September 2024 - Linux-kselftest-mirror

[PATCH HID 0/7] HID: bpf: add a new hook to control hid-generic

by Benjamin Tissoires

This is a slight change from the fundamentals of HID-BPF. In theory, HID-BPF is abstract to the kernel itself, and makes only changes at the HID level (through report descriptors or events emitted to/from the device). However, we have seen a few use cases where HID-BPF might interact with the running kernel when the target device is already handled by a specific device. For example, the XP-Pen/Huion/UC-Logic tablets are handled by hid-uclogic but this driver is also doing a report descriptor fixup without checking if the device has already been fixed by HID-BPF. In the same way, another recent example[0] was when a cheap foot pedal is used and tricks iPhones and Windows machines by presenting itself as a known Apple wireless keyboard. The problem is that this fake keyboard is not presenting a compatible report descriptor and hid-core merges all device nodes together making libinput ignore the keyboard part for historical reasons. Last, there has been a long standing request to allow to disable the input part of a given gamepad while SDL or Steam opens the device through hidraw. This series aims at tackling both of these problems: - first we had a new hook `hid_bpf_driver_probe` which allows the BPF program to decide if the curently probed driver should be used or not - then this same hook can also change the ->driver_data of the struct hid_device_id argument, and we teach hid-generic to use that field as the connect mask. Basically, it means that when we insert a BPF program to fix a device, we can force hid-generic to handle the device, and thus preventing any other kernel driver to tamper with our device. We can also selectively decide to export the hidraw or input nodes when using hid-generic. In the SDL/Steam use case, this would means that the gaming application will load one BPF program per input device it wants to open through hidraw, that BPF program reassigns the input device to hid-generic and disables hid-input, then it can open the new hidraw node. Once that program terminates, the BPF program is removed (either automatically because no-one has the fd of the links open, or manually by SDL/Steam), and the normal driver rebinds to the HID device, restoring full input functionality. This branch is on top of the for-6.12/hidraw branch of hid.git, mainly because that branch saw some selftests/hid changes. [0] https://gitlab.freedesktop.org/libinput/libinput/-/issues/1014 Signed-off-by: Benjamin Tissoires <bentiss(a)kernel.org> --- Benjamin Tissoires (7): selftests/hid: add dependency on hid_common.h selftests/hid: cleanup C tests by adding a common struct uhid_device selftests/hid: allow to parametrize bus/vid/pid/rdesc on the test device HID: bpf: allow BPF programs to force using hid-generic selftests/hid: add test for assigning a given device to hid-generic HID: bpf: Allow to control the connect mask of hid-generic from BPF selftests/hid: add test to disable hid-input Documentation/hid/hid-bpf.rst | 2 +- drivers/hid/bpf/hid_bpf_dispatch.c | 31 ++++ drivers/hid/bpf/hid_bpf_struct_ops.c | 4 + drivers/hid/hid-core.c | 18 +- drivers/hid/hid-generic.c | 5 +- include/linux/hid_bpf.h | 40 ++++ tools/testing/selftests/hid/Makefile | 2 +- tools/testing/selftests/hid/hid_bpf.c | 205 ++++++++++++++++----- tools/testing/selftests/hid/hid_common.h | 112 +++++++---- tools/testing/selftests/hid/hidraw.c | 36 +--- tools/testing/selftests/hid/progs/hid.c | 31 ++++ .../testing/selftests/hid/progs/hid_bpf_helpers.h | 4 + 12 files changed, 372 insertions(+), 118 deletions(-) --- base-commit: 321f7798cfb8d834ae0ed0d467c8bf46804243f9 change-id: 20240829-hid-bpf-hid-generic-61579f5b5945 Best regards, -- Benjamin Tissoires <bentiss(a)kernel.org>

