +- arch/sparc/include/asm/clocksource.h | 9 - arch/sparc/include/asm/processor.h | 3 + arch/sparc/include/asm/processor_32.h | 2 - arch/sparc/include/asm/processor_64.h | 25 -- arch/sparc/include/asm/vdso.h | 2 - arch/sparc/include/asm/vdso/clocksource.h | 10 + arch/sparc/include/asm/vdso/gettimeofday.h | 184 ++++++++++ arch/sparc/include/asm/vdso/processor.h | 41 +++ arch/sparc/include/asm/vdso/vsyscall.h | 10 + arch/sparc/include/asm/vvar.h | 75 ---- arch/sparc/kernel/Makefile | 1 - arch/sparc/kernel/time_64.c | 6 +- arch/sparc/kernel/vdso.c | 69 ---- arch/sparc/vdso/Makefile | 8 +- arch/sparc/vdso/vclock_gettime.c | 380 ++------------------- arch/sparc/vdso/vdso-layout.lds.S | 26 +- arch/sparc/vdso/vdso.lds.S | 2 - arch/sparc/vdso/vdso2c.c | 24 -- arch/sparc/vdso/vdso2c.h | 45 +-- arch/sparc/vdso/vdso32/vdso32.lds.S | 4 +- arch/sparc/vdso/vma.c | 274 +-------------- drivers/char/random.c | 71 ++-- include/linux/clocksource.h | 6 +- include/linux/vdso_datastore.h | 6 + include/vdso/datapage.h | 23 +- include/vdso/helpers.h | 1 + init/main.c | 2 + kernel/time/Kconfig | 4 - lib/vdso/datastore.c | 74 ++-- lib/vdso/getrandom.c | 3 + lib/vdso/gettimeofday.c | 17 + .../testing/selftests/vDSO/vdso_test_correctness.c | 8 +- 44 files changed, 449 insertions(+), 994 deletions(-) --- base-commit: 28b1ac5ccd8d4900a8f53f0e6e84d517a7ccc71f change-id: 20250722-vdso-sparc64-generic-2-25f2e058e92c Best regards, -- Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>

2 weeks, 4 days

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[PATCH net v10 0/4] net: netpoll: fix memory leak and add comprehensive selftests

by Breno Leitao

Fix a memory leak in netpoll and introduce netconsole selftests that expose the issue when running with kmemleak detection enabled. This patchset includes a selftest for netpoll with multiple concurrent users (netconsole + bonding), which simulates the scenario from test[1] that originally demonstrated the issue allegedly fixed by commit efa95b01da18 ("netpoll: fix use after free") - a commit that is now being reverted. Sending this to "net" branch because this is a fix, and the selftest might help with the backports validation. Link: https://lore.kernel.org/lkml/96b940137a50e5c387687bb4f57de8b0435a653f.14048… [1] Signed-off-by: Breno Leitao <leitao(a)debian.org> --- Changes in v10: - Get rid of the create_and_enable_dynamic_target() (Simon) - Link to v9: https://lore.kernel.org/r/20251106-netconsole_torture-v9-0-f73cd147c13c@deb… Changes in v9: - Reordered the config entries in tools/testing/selftests/drivers/net/bonding/config (NIPA) - Link to v8: https://lore.kernel.org/r/20251104-netconsole_torture-v8-0-5288440e2fa0@deb… Changes in v8: - Sending it again, now that commit 1a8fed52f7be1 ("netdevsim: set the carrier when the device goes up") has landed in net - Created one namespace for TX and one for RX (Paolo) - Used additional helpers to create and delete netdevsim (Paolo) - Link to v7: https://lore.kernel.org/r/20251003-netconsole_torture-v7-0-aa92fcce62a9@deb… Changes in v7: - Rebased on top of `net` - Link to v6: https://lore.kernel.org/r/20251002-netconsole_torture-v6-0-543bf52f6b46@deb… Changes in v6: - Expand the tests even more and some small fixups - Moved the test to bonding selftests - Link to v5: https://lore.kernel.org/r/20250918-netconsole_torture-v5-0-77e25e0a4eb6@deb… Changes in v5: - Set CONFIG_BONDING=m in selftests/drivers/net/config. - Link to v4: https://lore.kernel.org/r/20250917-netconsole_torture-v4-0-0a5b3b8f81ce@deb… Changes in v4: - Added an additional selftest to test multiple netpoll users in parallel - Link to v3: https://lore.kernel.org/r/20250905-netconsole_torture-v3-0-875c7febd316@deb… Changes in v3: - This patchset is a merge of the fix and the selftest together as recommended by Jakub. Changes in v2: - Reuse the netconsole creation from lib_netcons.sh. Thus, refactoring the create_dynamic_target() (Jakub) - Move the "wait" to after all the messages has been sent. - Link to v1: https://lore.kernel.org/r/20250902-netconsole_torture-v1-1-03c6066598e9@deb… --- Breno Leitao (4): net: netpoll: fix incorrect refcount handling causing incorrect cleanup selftest: netcons: refactor target creation selftest: netcons: create a torture test selftest: netcons: add test for netconsole over bonded interfaces net/core/netpoll.c | 7 +- tools/testing/selftests/drivers/net/Makefile | 1 + .../testing/selftests/drivers/net/bonding/Makefile | 2 + tools/testing/selftests/drivers/net/bonding/config | 4 + .../drivers/net/bonding/netcons_over_bonding.sh | 361 +++++++++++++++++++++ .../selftests/drivers/net/lib/sh/lib_netcons.sh | 78 ++++- .../selftests/drivers/net/netcons_torture.sh | 130 ++++++++ 7 files changed, 566 insertions(+), 17 deletions(-) --- base-commit: 7d1988a943850c584e8e2e4bcc7a3b5275024072 change-id: 20250902-netconsole_torture-8fc23f0aca99 Best regards, -- Breno Leitao <leitao(a)debian.org>

