From a09074228977c24c677c10282f506fa11f88eb93 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 1 Aug 2024 18:39:28 +0200 Subject: [PATCH 01/16] thermal: core: Update thermal zone registration documentation The thermal sysfs API document is outdated. One of the problems with it is that is still documents thermal_zone_device_register() which does not exit any more and it does not reflect the current thermal zone operations definition. Replace the thermal_zone_device_register() description in it with a thermal_zone_device_register_with_trips() description, including an update of the thermal zone operations list. Signed-off-by: Rafael J. Wysocki Reviewed-by: Lukasz Luba Link: https://patch.msgid.link/2767845.mvXUDI8C0e@rjwysocki.net --- .../driver-api/thermal/sysfs-api.rst | 65 +++++++++---------- 1 file changed, 30 insertions(+), 35 deletions(-) diff --git a/Documentation/driver-api/thermal/sysfs-api.rst b/Documentation/driver-api/thermal/sysfs-api.rst index 6c1175c6afba..978198f8a18b 100644 --- a/Documentation/driver-api/thermal/sysfs-api.rst +++ b/Documentation/driver-api/thermal/sysfs-api.rst @@ -4,8 +4,6 @@ Generic Thermal Sysfs driver How To Written by Sujith Thomas , Zhang Rui -Updated: 2 January 2008 - Copyright (c) 2008 Intel Corporation @@ -38,23 +36,23 @@ temperature) and throttle appropriate devices. :: - struct thermal_zone_device - *thermal_zone_device_register(char *type, - int trips, int mask, void *devdata, - struct thermal_zone_device_ops *ops, - const struct thermal_zone_params *tzp, - int passive_delay, int polling_delay)) + struct thermal_zone_device * + thermal_zone_device_register_with_trips(const char *type, + const struct thermal_trip *trips, + int num_trips, void *devdata, + const struct thermal_zone_device_ops *ops, + const struct thermal_zone_params *tzp, + unsigned int passive_delay, + unsigned int polling_delay) - This interface function adds a new thermal zone device (sensor) to + This interface function adds a new thermal zone device (sensor) to the /sys/class/thermal folder as `thermal_zone[0-*]`. It tries to bind all the - thermal cooling devices registered at the same time. + thermal cooling devices registered to it at the same time. type: the thermal zone type. trips: - the total number of trip points this thermal zone supports. - mask: - Bit string: If 'n'th bit is set, then trip point 'n' is writable. + the table of trip points for this thermal zone. devdata: device private data ops: @@ -67,32 +65,29 @@ temperature) and throttle appropriate devices. .get_temp: get the current temperature of the thermal zone. .set_trips: - set the trip points window. Whenever the current temperature - is updated, the trip points immediately below and above the - current temperature are found. - .get_mode: - get the current mode (enabled/disabled) of the thermal zone. - - - "enabled" means the kernel thermal management is - enabled. - - "disabled" will prevent kernel thermal driver action - upon trip points so that user applications can take - charge of thermal management. - .set_mode: - set the mode (enabled/disabled) of the thermal zone. - .get_trip_type: - get the type of certain trip point. - .get_trip_temp: - get the temperature above which the certain trip point - will be fired. + set the trip points window. Whenever the current temperature + is updated, the trip points immediately below and above the + current temperature are found. + .change_mode: + change the mode (enabled/disabled) of the thermal zone. + .set_trip_temp: + set the temperature of a given trip point. + .get_crit_temp: + get the critical temperature for this thermal zone. .set_emul_temp: - set the emulation temperature which helps in debugging - different threshold temperature points. + set the emulation temperature which helps in debugging + different threshold temperature points. + .get_trend: + get the trend of most recent zone temperature changes. + .hot: + hot trip point crossing handler. + .critical: + critical trip point crossing handler. tzp: thermal zone platform parameters. passive_delay: - number of milliseconds to wait between polls when - performing passive cooling. + number of milliseconds to wait between polls when performing passive + cooling. polling_delay: number of milliseconds to wait between polls when checking whether trip points have been crossed (0 for interrupt driven systems). -- 2.50.1 From 54233a4254036efca91b9bffbd398ecf39e90555 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 30 Jul 2024 17:30:40 +0200 Subject: [PATCH 02/16] uretprobe: change syscall number, again Despite multiple attempts to get the syscall number assignment right for the newly added uretprobe syscall, we ended up with a bit of a mess: - The number is defined as 467 based on the assumption that the xattrat