11 months, 3 weeks

2
12
0 0

kselftest/next kselftest-lkdtm: 1 runs, 1 regressions (v6.11-rc1-17-gb4bcdff7e839)

by kernelci.org bot

kselftest/next kselftest-lkdtm: 1 runs, 1 regressions (v6.11-rc1-17-gb4bcdff7e839) Regressions Summary ------------------- platform | arch | lab | compiler | defconfig | regressions ----------------------------+------+-------------+----------+------------------------------+------------ stm32mp157a-dhcor-avenger96 | arm | lab-broonie | gcc-12 | multi_v7_defconfig+kselftest | 1 Details: https://kernelci.org/test/job/kselftest/branch/next/kernel/v6.11-rc1-17-gb4… Test: kselftest-lkdtm Tree: kselftest Branch: next Describe: v6.11-rc1-17-gb4bcdff7e839 URL: https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git SHA: b4bcdff7e839237d89a2aa15b6042b96b0240ac4 Test Regressions ---------------- platform | arch | lab | compiler | defconfig | regressions ----------------------------+------+-------------+----------+------------------------------+------------ stm32mp157a-dhcor-avenger96 | arm | lab-broonie | gcc-12 | multi_v7_defconfig+kselftest | 1 Details: https://kernelci.org/test/plan/id/66d7b2a624bc264505c8685f Results: 0 PASS, 1 FAIL, 0 SKIP Full config: multi_v7_defconfig+kselftest Compiler: gcc-12 (arm-linux-gnueabihf-gcc (Debian 12.2.0-14) 12.2.0) Plain log: https://storage.kernelci.org//kselftest/next/v6.11-rc1-17-gb4bcdff7e839/arm… HTML log: https://storage.kernelci.org//kselftest/next/v6.11-rc1-17-gb4bcdff7e839/arm… Rootfs: http://storage.kernelci.org/images/rootfs/debian/bookworm-kselftest/2024031… * kselftest-lkdtm.login: https://kernelci.org/test/case/id/66d7b2a624bc264505c86860 failing since 35 days (last pass: v6.10-rc7-29-gdf09b0bb09ea, first fail: v6.11-rc1)

11 months, 3 weeks

1
0
0 0

kselftest/next kselftest-seccomp: 2 runs, 1 regressions (v6.11-rc1-17-gb4bcdff7e839)

by kernelci.org bot

kselftest/next kselftest-seccomp: 2 runs, 1 regressions (v6.11-rc1-17-gb4bcdff7e839) Regressions Summary ------------------- platform | arch | lab | compiler | defconfig | regressions ----------------------------+------+-------------+----------+------------------------------+------------ stm32mp157a-dhcor-avenger96 | arm | lab-broonie | gcc-12 | multi_v7_defconfig+kselftest | 1 Details: https://kernelci.org/test/job/kselftest/branch/next/kernel/v6.11-rc1-17-gb4… Test: kselftest-seccomp Tree: kselftest Branch: next Describe: v6.11-rc1-17-gb4bcdff7e839 URL: https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git SHA: b4bcdff7e839237d89a2aa15b6042b96b0240ac4 Test Regressions ---------------- platform | arch | lab | compiler | defconfig | regressions ----------------------------+------+-------------+----------+------------------------------+------------ stm32mp157a-dhcor-avenger96 | arm | lab-broonie | gcc-12 | multi_v7_defconfig+kselftest | 1 Details: https://kernelci.org/test/plan/id/66d7b13e6922285319c8685f Results: 0 PASS, 1 FAIL, 0 SKIP Full config: multi_v7_defconfig+kselftest Compiler: gcc-12 (arm-linux-gnueabihf-gcc (Debian 12.2.0-14) 12.2.0) Plain log: https://storage.kernelci.org//kselftest/next/v6.11-rc1-17-gb4bcdff7e839/arm… HTML log: https://storage.kernelci.org//kselftest/next/v6.11-rc1-17-gb4bcdff7e839/arm… Rootfs: http://storage.kernelci.org/images/rootfs/debian/bookworm-kselftest/2024031… * kselftest-seccomp.login: https://kernelci.org/test/case/id/66d7b13e6922285319c86860 failing since 35 days (last pass: v6.10-rc7-29-gdf09b0bb09ea, first fail: v6.11-rc1)