2 weeks, 4 days

2
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[PATCH] selftests/tracing: Run sample events to clear page cache events

by Steven Rostedt

From: Steven Rostedt <rostedt(a)goodmis.org> The tracing selftest "event-filter-function.tc" was failing because it first runs the "sample_events" function that triggers the kmem_cache_free event and it looks at what function was used during a call to "ls". But the first time it calls this, it could trigger events that are used to pull pages into the page cache. The rest of the test uses the function it finds during that call to see if it will be called in subsequent "sample_events" calls. But if there's no need to pull pages into the page cache, it will not trigger that function and the test will fail. Call the "sample_events" twice to trigger all the page cache work before it calls it to find a function to use in subsequent checks. Cc: stable(a)vger.kernel.org Fixes: eb50d0f250e96 ("selftests/ftrace: Choose target function for filter test from samples") Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> --- .../selftests/ftrace/test.d/filter/event-filter-function.tc | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc index c62165fabd0c..003f612f57b0 100644 --- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc +++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc @@ -20,6 +20,10 @@ sample_events() { echo 0 > tracing_on echo 0 > events/enable +# Clear functions caused by page cache; run sample_events twice +sample_events +sample_events + echo "Get the most frequently calling function" echo > trace sample_events -- 2.51.0

2 weeks, 4 days

3
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[PATCH 0/4] vfio: selftests: update DMA mapping tests to use queried IOVA ranges

by Alex Mastro

Not all IOMMUs support the same virtual address width as the processor, for instance older Intel consumer platforms only support 39-bits of IOMMU address space. On such platforms, using the virtual address as the IOVA and mappings at the top of the address space both fail. VFIO and IOMMUFD have facilities for retrieving valid IOVA ranges, VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE and IOMMU_IOAS_IOVA_RANGES, respectively. These provide compatible arrays of ranges from which we can construct a simple allocator and record the maximum supported IOVA address. Use this new allocator in place of reusing the virtual address, and incorporate the maximum supported IOVA into the limit testing. This latter change doesn't test quite the same absolute end-of-address space behavior but still seems to have some value. Testing for overflow is skipped when a reduced address space is supported as the desired errno is not generated. This series is based on Alex Williamson's "Incorporate IOVA range info" [1] along with feedback from the discussion in David Matlack's "Skip vfio_dma_map_limit_test if mapping returns -EINVAL" [2]. Given David's plans to split IOMMU concerns from devices as described in [3], this series' home for `struct iova_allocator` is likely to be short lived, since it resides in vfio_pci_device.c. I assume that the rework can move this functionality to a more appropriate location next to other IOMMU-focused code, once such a place exists. [1] https://lore.kernel.org/all/20251108212954.26477-1-alex@shazbot.org/#t [2] https://lore.kernel.org/all/20251107222058.2009244-1-dmatlack@google.com/ [3] https://lore.kernel.org/all/aRIoKJk0uwLD-yGr@google.com/ Signed-off-by: Alex Mastro <amastro(a)fb.com> --- Alex Mastro (4): vfio: selftests: add iova range query helpers vfio: selftests: fix map limit tests to use last available iova vfio: selftests: add iova allocator vfio: selftests: update vfio_dma_mapping_test to allocate iovas .../testing/selftests/vfio/lib/include/vfio_util.h | 22 +- tools/testing/selftests/vfio/lib/vfio_pci_device.c | 226 ++++++++++++++++++++- .../testing/selftests/vfio/vfio_dma_mapping_test.c | 25 ++- 3 files changed, 268 insertions(+), 5 deletions(-) --- base-commit: 0ed3a30fd996cb0cac872432cf25185fda7e5316 change-id: 20251110-iova-ranges-1c09549fbf63 Best regards, -- Alex Mastro <amastro(a)fb.com>