family of syscalls would use 463 through 466, but those did not make it into 6.11. - The include/uapi/asm-generic/unistd.h file still lists the number 463, but the new scripts/syscall.tbl that was supposed to have the same data lists 467 instead as the number for arc, arm64, csky, hexagon, loongarch, nios2, openrisc and riscv. None of these architectures actually provide a uretprobe syscall. - All the other architectures (powerpc, arm, mips, ...) don't list this syscall at all. There are two ways to make it consistent again: either list it with the same syscall number on all architectures, or only list it on x86 but not in scripts/syscall.tbl and asm-generic/unistd.h. Based on the most recent discussion, it seems like we won't need it anywhere else, so just remove the inconsistent assignment and instead move the x86 number to the next available one in the architecture specific range, which is 335. Fixes: 5c28424e9a34 ("syscalls: Fix to add sys_uretprobe to syscall.tbl") Fixes: 190fec72df4a ("uprobe: Wire up uretprobe system call") Fixes: 63ded110979b ("uprobe: Change uretprobe syscall scope and number") Acked-by: Masami Hiramatsu (Google) Reviewed-by: Jiri Olsa Signed-off-by: Arnd Bergmann --- arch/x86/entry/syscalls/syscall_64.tbl | 2 +- include/uapi/asm-generic/unistd.h | 5 +---- scripts/syscall.tbl | 1 - tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c | 2 +- 4 files changed, 3 insertions(+), 7 deletions(-) diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 83073fa3c989..7093ee21c0d1 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -344,6 +344,7 @@ 332 common statx sys_statx 333 common io_pgetevents sys_io_pgetevents 334 common rseq sys_rseq +335 common uretprobe sys_uretprobe # don't use numbers 387 through 423, add new calls after the last # 'common' entry 424 common pidfd_send_signal sys_pidfd_send_signal @@ -385,7 +386,6 @@ 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules 462 common mseal sys_mseal -467 common uretprobe sys_uretprobe # # Due to a historical design error, certain syscalls are numbered differently diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 985a262d0f9e..5bf6148cac2b 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -841,11 +841,8 @@ __SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules) #define __NR_mseal 462 __SYSCALL(__NR_mseal, sys_mseal) -#define __NR_uretprobe 463 -__SYSCALL(__NR_uretprobe, sys_uretprobe) - #undef __NR_syscalls -#define __NR_syscalls 464 +#define __NR_syscalls 463 /* * 32 bit systems traditionally used different diff --git a/scripts/syscall.tbl b/scripts/syscall.tbl index 591d85e8ca7e..797e20ea99a2 100644 --- a/scripts/syscall.tbl +++ b/scripts/syscall.tbl @@ -402,4 +402,3 @@ 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules 462 common mseal sys_mseal -467 common uretprobe sys_uretprobe diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c index bd8c75b620c2..5f78edca6540 100644 --- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c +++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c @@ -216,7 +216,7 @@ static void test_uretprobe_regs_change(void) } #ifndef __NR_uretprobe -#define __NR_uretprobe 467 +#define __NR_uretprobe 335 #endif __naked unsigned long uretprobe_syscall_call_1(void) -- 2.50.1 From 343416f0c11c42bed07f6db03ca599f4f1771b17 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 1 Aug 2024 14:27:23 +0200 Subject: [PATCH 03/16] syscalls: fix syscall macros for newfstat/newfstatat The __NR_newfstat and __NR_newfstatat macros accidentally got renamed in the conversion to the syscall.tbl format, dropping the 'new' portion of the name. In an unrelated change, the two syscalls are no longer architecture specific but are once more defined on all 64-bit architectures, so the 'newstat' ABI keyword can be dropped from the table as a simplification. Fixes: Fixes: 4fe53bf2ba0a ("syscalls: add generic scripts/syscall.tbl") Closes: https://lore.kernel.org/lkml/838053e0-b186-4e9f-9668-9a3384a71f23@app.fastmail.com/T/#t Reported-by: Florian Weimer Signed-off-by: Arnd Bergmann --- arch/arm64/kernel/Makefile.syscalls | 2 +- arch/loongarch/kernel/Makefile.syscalls | 3 ++- arch/riscv/kernel/Makefile.syscalls | 2 +- scripts/syscall.tbl | 4 ++-- 4 files changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kernel/Makefile.syscalls b/arch/arm64/kernel/Makefile.syscalls index 3cfafd003b2d..0542a718871a 100644 --- a/arch/arm64/kernel/Makefile.syscalls +++ b/arch/arm64/kernel/Makefile.syscalls @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 syscall_abis_32 += -syscall_abis_64 += renameat newstat rlimit memfd_secret +syscall_abis_64 += renameat rlimit memfd_secret syscalltbl = arch/arm64/tools/syscall_%.tbl diff --git a/arch/loongarch/kernel/Makefile.syscalls b/arch/loongarch/kernel/Makefile.syscalls