11 months, 3 weeks

1
0
0 0

kselftest/next build: 7 builds: 2 failed, 5 passed, 1 warning (v6.11-rc1-17-gb4bcdff7e839)

by kernelci.org bot

kselftest/next build: 7 builds: 2 failed, 5 passed, 1 warning (v6.11-rc1-17-gb4bcdff7e839) Full Build Summary: https://kernelci.org/build/kselftest/branch/next/kernel/v6.11-rc1-17-gb4bcd… Tree: kselftest Branch: next Git Describe: v6.11-rc1-17-gb4bcdff7e839 Git Commit: b4bcdff7e839237d89a2aa15b6042b96b0240ac4 Git URL: https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git Built: 4 unique architectures Build Failures Detected: arm64: defconfig+kselftest+arm64-chromebook: (clang-16) FAIL defconfig+kselftest+arm64-chromebook: (gcc-12) FAIL Warnings Detected: arm64: arm: i386: x86_64: x86_64_defconfig+kselftest (clang-16): 1 warning Warnings summary: 1 vmlinux.o: warning: objtool: set_ftrace_ops_ro+0x39: relocation to !ENDBR: .text+0x14ef94 ================================================================================ Detailed per-defconfig build reports: -------------------------------------------------------------------------------- defconfig+kselftest (arm64, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- defconfig+kselftest+arm64-chromebook (arm64, gcc-12) — FAIL, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- defconfig+kselftest+arm64-chromebook (arm64, clang-16) — FAIL, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- i386_defconfig+kselftest (i386, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- multi_v7_defconfig+kselftest (arm, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- x86_64_defconfig+kselftest (x86_64, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- x86_64_defconfig+kselftest (x86_64, clang-16) — PASS, 0 errors, 1 warning, 0 section mismatches Warnings: vmlinux.o: warning: objtool: set_ftrace_ops_ro+0x39: relocation to !ENDBR: .text+0x14ef94 --- For more info write to <info(a)kernelci.org>

11 months, 3 weeks

1
0
0 0

[PATCH net-next 00/11] mptcp: MIB counters for MPJ TX + misc improvements

by Matthieu Baerts (NGI0)

Recently, a few issues have been discovered around the creation of additional subflows. Without these counters, it was difficult to point out the reason why some subflows were not created as expected. In patch 3, all error paths from __mptcp_subflow_connect() are covered, except the one related to the 'fully established mode', because it can only happen with the userspace PM, which will propagate the error to the userspace in this case (ENOTCONN). These new counters are also verified in the MPTCP Join selftest in patch 6. While at it, a few other patches are improving the MPTCP path-manager code ... - Patch 1: 'flush' related helpers are renamed to avoid confusions - Patch 2: directly pass known ID and flags to create a new subflow, i/o getting them later by iterating over all endpoints again ... and the MPJoin selftests: - Patch 4: reduce the number of positional parameters - Patch 5: only one line for the 'join' checks, instead of 3 - Patch 7: more explicit check names, instead of sometimes too cryptic ones: rtx, ptx, ftx, ctx, fclzrx, sum - Patch 8: specify client/server instead of 'invert' for some checks not suggesting one specific direction - Patch 9: mute errors of mptcp_connect when ran in the background - Patch 10: simplify checksum_tests by using a for-loop - Patch 11: remove 'define' re-definitions Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org> --- Geliang Tang (1): selftests: mptcp: join: simplify checksum_tests Matthieu Baerts (NGI0) (10): mptcp: pm: rename helpers linked to 'flush' mptcp: pm: reduce entries iterations on connect mptcp: MIB counters for sent MP_JOIN selftests: mptcp: join: reduce join_nr params selftests: mptcp: join: one line for join check selftests: mptcp: join: validate MPJ SYN TX MIB counters selftests: mptcp: join: more explicit check name selftests: mptcp: join: specify host being checked selftests: mptcp: join: mute errors when ran in the background selftests: mptcp: pm_nl_ctl: remove re-definition net/mptcp/mib.c | 4 + net/mptcp/mib.h | 4 + net/mptcp/pm.c | 11 - net/mptcp/pm_netlink.c | 78 ++---- net/mptcp/pm_userspace.c | 40 +-- net/mptcp/protocol.h | 16 +- net/mptcp/subflow.c | 50 +++- tools/testing/selftests/net/mptcp/mptcp_join.sh | 350 ++++++++++++++---------- tools/testing/selftests/net/mptcp/pm_nl_ctl.c | 10 +- 9 files changed, 309 insertions(+), 254 deletions(-) --- base-commit: 221f9cce949ac8042f65b71ed1fde13b99073256 change-id: 20240902-net-next-mptcp-mib-mpjtx-misc-d80298438016 Best regards, -- Matthieu Baerts (NGI0) <matttbe(a)kernel.org>