2 weeks, 4 days

3
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[PATCH] selftest/mm: fix pointer comparison in mremap_test

by Ankit Khushwaha

Pointer arthemitic with 'void * addr' and 'unsigned long long dest_alignment' triggers following warning: mremap_test.c:1035:31: warning: pointer comparison always evaluates to false [-Wtautological-compare] 1035 | if (addr + c.dest_alignment < addr) { | ^ typecasting 'addr' to 'unsigned long long' to fix pointer comparison. Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux(a)gmail.com> --- tools/testing/selftests/mm/mremap_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index a95c0663a011..5ae0400176af 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -1032,7 +1032,7 @@ static long long remap_region(struct config c, unsigned int threshold_mb, /* Don't destroy existing mappings unless expected to overlap */ while (!is_remap_region_valid(addr, c.region_size) && !c.overlapping) { /* Check for unsigned overflow */ - if (addr + c.dest_alignment < addr) { + if ((unsigned long long) addr + c.dest_alignment < (unsigned long long) addr) { ksft_print_msg("Couldn't find a valid region to remap to\n"); ret = -1; goto clean_up_src; -- 2.51.0

2 weeks, 4 days

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[PATCH] mm/selftests: Fix -Wtautological-compare warning in mremap_test.c

by Wake Liu

The compiler warns about a tautological comparison in mremap_test.c: "pointer comparison always evaluates to false [-Wtautological-compare]" This occurs when checking for unsigned overflow: if (addr + c.dest_alignment < addr) Cast 'addr' to 'unsigned long long' to ensure the comparison is performed with a wider type, correctly detecting potential overflow and resolving the warning. Signed-off-by: Wake Liu <wakel(a)google.com> --- tools/testing/selftests/mm/mremap_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index bf2863b102e3..c4933f4cbd48 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -1032,7 +1032,7 @@ static long long remap_region(struct config c, unsigned int threshold_mb, /* Don't destroy existing mappings unless expected to overlap */ while (!is_remap_region_valid(addr, c.region_size) && !c.overlapping) { /* Check for unsigned overflow */ - if (addr + c.dest_alignment < addr) { + if ((unsigned long long)addr + c.dest_alignment < (unsigned long long)addr) { ksft_print_msg("Couldn't find a valid region to remap to\n"); ret = -1; goto clean_up_src; -- 2.51.2.1041.gc1ab5b90ca-goog

2 weeks, 4 days

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[PATCH net v9 0/4] net: netpoll: fix memory leak and add comprehensive selftests