index 523bb411a3bc..ab7d9baa2915 100644 --- a/arch/loongarch/kernel/Makefile.syscalls +++ b/arch/loongarch/kernel/Makefile.syscalls @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 -syscall_abis_64 += newstat +# No special ABIs on loongarch so far +syscall_abis_64 += diff --git a/arch/riscv/kernel/Makefile.syscalls b/arch/riscv/kernel/Makefile.syscalls index 52087a023b3d..9668fd1faf60 100644 --- a/arch/riscv/kernel/Makefile.syscalls +++ b/arch/riscv/kernel/Makefile.syscalls @@ -1,4 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 syscall_abis_32 += riscv memfd_secret -syscall_abis_64 += riscv newstat rlimit memfd_secret +syscall_abis_64 += riscv rlimit memfd_secret diff --git a/scripts/syscall.tbl b/scripts/syscall.tbl index 797e20ea99a2..4586a18dfe9b 100644 --- a/scripts/syscall.tbl +++ b/scripts/syscall.tbl @@ -98,9 +98,9 @@ 77 common tee sys_tee 78 common readlinkat sys_readlinkat 79 stat64 fstatat64 sys_fstatat64 -79 newstat fstatat sys_newfstatat +79 64 newfstatat sys_newfstatat 80 stat64 fstat64 sys_fstat64 -80 newstat fstat sys_newfstat +80 64 newfstat sys_newfstat 81 common sync sys_sync 82 common fsync sys_fsync 83 common fdatasync sys_fdatasync -- 2.50.1 From cfb00a35786414e7c0e6226b277d9f09657eae74 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Wed, 31 Jul 2024 14:36:01 +0100 Subject: [PATCH 04/16] arm64: jump_label: Ensure patched jump_labels are visible to all CPUs Although the Arm architecture permits concurrent modification and execution of NOP and branch instructions, it still requires some synchronisation to ensure that other CPUs consistently execute the newly written instruction: > When the modified instructions are observable, each PE that is > executing the modified instructions must execute an ISB or perform a > context synchronizing event to ensure execution of the modified > instructions Prior to commit f6cc0c501649 ("arm64: Avoid calling stop_machine() when patching jump labels"), the arm64 jump_label patching machinery performed synchronisation using stop_machine() after each modification, however this was problematic when flipping static keys from atomic contexts (namely, the arm_arch_timer CPU hotplug startup notifier) and so we switched to the _nosync() patching routines to avoid "scheduling while atomic" BUG()s during boot. In hindsight, the analysis of the issue in f6cc0c501649 isn't quite right: it cites the use of IPIs in the default patching routines as the cause of the lockup, whereas stop_machine() does not rely on IPIs and the I-cache invalidation is performed using __flush_icache_range(), which elides the call to kick_all_cpus_sync(). In fact, the blocking wait for other CPUs is what triggers the BUG() and the problem remains even after f6cc0c501649, for example because we could block on the jump_label_mutex. Eventually, the arm_arch_timer driver was fixed to avoid the static key entirely in commit a862fc2254bd ("clocksource/arm_arch_timer: Remove use of workaround static key"). This all leaves the jump_label patching code in a funny situation on arm64 as we do not synchronise with other CPUs to reduce the likelihood of a bug which no longer exists. Consequently, toggling a static key on one CPU cannot be assumed to take effect on other CPUs, leading to potential issues, for example with missing preempt notifiers. Rather than revert f6cc0c501649 and go back to stop_machine() for each patch site, implement arch_jump_label_transform_apply() and kick all the other CPUs with an IPI at the end of patching. Cc: Alexander Potapenko Cc: Mark Rutland Cc: Marc Zyngier Fixes: f6cc0c501649 ("arm64: Avoid calling stop_machine() when patching jump labels") Signed-off-by: Will Deacon Reviewed-by: Catalin Marinas Reviewed-by: Marc Zyngier Link: https://lore.kernel.org/r/20240731133601.3073-1-will@kernel.org Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/jump_label.h | 1 + arch/arm64/kernel/jump_label.c | 11 +++++++++-- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/jump_label.h b/arch/arm64/include/asm/jump_label.h index 4e753908b801..a0a5bbae7229 100644 --- a/arch/arm64/include/asm/jump_label.h +++ b/arch/arm64/include/asm/jump_label.h @@ -13,6 +13,7 @@ #include #include +#define HAVE_JUMP_LABEL_BATCH #define JUMP_LABEL_NOP_SIZE AARCH64_INSN_SIZE #define JUMP_TABLE_ENTRY(key, label) \ diff --git a/arch/arm64/kernel/jump_label.c b/arch/arm64/kernel/jump_label.c index faf88ec9c48e..f63ea915d6ad 100644 --- a/arch/arm64/kernel/jump_label.c +++ b/arch/arm64/kernel/jump_label.c @@ -7,11 +7,12 @@ */ #include #include +#include #include #include -void arch_jump_label_transform(struct jump_entry *entry, - enum jump_label_type type) +bool arch_jump_label_transform_queue(struct jump_entry *entry, + enum jump_label_type type) { void *addr = (void *)jump_entry_code(entry); u32 insn; @@ -25,4 +26,10 @@ void arch_jump_label_transform(struct jump_entry *entry, } aarch64_insn_patch_text_nosync(addr, insn); + return true; +} + +void arch_jump_label_transform_apply(void) +{ + kick_all_cpus_sync(); } -- 2.50.1 From 4b96024ef2296b1d323af327cae5e52809b61420 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Wed, 31 Jul 2024 10:23:39 -0300 Subject: [PATCH 05/16] smb: client: handle lack of FSCTL_GET_REPARSE_POINT support As per MS-FSA 2.1.5.10.14, support for FSCTL_GET_REPARSE_POINT is optional and if the server doesn't support it, STATUS_INVALID_DEVICE_REQUEST must be returned for the operation. If we find files with reparse points and we can't read them due to lack of client or server support, just ignore it and then treat them as regular files or junctions. Fixes: 5f71ebc41294 ("smb: client: parse reparse point flag in create response") Reported-by: Sebastian Steinbeisser Tested-by: Sebastian Steinbeisser Acked-by: Tom Talpey Signed-off-by: Paulo Alcantara (Red Hat) Signed-off-by: Steve French --- fs/smb/client/inode.c | 17 +++++++++++++++-- fs/smb/client/reparse.c | 4 ++++ fs/smb/client/reparse.h | 19 +++++++++++++++++-- fs/smb/client/smb2inode.c | 2 ++ 4 files changed, 38 insertions(+), 4 deletions(-) diff --git a/fs/smb/client/inode.c b/fs/smb/client/inode.c index 4a8aa1de9522..dd0afa23734c 100644 --- a/fs/smb/client/inode.c +++ b/fs/smb/client/inode.c @@ -1042,13 +1042,26 @@ static int reparse_info_to_fattr(struct cifs_open_info_data *data, } rc = -EOPNOTSUPP; - switch ((data->reparse.tag = tag)) { - case 0: /* SMB1 symlink */ + data->reparse.tag = tag; + if (!data->reparse.tag) { if (server->ops->query_symlink) { rc = server->ops->query_symlink(xid, tcon, cifs_sb, full_path, &data->symlink_target); } + if (rc == -EOPNOTSUPP) + data->reparse.tag = IO_REPARSE_TAG_INTERNAL; + } + + switch (data->reparse.tag) { + case 0: /* SMB1 symlink */ + break; + case IO_REPARSE_TAG_INTERNAL: + rc = 0; + if (le32_to_cpu(data->fi.Attributes) & ATTR_DIRECTORY) { + cifs_create_junction_fattr(fattr, sb); + goto out; + } break; case IO_REPARSE_TAG_MOUNT_POINT: cifs_create_junction_fattr(fattr, sb); diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c index a0ffbda90733..689d8a506d45 100644 --- a/fs/smb/client/reparse.c +++ b/fs/smb/client/reparse.c @@ -505,6 +505,10 @@ bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb, } switch (tag) { + case IO_REPARSE_TAG_INTERNAL: + if (!(fattr->cf_cifsattrs & ATTR_DIRECTORY)) + return false; + fallthrough; case IO_REPARSE_TAG_DFS: case IO_REPARSE_TAG_DFSR: case IO_REPARSE_TAG_MOUNT_POINT: diff --git a/fs/smb/client/reparse.h b/fs/smb/client/reparse.h index 6b55d1df9e2f..2c0644bc4e65 100644 --- a/fs/smb/client/reparse.h +++ b/fs/smb/client/reparse.h @@ -12,6 +12,12 @@ #include "fs_context.h" #include "cifsglob.h" +/* + * Used only by cifs.ko to ignore reparse points from files when client or + * server doesn't support FSCTL_GET_REPARSE_POINT. + */ +#define IO_REPARSE_TAG_INTERNAL ((__u32)~0U) + static inline dev_t reparse_nfs_mkdev(struct reparse_posix_data *buf) { u64 v = le64_to_cpu(*(__le64 *)buf->DataBuffer); @@ -78,10 +84,19 @@ static inline u32 reparse_mode_wsl_tag(mode_t mode) static inline bool reparse_inode_match(struct inode *inode, struct cifs_fattr *fattr) { + struct cifsInodeInfo *cinode = CIFS_I(inode); struct timespec64 ctime = inode_get_ctime(inode); - return (CIFS_I(inode)->cifsAttrs & ATTR_REPARSE) && - CIFS_I(inode)->reparse_tag == fattr->cf_cifstag && + /* + * Do not match reparse tags when client or server doesn't support + * FSCTL_GET_REPARSE_POINT. @fattr->cf_cifstag should contain correct + * reparse tag from query dir response but the client won't be able to + * read the reparse point data anyway. This spares us a revalidation. + */ + if (cinode->reparse_tag != IO_REPARSE_TAG_INTERNAL && + cinode->reparse_tag != fattr->cf_cifstag) + return false; + return (cinode->cifsAttrs & ATTR_REPARSE) && timespec64_equal(&ctime, &fattr->cf_ctime); } diff --git a/fs/smb/client/smb2inode.c b/fs/smb/client/smb2inode.c index 5c02a12251c8..062b86a4936f 100644 --- a/fs/smb/client/smb2inode.c +++ b/fs/smb/client/smb2inode.c @@ -930,6 +930,8 @@ int smb2_query_path_info(const unsigned int xid, switch (rc) { case 0: + rc = parse_create_response(data, cifs_sb, &out_iov[0]); + break; case -EOPNOTSUPP: /* * BB TODO: When support for special files added to Samba -- 2.50.1 From cd936507986e38535e7c98940c186e9a97b87184 Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 31 Jul 2024 11:30:00 +0100 Subject: [PATCH 06/16] cifs: Remove cifs_aio_ctx Remove struct cifs_aio_ctx and its associated alloc/release functions as it is no longer used, the functions being taken over by netfslib. Signed-off-by: David Howells cc: Steve French cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French --- fs/smb/client/cifsglob.h | 24 ----------------- fs/smb/client/cifsproto.h | 2 -- fs/smb/client/misc.c | 54 --------------------------------------- 3 files changed, 80 deletions(-) diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h index 8e86fec7dcd2..f6d1f075987f 100644 --- a/fs/smb/client/cifsglob.h +++ b/fs/smb/client/cifsglob.h @@ -1471,29 +1471,6 @@ struct cifs_io_parms { struct TCP_Server_Info *server; }; -struct cifs_aio_ctx { - struct kref refcount; - struct list_head list; - struct mutex aio_mutex; - struct completion done; - struct iov_iter iter; - struct kiocb *iocb; - struct cifsFileInfo *cfile; - struct bio_vec *bv; - loff_t pos; - unsigned int nr_pinned_pages; - ssize_t rc; - unsigned int len; - unsigned int total_len; - unsigned int bv_need_unpin; /* If ->bv[] needs unpinning */ - bool should_dirty; - /* - * Indicates if this aio_ctx is for direct_io, - * If yes, iter is a copy of the user passed iov_iter - */ - bool direct_io; -}; - struct cifs_io_request { struct netfs_io_request rreq; struct cifsFileInfo *cfile; @@ -2010,7 +1987,6 @@ require use of the stronger protocol */ * cifsFileInfo->file_info_lock cifsFileInfo->count cifs_new_fileinfo * ->invalidHandle initiate_cifs_search * ->oplock_break_cancelled - * cifs_aio_ctx->aio_mutex cifs_aio_ctx cifs_aio_ctx_alloc ****************************************************************************/ #ifdef DECLARE_GLOBALS_HERE diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h index c15bb5ee7eb7..497bf3c447bc 100644 --- a/fs/smb/client/cifsproto.h +++ b/fs/smb/client/cifsproto.h @@ -619,8 +619,6 @@ int __cifs_calc_signature(struct smb_rqst *rqst, struct shash_desc *shash); enum securityEnum cifs_select_sectype(struct TCP_Server_Info *, enum securityEnum); -struct cifs_aio_ctx *cifs_aio_ctx_alloc(void); -void cifs_aio_ctx_release(struct kref *refcount); int cifs_alloc_hash(const char *name, struct shash_desc **sdesc); void cifs_free_hash(struct shash_desc **sdesc); diff --git a/fs/smb/client/misc.c b/fs/smb/client/misc.c index 07c468ddb88a..b28ff62f1f15 100644 --- a/fs/smb/client/misc.c +++ b/fs/smb/client/misc.c @@ -995,60 +995,6 @@ parse_DFS_referrals_exit: return rc; } -struct cifs_aio_ctx * -cifs_aio_ctx_alloc(void) -{ - struct cifs_aio_ctx *ctx; - - /* - * Must use kzalloc to initialize ctx->bv to NULL and ctx->direct_io - * to false so that we know when we have to unreference pages within - * cifs_aio_ctx_release() - */ - ctx = kzalloc(sizeof(struct cifs_aio_ctx), GFP_KERNEL); - if (!ctx) - return NULL; - - INIT_LIST_HEAD(&ctx->list); - mutex_init(&ctx->aio_mutex); - init_completion(&ctx->done); - kref_init(&ctx->refcount); - return ctx; -} - -void -cifs_aio_ctx_release(struct kref *refcount) -{ - struct cifs_aio_ctx *ctx = container_of(refcount, - struct cifs_aio_ctx, refcount); - - cifsFileInfo_put(ctx->cfile); - - /* - * ctx->bv is only set if setup_aio_ctx_iter() was call successfuly - * which means that iov_iter_extract_pages() was a success and thus - * that we may have references or pins on pages that we need to - * release. - */ - if (ctx->bv) { - if (ctx->should_dirty || ctx->bv_need_unpin) { - unsigned int i; - - for (i = 0; i < ctx->nr_pinned_pages; i++) { - struct page *page = ctx->bv[i].bv_page; - - if (ctx->should_dirty) - set_page_dirty(page); - if (ctx->bv_need_unpin) - unpin_user_page(page); - } - } - kvfree(ctx->bv); - } - - kfree(ctx); -} - /** * cifs_alloc_hash - allocate hash and hash context together * @name: The name of the crypto hash algo -- 2.50.1 From 69ca1f57555f74142a4c241703c307cb31b54667 Mon Sep 17 00:00:00 2001 From: Steve French Date: Tue, 30 Jul 2024 00:26:21 -0500 Subject: [PATCH 07/16] smb3: add dynamic tracepoints for shutdown ioctl For debugging an umount failure in xfstests generic/043 generic/044 in some configurations, we needed more information on the shutdown ioctl which was suspected of being related to the cause, so tracepoints are added in this patch e.g. "trace-cmd record -e smb3_shutdown_enter -e smb3_shutdown_done -e smb3_shutdown_err" Sample output: godown-47084 [011] ..... 3313.756965: smb3_shutdown_enter: flags=0x1 tid=0x733b3e75 godown-47084 [011] ..... 