11 months, 3 weeks

2
12
0 0

[PATCH v2] selftests: splice: Add usage() to splice_read.c

by Rong Tao

From: Rong Tao <rongtao(a)cestc.cn> Give the programmer more help information to inform the program on how to use it. Signed-off-by: Rong Tao <rongtao(a)cestc.cn> --- tools/testing/selftests/splice/splice_read.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/splice/splice_read.c b/tools/testing/selftests/splice/splice_read.c index 46dae6a25cfb..73a8bc146f97 100644 --- a/tools/testing/selftests/splice/splice_read.c +++ b/tools/testing/selftests/splice/splice_read.c @@ -9,6 +9,12 @@ #include <sys/types.h> #include <sys/stat.h> +void usage(const char *prog) +{ + fprintf(stderr, "Usage: %s INPUT [BYTES]\n", prog); + fprintf(stderr, " %s /etc/os-release | cat\n", prog); +} + int main(int argc, char *argv[]) { int fd; @@ -16,7 +22,7 @@ int main(int argc, char *argv[]) ssize_t spliced; if (argc < 2) { - fprintf(stderr, "Usage: %s INPUT [BYTES]\n", argv[0]); + usage(argv[0]); return EXIT_FAILURE; } @@ -49,6 +55,7 @@ int main(int argc, char *argv[]) size, SPLICE_F_MOVE); if (spliced < 0) { perror("splice"); + usage(argv[0]); return EXIT_FAILURE; } -- 2.46.0