by Breno Leitao

Fix a memory leak in netpoll and introduce netconsole selftests that expose the issue when running with kmemleak detection enabled. This patchset includes a selftest for netpoll with multiple concurrent users (netconsole + bonding), which simulates the scenario from test[1] that originally demonstrated the issue allegedly fixed by commit efa95b01da18 ("netpoll: fix use after free") - a commit that is now being reverted. Sending this to "net" branch because this is a fix, and the selftest might help with the backports validation. Link: https://lore.kernel.org/lkml/96b940137a50e5c387687bb4f57de8b0435a653f.14048… [1] Signed-off-by: Breno Leitao <leitao(a)debian.org> --- Changes in v9: - Reordered the config entries in tools/testing/selftests/drivers/net/bonding/config (NIPA) - Link to v8: https://lore.kernel.org/r/20251104-netconsole_torture-v8-0-5288440e2fa0@deb… Changes in v8: - Sending it again, now that commit 1a8fed52f7be1 ("netdevsim: set the carrier when the device goes up") has landed in net - Created one namespace for TX and one for RX (Paolo) - Used additional helpers to create and delete netdevsim (Paolo) - Link to v7: https://lore.kernel.org/r/20251003-netconsole_torture-v7-0-aa92fcce62a9@deb… Changes in v7: - Rebased on top of `net` - Link to v6: https://lore.kernel.org/r/20251002-netconsole_torture-v6-0-543bf52f6b46@deb… Changes in v6: - Expand the tests even more and some small fixups - Moved the test to bonding selftests - Link to v5: https://lore.kernel.org/r/20250918-netconsole_torture-v5-0-77e25e0a4eb6@deb… Changes in v5: - Set CONFIG_BONDING=m in selftests/drivers/net/config. - Link to v4: https://lore.kernel.org/r/20250917-netconsole_torture-v4-0-0a5b3b8f81ce@deb… Changes in v4: - Added an additional selftest to test multiple netpoll users in parallel - Link to v3: https://lore.kernel.org/r/20250905-netconsole_torture-v3-0-875c7febd316@deb… Changes in v3: - This patchset is a merge of the fix and the selftest together as recommended by Jakub. Changes in v2: - Reuse the netconsole creation from lib_netcons.sh. Thus, refactoring the create_dynamic_target() (Jakub) - Move the "wait" to after all the messages has been sent. - Link to v1: https://lore.kernel.org/r/20250902-netconsole_torture-v1-1-03c6066598e9@deb… --- Breno Leitao (4): net: netpoll: fix incorrect refcount handling causing incorrect cleanup selftest: netcons: refactor target creation selftest: netcons: create a torture test selftest: netcons: add test for netconsole over bonded interfaces net/core/netpoll.c | 7 +- tools/testing/selftests/drivers/net/Makefile | 1 + .../testing/selftests/drivers/net/bonding/Makefile | 2 + tools/testing/selftests/drivers/net/bonding/config | 4 + .../drivers/net/bonding/netcons_over_bonding.sh | 361 +++++++++++++++++++++ .../selftests/drivers/net/lib/sh/lib_netcons.sh | 82 ++++- .../selftests/drivers/net/netcons_torture.sh | 130 ++++++++ 7 files changed, 569 insertions(+), 18 deletions(-) --- base-commit: 7d1988a943850c584e8e2e4bcc7a3b5275024072 change-id: 20250902-netconsole_torture-8fc23f0aca99 Best regards, -- Breno Leitao <leitao(a)debian.org>

2 weeks, 4 days

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[PATCH v7 00/12] Direct Map Removal Support for guest_memfd