3313.756968: smb3_shutdown_done: flags=0x1 tid=0x733b3e75 Tested-by: Anthony Nandaa (Microsoft) Signed-off-by: Steve French --- fs/smb/client/ioctl.c | 32 +++++++++++++++++++++------ fs/smb/client/trace.h | 51 ++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 75 insertions(+), 8 deletions(-) diff --git a/fs/smb/client/ioctl.c b/fs/smb/client/ioctl.c index 855ac5a62edf..44dbaf9929a4 100644 --- a/fs/smb/client/ioctl.c +++ b/fs/smb/client/ioctl.c @@ -170,7 +170,10 @@ static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon, static int cifs_shutdown(struct super_block *sb, unsigned long arg) { struct cifs_sb_info *sbi = CIFS_SB(sb); + struct tcon_link *tlink; + struct cifs_tcon *tcon; __u32 flags; + int rc; if (!capable(CAP_SYS_ADMIN)) return -EPERM; @@ -178,14 +181,21 @@ static int cifs_shutdown(struct super_block *sb, unsigned long arg) if (get_user(flags, (__u32 __user *)arg)) return -EFAULT; - if (flags > CIFS_GOING_FLAGS_NOLOGFLUSH) - return -EINVAL; + tlink = cifs_sb_tlink(sbi); + if (IS_ERR(tlink)) + return PTR_ERR(tlink); + tcon = tlink_tcon(tlink); + + trace_smb3_shutdown_enter(flags, tcon->tid); + if (flags > CIFS_GOING_FLAGS_NOLOGFLUSH) { + rc = -EINVAL; + goto shutdown_out_err; + } if (cifs_forced_shutdown(sbi)) - return 0; + goto shutdown_good; cifs_dbg(VFS, "shut down requested (%d)", flags); -/* trace_cifs_shutdown(sb, flags);*/ /* * see: @@ -201,7 +211,8 @@ static int cifs_shutdown(struct super_block *sb, unsigned long arg) */ case CIFS_GOING_FLAGS_DEFAULT: cifs_dbg(FYI, "shutdown with default flag not supported\n"); - return -EINVAL; + rc = -EINVAL; + goto shutdown_out_err; /* * FLAGS_LOGFLUSH is easy since it asks to write out metadata (not * data) but metadata writes are not cached on the client, so can treat @@ -210,11 +221,18 @@ static int cifs_shutdown(struct super_block *sb, unsigned long arg) case CIFS_GOING_FLAGS_LOGFLUSH: case CIFS_GOING_FLAGS_NOLOGFLUSH: sbi->mnt_cifs_flags |= CIFS_MOUNT_SHUTDOWN; - return 0; + goto shutdown_good; default: - return -EINVAL; + rc = -EINVAL; + goto shutdown_out_err; } + +shutdown_good: + trace_smb3_shutdown_done(flags, tcon->tid); return 0; +shutdown_out_err: + trace_smb3_shutdown_err(rc, flags, tcon->tid); + return rc; } static int cifs_dump_full_key(struct cifs_tcon *tcon, struct smb3_full_key_debug_info __user *in) diff --git a/fs/smb/client/trace.h b/fs/smb/client/trace.h index 6b3bdfb97211..0f0c10c7ada7 100644 --- a/fs/smb/client/trace.h +++ b/fs/smb/client/trace.h @@ -1388,7 +1388,7 @@ DECLARE_EVENT_CLASS(smb3_ioctl_class, __entry->command = command; ), TP_printk("xid=%u fid=0x%llx ioctl cmd=0x%x", - __entry->xid, __entry->fid, __entry->command) + __entry->xid, __entry->fid, __entry->command) ) #define DEFINE_SMB3_IOCTL_EVENT(name) \ @@ -1400,9 +1400,58 @@ DEFINE_EVENT(smb3_ioctl_class, smb3_##name, \ DEFINE_SMB3_IOCTL_EVENT(ioctl); +DECLARE_EVENT_CLASS(smb3_shutdown_class, + TP_PROTO(__u32 flags, + __u32 tid), + TP_ARGS(flags, tid), + TP_STRUCT__entry( + __field(__u32, flags) + __field(__u32, tid) + ), + TP_fast_assign( + __entry->flags = flags; + __entry->tid = tid; + ), + TP_printk("flags=0x%x tid=0x%x", + __entry->flags, __entry->tid) +) + +#define DEFINE_SMB3_SHUTDOWN_EVENT(name) \ +DEFINE_EVENT(smb3_shutdown_class, smb3_##name, \ + TP_PROTO(__u32 flags, \ + __u32 tid), \ + TP_ARGS(flags, tid)) + +DEFINE_SMB3_SHUTDOWN_EVENT(shutdown_enter); +DEFINE_SMB3_SHUTDOWN_EVENT(shutdown_done); +DECLARE_EVENT_CLASS(smb3_shutdown_err_class, + TP_PROTO(int rc, + __u32 flags, + __u32 tid), + TP_ARGS(rc, flags, tid), + TP_STRUCT__entry( + __field(int, rc) + __field(__u32, flags) + __field(__u32, tid) + ), + TP_fast_assign( + __entry->rc = rc; + __entry->flags = flags; + __entry->tid = tid; + ), + TP_printk("rc=%d flags=0x%x tid=0x%x", + __entry->rc, __entry->flags, __entry->tid) +) +#define DEFINE_SMB3_SHUTDOWN_ERR_EVENT(name) \ +DEFINE_EVENT(smb3_shutdown_err_class, smb3_##name, \ + TP_PROTO(int rc, \ + __u32 flags, \ + __u32 tid), \ + TP_ARGS(rc, flags, tid)) +DEFINE_SMB3_SHUTDOWN_ERR_EVENT(shutdown_err); DECLARE_EVENT_CLASS(smb3_credit_class, TP_PROTO(__u64 currmid, -- 2.50.1 From ddecea00f87f0c46e9c8339a7c89fb2ff891521a Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Thu, 1 Aug 2024 18:12:39 -0300 Subject: [PATCH 08/16] smb: client: fix FSCTL_GET_REPARSE_POINT against NetApp NetApp server requires the file to be open with FILE_READ_EA access in order to support FSCTL_GET_REPARSE_POINT, otherwise it will return STATUS_INVALID_DEVICE_REQUEST. It doesn't make any sense because there's no requirement for FILE_READ_EA bit to be set nor STATUS_INVALID_DEVICE_REQUEST being used for something other than "unsupported reparse points" in MS-FSA. To fix it and improve compatibility, set FILE_READ_EA & SYNCHRONIZE bits to match what Windows client currently does. Tested-by: Sebastian Steinbeisser Acked-by: Tom Talpey Signed-off-by: Paulo Alcantara (Red Hat) Signed-off-by: Steve French --- fs/smb/client/smb2inode.