11 months, 3 weeks

2
1
0 0

[PATCH] selftests/vDSO: support DT_GNU_HASH

by Fangrui Song

glibc added support for DT_GNU_HASH in 2006 and DT_HASH has been obsoleted for more than one decade in many Linux distributions. Many vDSOs support DT_GNU_HASH. This patch adds selftests support. Signed-off-by: Fangrui Song <maskray(a)google.com> --- tools/testing/selftests/vDSO/parse_vdso.c | 105 ++++++++++++++++------ 1 file changed, 79 insertions(+), 26 deletions(-) diff --git a/tools/testing/selftests/vDSO/parse_vdso.c b/tools/testing/selftests/vDSO/parse_vdso.c index 4ae417372e9e..35cb545da13e 100644 --- a/tools/testing/selftests/vDSO/parse_vdso.c +++ b/tools/testing/selftests/vDSO/parse_vdso.c @@ -47,6 +47,7 @@ static struct vdso_info /* Symbol table */ ELF(Sym) *symtab; const char *symstrings; + ELF(Word) *gnu_hash; ELF(Word) *bucket, *chain; ELF(Word) nbucket, nchain; @@ -75,6 +76,16 @@ static unsigned long elf_hash(const char *name) return h; } +static uint32_t gnu_hash(const char *name) +{ + const unsigned char *s = (void *)name; + uint32_t h = 5381; + + for (; *s; s++) + h += h * 32 + *s; + return h; +} + void vdso_init_from_sysinfo_ehdr(uintptr_t base) { size_t i; @@ -117,6 +128,7 @@ void vdso_init_from_sysinfo_ehdr(uintptr_t base) */ ELF(Word) *hash = 0; vdso_info.symstrings = 0; + vdso_info.gnu_hash = 0; vdso_info.symtab = 0; vdso_info.versym = 0; vdso_info.verdef = 0; @@ -137,6 +149,11 @@ void vdso_init_from_sysinfo_ehdr(uintptr_t base) ((uintptr_t)dyn[i].d_un.d_ptr + vdso_info.load_offset); break; + case DT_GNU_HASH: + vdso_info.gnu_hash = + (ELF(Word) *)((uintptr_t)dyn[i].d_un.d_ptr + + vdso_info.load_offset); + break; case DT_VERSYM: vdso_info.versym = (ELF(Versym) *) ((uintptr_t)dyn[i].d_un.d_ptr @@ -149,17 +166,26 @@ void vdso_init_from_sysinfo_ehdr(uintptr_t base) break; } } - if (!vdso_info.symstrings || !vdso_info.symtab || !hash) + if (!vdso_info.symstrings || !vdso_info.symtab || + (!hash && !vdso_info.gnu_hash)) return; /* Failed */ if (!vdso_info.verdef) vdso_info.versym = 0; /* Parse the hash table header. */ - vdso_info.nbucket = hash[0]; - vdso_info.nchain = hash[1]; - vdso_info.bucket = &hash[2]; - vdso_info.chain = &hash[vdso_info.nbucket + 2]; + if (vdso_info.gnu_hash) { + vdso_info.nbucket = vdso_info.gnu_hash[0]; + /* The bucket array is located after the header (4 uint32) and the bloom + filter (size_t array of gnu_hash[2] elements). */ + vdso_info.bucket = vdso_info.gnu_hash + 4 + + sizeof(size_t) / 4 * vdso_info.gnu_hash[2]; + } else { + vdso_info.nbucket = hash[0]; + vdso_info.nchain = hash[1]; + vdso_info.bucket = &hash[2]; + vdso_info.chain = &hash[vdso_info.nbucket + 2]; + } /* That's all we need. */ vdso_info.valid = true; @@ -203,6 +229,26 @@ static bool vdso_match_version(ELF(Versym) ver, && !strcmp(name, vdso_info.symstrings + aux->vda_name); } +static bool check_sym(ELF(Sym) *sym, ELF(Word) i, const char *name, + const char *version, unsigned long ver_hash) +{ + /* Check for a defined global or weak function w/ right name. */ + if (ELF64_ST_TYPE(sym->st_info) != STT_FUNC) + return false; + if (ELF64_ST_BIND(sym->st_info) != STB_GLOBAL && + ELF64_ST_BIND(sym->st_info) != STB_WEAK) + return false; + if (strcmp(name, vdso_info.symstrings + sym->st_name)) + return false; + + /* Check symbol version. */ + if (vdso_info.versym && + !vdso_match_version(vdso_info.versym[i], version, ver_hash)) + return false; + + return true; +} + void *vdso_sym(const char *version, const char *name) { unsigned long ver_hash; @@ -210,29 +256,36 @@ void *vdso_sym(const char *version, const char *name) return 0; ver_hash = elf_hash(version); - ELF(Word) chain = vdso_info.bucket[elf_hash(name) % vdso_info.nbucket]; + ELF(Word) i; - for (; chain != STN_UNDEF; chain = vdso_info.chain[chain]) { - ELF(Sym) *sym = &vdso_info.symtab[chain]; + if (vdso_info.gnu_hash) { + uint32_t h1 = gnu_hash(name), h2, *hashval; - /* Check for a defined global or weak function w/ right name. */ - if (ELF64_ST_TYPE(sym->st_info) != STT_FUNC) - continue; - if (ELF64_ST_BIND(sym->st_info) != STB_GLOBAL && - ELF64_ST_BIND(sym->st_info) != STB_WEAK) - continue; - if (sym->st_shndx == SHN_UNDEF) - continue; - if (strcmp(name, vdso_info.symstrings + sym->st_name)) - continue; - - /* Check symbol version. */ - if (vdso_info.versym - && !vdso_match_version(vdso_info.versym[chain], - version, ver_hash)) - continue; - - return (void *)(vdso_info.load_offset + sym->st_value); + i = vdso_info.bucket[h1 % vdso_info.nbucket]; + if (i == 0) + return 0; + h1 |= 1; + hashval = vdso_info.bucket + vdso_info.nbucket + + (i - vdso_info.gnu_hash[1]); + for (;; i++) { + ELF(Sym) *sym = &vdso_info.symtab[i]; + h2 = *hashval++; + if (h1 == (h2 | 1) && + check_sym(sym, i, name, version, ver_hash)) + return (void *)(vdso_info.load_offset + + sym->st_value); + if (h2 & 1) + break; + } + } else { + i = vdso_info.bucket[elf_hash(name) % vdso_info.nbucket]; + for (; i; i = vdso_info.chain[i]) { + ELF(Sym) *sym = &vdso_info.symtab[i]; + if (sym->st_shndx != SHN_UNDEF && + check_sym(sym, i, name, version, ver_hash)) + return (void *)(vdso_info.load_offset + + sym->st_value); + } } return 0; -- 2.46.0.76.ge559c4bf1a-goog