by Patrick Roy

From: Patrick Roy <roypat(a)amazon.co.uk> [ based on kvm/next ] Unmapping virtual machine guest memory from the host kernel's direct map is a successful mitigation against Spectre-style transient execution issues: If the kernel page tables do not contain entries pointing to guest memory, then any attempted speculative read through the direct map will necessarily be blocked by the MMU before any observable microarchitectural side-effects happen. This means that Spectre-gadgets and similar cannot be used to target virtual machine memory. Roughly 60% of speculative execution issues fall into this category [1, Table 1]. This patch series extends guest_memfd with the ability to remove its memory from the host kernel's direct map, to be able to attain the above protection for KVM guests running inside guest_memfd. Additionally, a Firecracker branch with support for these VMs can be found on GitHub [2]. For more details, please refer to the v5 cover letter [v5]. No substantial changes in design have taken place since. === Changes Since v6 === - Drop patch for passing struct address_space to ->free_folio(), due to possible races with freeing of the address_space. (Hugh) - Stop using PG_uptodate / gmem preparedness tracking to keep track of direct map state. Instead, use the lowest bit of folio->private. (Mike, David) - Do direct map removal when establishing mapping of gmem folio instead of at allocation time, due to impossibility of handling direct map removal errors in kvm_gmem_populate(). (Patrick) - Do TLB flushes after direct map removal, and provide a module parameter to opt out from them, and a new patch to export flush_tlb_kernel_range() to KVM. (Will) [1]: https://download.vusec.net/papers/quarantine_raid23.pdf [2]: https://github.com/firecracker-microvm/firecracker/tree/feature/secret-hidi… [RFCv1]: https://lore.kernel.org/kvm/20240709132041.3625501-1-roypat@amazon.co.uk/ [RFCv2]: https://lore.kernel.org/kvm/20240910163038.1298452-1-roypat@amazon.co.uk/ [RFCv3]: https://lore.kernel.org/kvm/20241030134912.515725-1-roypat@amazon.co.uk/ [v4]: https://lore.kernel.org/kvm/20250221160728.1584559-1-roypat@amazon.co.uk/ [v5]: https://lore.kernel.org/kvm/20250828093902.2719-1-roypat@amazon.co.uk/ [v6]: https://lore.kernel.org/kvm/20250912091708.17502-1-roypat@amazon.co.uk/ Patrick Roy (12): arch: export set_direct_map_valid_noflush to KVM module x86/tlb: export flush_tlb_kernel_range to KVM module mm: introduce AS_NO_DIRECT_MAP KVM: guest_memfd: Add stub for kvm_arch_gmem_invalidate KVM: guest_memfd: Add flag to remove from direct map KVM: guest_memfd: add module param for disabling TLB flushing KVM: selftests: load elf via bounce buffer KVM: selftests: set KVM_MEM_GUEST_MEMFD in vm_mem_add() if guest_memfd != -1 KVM: selftests: Add guest_memfd based vm_mem_backing_src_types KVM: selftests: cover GUEST_MEMFD_FLAG_NO_DIRECT_MAP in existing selftests KVM: selftests: stuff vm_mem_backing_src_type into vm_shape KVM: selftests: Test guest execution from direct map removed gmem Documentation/virt/kvm/api.rst | 5 ++ arch/arm64/include/asm/kvm_host.h | 12 ++++ arch/arm64/mm/pageattr.c | 1 + arch/loongarch/mm/pageattr.c | 1 + arch/riscv/mm/pageattr.c | 1 + arch/s390/mm/pageattr.c | 1 + arch/x86/include/asm/tlbflush.h | 3 +- arch/x86/mm/pat/set_memory.c | 1 + arch/x86/mm/tlb.c | 1 + include/linux/kvm_host.h | 9 +++ include/linux/pagemap.h | 16 +++++ include/linux/secretmem.h | 18 ----- include/uapi/linux/kvm.h | 2 + lib/buildid.c | 4 +- mm/gup.c | 19 ++---- mm/mlock.c | 2 +- mm/secretmem.c | 8 +-- .../testing/selftests/kvm/guest_memfd_test.c | 2 + .../testing/selftests/kvm/include/kvm_util.h | 37 ++++++++--- .../testing/selftests/kvm/include/test_util.h | 8 +++ tools/testing/selftests/kvm/lib/elf.c | 8 +-- tools/testing/selftests/kvm/lib/io.c | 23 +++++++ tools/testing/selftests/kvm/lib/kvm_util.c | 61 +++++++++-------- tools/testing/selftests/kvm/lib/test_util.c | 8 +++ tools/testing/selftests/kvm/lib/x86/sev.c | 1 + .../selftests/kvm/pre_fault_memory_test.c | 1 + .../selftests/kvm/set_memory_region_test.c | 50 ++++++++++++-- .../kvm/x86/private_mem_conversions_test.c | 7 +- virt/kvm/guest_memfd.c | 66 +++++++++++++++++-- virt/kvm/kvm_main.c | 8 +++ 30 files changed, 290 insertions(+), 94 deletions(-) base-commit: a6ad54137af92535cfe32e19e5f3bc1bb7dbd383 -- 2.51.0

2 weeks, 4 days

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[PATCH v2] selftest/mm: fix pointer comparison in mremap_test

by Ankit Khushwaha

Pointer arthemitic with 'void * addr' and 'ulong dest_alignment' triggers following warning: mremap_test.c:1035:31: warning: pointer comparison always evaluates to false [-Wtautological-compare] 1035 | if (addr + c.dest_alignment < addr) { | ^ this warning is raised from clang version 20.1.8 (Fedora 20.1.8-4.fc42). use 'void *tmp_addr' to do the pointer arthemitic. Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux(a)gmail.com> --- Changelog: v2: - use 'void *tmp_addr' for pointer arthemitic instead of typecasting 'addr' to 'unsigned long long' as suggested by Andrew. v1: https://lore.kernel.org/linux-kselftest/20251106104917.39890-1-ankitkhushwa… --- tools/testing/selftests/mm/mremap_test.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index a95c0663a011..308576437228 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -994,7 +994,7 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, unsigned long page_siz static long long remap_region(struct config c, unsigned int threshold_mb, char *rand_addr) { - void *addr, *src_addr, *dest_addr, *dest_preamble_addr = NULL; + void *addr, *tmp_addr, *src_addr, *dest_addr, *dest_preamble_addr = NULL; unsigned long long t, d; struct timespec t_start = {0, 0}, t_end = {0, 0}; long long start_ns, end_ns, align_mask, ret, offset; @@ -1032,7 +1032,8 @@ static long long remap_region(struct config c, unsigned int threshold_mb, /* Don't destroy existing mappings unless expected to overlap */ while (!is_remap_region_valid(addr, c.region_size) && !c.overlapping) { /* Check for unsigned overflow */ - if (addr + c.dest_alignment < addr) { + tmp_addr = addr + c.dest_alignment; + if (tmp_addr < addr) { ksft_print_msg("Couldn't find a valid region to remap to\n"); ret = -1; goto clean_up_src; -- 2.51.1

2 weeks, 5 days

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