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/smb/client/smb2inode.c b/fs/smb/client/smb2inode.c index 062b86a4936f..9f5bc41433c1 100644 --- a/fs/smb/client/smb2inode.c +++ b/fs/smb/client/smb2inode.c @@ -950,7 +950,8 @@ int smb2_query_path_info(const unsigned int xid, cmds[num_cmds++] = SMB2_OP_GET_REPARSE; oparms = CIFS_OPARMS(cifs_sb, tcon, full_path, - FILE_READ_ATTRIBUTES | FILE_READ_EA, + FILE_READ_ATTRIBUTES | + FILE_READ_EA | SYNCHRONIZE, FILE_OPEN, create_options | OPEN_REPARSE_POINT, ACL_NO_MODE); cifs_get_readable_path(tcon, full_path, &cfile); @@ -1258,7 +1259,8 @@ int smb2_query_reparse_point(const unsigned int xid, cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path); cifs_get_readable_path(tcon, full_path, &cfile); - oparms = CIFS_OPARMS(cifs_sb, tcon, full_path, FILE_READ_ATTRIBUTES, + oparms = CIFS_OPARMS(cifs_sb, tcon, full_path, + FILE_READ_ATTRIBUTES | FILE_READ_EA | SYNCHRONIZE, FILE_OPEN, OPEN_REPARSE_POINT, ACL_NO_MODE); rc = smb2_compound_op(xid, tcon, cifs_sb, full_path, &oparms, &in_iov, -- 2.50.1 From a91bfa67601c07ff9d31731fd2d624b47b0039f2 Mon Sep 17 00:00:00 2001 From: Steve French Date: Fri, 26 Jul 2024 18:44:16 -0500 Subject: [PATCH 09/16] cifs: update internal version number To 2.50 Signed-off-by: Steve French --- fs/smb/client/cifsfs.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/smb/client/cifsfs.h b/fs/smb/client/cifsfs.h index 62d5fee3e5eb..ca2bd204bcc5 100644 --- a/fs/smb/client/cifsfs.h +++ b/fs/smb/client/cifsfs.h @@ -147,6 +147,6 @@ extern const struct export_operations cifs_export_ops; #endif /* CONFIG_CIFS_NFSD_EXPORT */ /* when changing internal version - update following two lines at same time */ -#define SMB3_PRODUCT_BUILD 49 -#define CIFS_VERSION "2.49" +#define SMB3_PRODUCT_BUILD 50 +#define CIFS_VERSION "2.50" #endif /* _CIFSFS_H */ -- 2.50.1 From f2655ac2c06a15558e51ed6529de280e1553c86e Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 2 Aug 2024 08:46:15 -0700 Subject: [PATCH 10/16] clocksource: Fix brown-bag boolean thinko in cs_watchdog_read() The current "nretries > 1 || nretries >= max_retries" check in cs_watchdog_read() will always evaluate to true, and thus pr_warn(), if nretries is greater than 1. The intent is instead to never warn on the first try, but otherwise warn if the successful retry was the last retry. Therefore, change that "||" to "&&". Fixes: db3a34e17433 ("clocksource: Retry clock read if long delays detected") Reported-by: Borislav Petkov Signed-off-by: Paul E. McKenney Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240802154618.4149953-2-paulmck@kernel.org --- kernel/time/clocksource.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index d25ba49e313c..d0538a75f4c6 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -246,7 +246,7 @@ static enum wd_read_status cs_watchdog_read(struct clocksource *cs, u64 *csnow, wd_delay = cycles_to_nsec_safe(watchdog, *wdnow, wd_end); if (wd_delay <= WATCHDOG_MAX_SKEW) { - if (nretries > 1 || nretries >= max_retries) { + if (nretries > 1 && nretries >= max_retries) { pr_warn("timekeeping watchdog on CPU%d: %s retried %d times before success\n", smp_processor_id(), watchdog->name, nretries); } -- 2.50.1 From b6547e54864b998af21fdcaa0a88cf8e7efe641a Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 2 Aug 2024 18:12:06 -0700 Subject: [PATCH 11/16] runtime constants: deal with old decrepit linkers MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The runtime constants linker script depended on documented linker behavior [1]: "If an output section’s name is the same as the input section’s name and is representable as a C identifier, then the linker will automatically PROVIDE two symbols: __start_SECNAME and __stop_SECNAME, where SECNAME is the name of the section. These indicate the start address and end address of the output section respectively" to just automatically define the symbol names for the bounds of the runtime constant arrays. It turns out that this isn't actually something we can rely on, with old linkers not generating these automatic symbols. It looks to have been introduced in binutils-2.29 back in 2017, and we still support building with versions all the way back to binutils-2.25 (from 2015). And yes, Oleg actually seems to be using such ancient versions of binutils. So instead of depending on the implicit symbols from "section names match and are representable C identifiers", just do this all manually. It's not like it causes us any extra pain, we already have to do that for all the other sections that we use that often have special characters in them. Reported-and-tested-by: Oleg Nesterov Link: https://sourceware.org/binutils/docs/ld/Input-Section-Example.html [1] Link: https://lore.kernel.org/all/20240802114518.GA20924@redhat.com/ Signed-off-by: Linus Torvalds --- include/asm-generic/vmlinux.lds.h | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index ad6afc5c4918..1ae44793132a 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -911,13 +911,12 @@ #define CON_INITCALL \ BOUNDED_SECTION_POST_LABEL(.con_initcall.init, __con_initcall, _start, _end) -#define RUNTIME_NAME(t,x) runtime_##t##_##x +#define