11 months, 3 weeks

3
5
0 0

[PATCH] selftests: filesystems: fix warn_unused_result build warnings

by Abhinav Jain

Add return value checks for read & write calls in test_listmount_ns function. This patch resolves below compilation warnings: ``` statmount_test_ns.c: In function ‘test_listmount_ns’: statmount_test_ns.c:322:17: warning: ignoring return value of ‘write’ declared with attribute ‘warn_unused_result’ [-Wunused-result] statmount_test_ns.c:323:17: warning: ignoring return value of ‘read’ declared with attribute ‘warn_unused_result’ [-Wunused-result] ``` Signed-off-by: Abhinav Jain <jain.abhinav177(a)gmail.com> --- .../selftests/filesystems/statmount/statmount_test_ns.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c b/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c index e044f5fc57fd..70cb0c8b21cf 100644 --- a/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c +++ b/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c @@ -319,8 +319,11 @@ static void test_listmount_ns(void) * Tell our parent how many mounts we have, and then wait for it * to tell us we're done. */ - write(child_ready_pipe[1], &nr_mounts, sizeof(nr_mounts)); - read(parent_ready_pipe[0], &cval, sizeof(cval)); + if (write(child_ready_pipe[1], &nr_mounts, sizeof(nr_mounts)) != + sizeof(nr_mounts)) + ret = NSID_ERROR; + if (read(parent_ready_pipe[0], &cval, sizeof(cval)) != sizeof(cval)) + ret = NSID_ERROR; exit(NSID_PASS); } -- 2.34.1

11 months, 3 weeks

2
2
0 0

[PATCH] selftests: net: convert comma to semicolon

by Chen Ni

Replace a comma between expression statements by a semicolon. Signed-off-by: Chen Ni <nichen(a)iscas.ac.cn> --- tools/testing/selftests/net/psock_fanout.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/net/psock_fanout.c b/tools/testing/selftests/net/psock_fanout.c index 1a736f700be4..4f31e92ebd96 100644 --- a/tools/testing/selftests/net/psock_fanout.c +++ b/tools/testing/selftests/net/psock_fanout.c @@ -165,9 +165,9 @@ static void sock_fanout_set_ebpf(int fd) attr.insns = (unsigned long) prog; attr.insn_cnt = ARRAY_SIZE(prog); attr.license = (unsigned long) "GPL"; - attr.log_buf = (unsigned long) log_buf, - attr.log_size = sizeof(log_buf), - attr.log_level = 1, + attr.log_buf = (unsigned long) log_buf; + attr.log_size = sizeof(log_buf); + attr.log_level = 1; pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr)); if (pfd < 0) { -- 2.25.1

11 months, 3 weeks

2
1
0 0

[PATCH v3 0/3] RISC-V: mm: do not treat hint addr on mmap as the upper bound to search

by Yangyu Chen

Previous patch series[1][2] changes a mmap behavior that treats the hint address as the upper bound of the mmap address range. The motivation of the previous patch series is that some user space software may assume 48-bit address space and use higher bits to encode some information, which may collide with large virtual address space mmap may return. However, to make sv48 by default, we don't need to change the meaning of the hint address on mmap as the upper bound of the mmap address range. This behavior breaks some user space software like Chromium that gets ENOMEM error when the hint address + size is not big enough, as specified in [3]. Other ISAs with larger than 48-bit virtual address space like x86, arm64, and powerpc do not have this special mmap behavior on hint address. They all just make 48-bit / 47-bit virtual address space by default, and if a user space software wants to large virtual address space, it only need to specify a hint address larger than 48-bit / 47-bit. Thus, this patch series change mmap to use sv48 by default but does not treat the hint address as the upper bound of the mmap address range. After this patch, the behavior of mmap will align with existing behavior on other ISAs with larger than 48-bit virtual address space like x86, arm64, and powerpc. The user space software will no longer need to rewrite their code to fit with this special mmap behavior only on RISC-V. Note: Charlie also created another series [4] to completely remove the arch_get_mmap_end and arch_get_mmap_base behavior based on the hint address and size. However, this will cause programs like Go and Java, which need to store information in the higher bits of the pointer, to fail on Sv57 machines. Changes in v3: - Rebase to newest master - Changes some information in cover letter after patchset [2] - Use patch [5] to patch selftests - Link to v2: https://lore.kernel.org/linux-riscv/tencent_B2D0435BC011135736262764B511994… Changes in v2: - correct arch_get_mmap_end and arch_get_mmap_base - Add description in documentation about mmap behavior on kernel v6.6-6.7. - Improve commit message and cover letter - Rebase to newest riscv/for-next branch - Link to v1: https://lore.kernel.org/linux-riscv/tencent_F3B3B5AB1C9D704763CA423E1A41F8B… [1] https://lore.kernel.org/linux-riscv/20230809232218.849726-1-charlie@rivosin… [2] https://lore.kernel.org/linux-riscv/20240130-use_mmap_hint_address-v3-0-8a6… [3] https://lore.kernel.org/linux-riscv/MEYP282MB2312A08FF95D44014AB78411C68D2@… [4] https://lore.kernel.org/linux-riscv/20240826-riscv_mmap-v1-0-cd8962afe47f@r… [5] https://lore.kernel.org/linux-riscv/20240826-riscv_mmap-v1-2-cd8962afe47f@r… Charlie Jenkins (1): riscv: selftests: Remove mmap hint address checks Yangyu Chen (2): RISC-V: mm: not use hint addr as upper bound Documentation: riscv: correct sv57 kernel behavior Documentation/arch/riscv/vm-layout.rst | 43 ++++++++---- arch/riscv/include/asm/processor.h | 20 ++---- .../selftests/riscv/mm/mmap_bottomup.c | 2 - .../testing/selftests/riscv/mm/mmap_default.c | 2 - tools/testing/selftests/riscv/mm/mmap_test.h | 67 ------------------- 5 files changed, 36 insertions(+), 98 deletions(-) -- 2.45.2

11 months, 3 weeks

4
9
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-kselftest-mirror September 2024