NAMED_SECTION(name) \ + . = ALIGN(8); \ + name : AT(ADDR(name) - LOAD_OFFSET) \ + { BOUNDED_SECTION_PRE_LABEL(name, name, __start_, __stop_) } -#define RUNTIME_CONST(t,x) \ - . = ALIGN(8); \ - RUNTIME_NAME(t,x) : AT(ADDR(RUNTIME_NAME(t,x)) - LOAD_OFFSET) { \ - *(RUNTIME_NAME(t,x)); \ - } +#define RUNTIME_CONST(t,x) NAMED_SECTION(runtime_##t##_##x) /* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */ #define KUNIT_TABLE() \ -- 2.50.1 From ff58838015c14a12cb8c003b9d6fc062b49e8d9e Mon Sep 17 00:00:00 2001 From: "Rob Herring (Arm)" Date: Tue, 30 Jul 2024 15:00:30 -0600 Subject: [PATCH 12/16] arm: dts: arm: versatile-ab: Fix duplicate clock node name Commit 04f08ef291d4 ("arm/arm64: dts: arm: Use generic clock and regulator nodenames") renamed nodes and created 2 "clock-24000000" nodes (at different paths). The kernel can't handle these duplicate names even though they are at different paths. Fix this by renaming one of the nodes to "clock-pclk". This name is aligned with other Arm boards (those didn't have a known frequency to use in the node name). Fixes: 04f08ef291d4 ("arm/arm64: dts: arm: Use generic clock and regulator nodenames") Reported-by: Guenter Roeck Signed-off-by: Rob Herring (Arm) Tested-by: Guenter Roeck Reviewed-by: Linus Walleij Tested-by: Linus Walleij Signed-off-by: Linus Torvalds --- arch/arm/boot/dts/arm/versatile-ab.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/boot/dts/arm/versatile-ab.dts b/arch/arm/boot/dts/arm/versatile-ab.dts index 6fe6b49f5d8e..635ab9268899 100644 --- a/arch/arm/boot/dts/arm/versatile-ab.dts +++ b/arch/arm/boot/dts/arm/versatile-ab.dts @@ -157,7 +157,7 @@ clocks = <&xtal24mhz>; }; - pclk: clock-24000000 { + pclk: clock-pclk { #clock-cells = <0>; compatible = "fixed-factor-clock"; clock-div = <1>; -- 2.50.1 From b88f55389ad27f05ed84af9e1026aa64dbfabc9a Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Sun, 4 Aug 2024 18:48:10 +0900 Subject: [PATCH 13/16] profiling: remove profile=sleep support The kernel sleep profile is no longer working due to a recursive locking bug introduced by commit 42a20f86dc19 ("sched: Add wrapper for get_wchan() to keep task blocked") Booting with the 'profile=sleep' kernel command line option added or executing # echo -n sleep > /sys/kernel/profiling after boot causes the system to lock up. Lockdep reports kthreadd/3 is trying to acquire lock: ffff93ac82e08d58 (&p->pi_lock){....}-{2:2}, at: get_wchan+0x32/0x70 but task is already holding lock: ffff93ac82e08d58 (&p->pi_lock){....}-{2:2}, at: try_to_wake_up+0x53/0x370 with the call trace being lock_acquire+0xc8/0x2f0 get_wchan+0x32/0x70 __update_stats_enqueue_sleeper+0x151/0x430 enqueue_entity+0x4b0/0x520 enqueue_task_fair+0x92/0x6b0 ttwu_do_activate+0x73/0x140 try_to_wake_up+0x213/0x370 swake_up_locked+0x20/0x50 complete+0x2f/0x40 kthread+0xfb/0x180 However, since nobody noticed this regression for more than two years, let's remove 'profile=sleep' support based on the assumption that nobody needs this functionality. Fixes: 42a20f86dc19 ("sched: Add wrapper for get_wchan() to keep task blocked") Cc: stable@vger.kernel.org # v5.16+ Signed-off-by: Tetsuo Handa Signed-off-by: Linus Torvalds --- Documentation/admin-guide/kernel-parameters.txt | 4 +--- include/linux/profile.h | 1 - kernel/profile.c | 11 +---------- kernel/sched/stats.c | 10 ---------- 4 files changed, 2 insertions(+), 24 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index f1384c7b59c9..09126bb8cc9f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4798,11 +4798,9 @@ profile= [KNL] Enable kernel profiling via /proc/profile Format: [,] - Param: : "schedule", "sleep", or "kvm" + Param: : "schedule" or "kvm" [defaults to kernel profiling] Param: "schedule" - profile schedule points. - Param: "sleep" - profile D-state sleeping (millisecs). - Requires CONFIG_SCHEDSTATS Param: "kvm" - profile VM exits. Param: - step/bucket size as a power of 2 for statistical time based profiling. diff --git a/include/linux/profile.h b/include/linux/profile.h index 2fb487f61d12..3f53cdb0c27c 100644 --- a/include/linux/profile.h +++ b/include/linux/profile.h @@ -10,7 +10,6 @@ #define CPU_PROFILING 1 #define SCHED_PROFILING 2 -#define SLEEP_PROFILING 3 #define KVM_PROFILING 4 struct proc_dir_entry; diff --git a/kernel/profile.c b/kernel/profile.c index ff68d3816182..1fcf1adcf4eb 100644 --- a/kernel/profile.c +++ b/kernel/profile.c @@ -50,20 +50,11 @@ EXPORT_SYMBOL_GPL(prof_on); int profile_setup(char *str) { static const char schedstr[] = "schedule"; - static const char sleepstr[] = "sleep"; static const char kvmstr[] = "kvm"; const char *select = NULL; int par; - if (!strncmp(str, sleepstr, strlen(sleepstr))) { -#ifdef CONFIG_SCHEDSTATS - force_schedstat_enabled(); - prof_on = SLEEP_PROFILING; - select = sleepstr; -#else - pr_warn("kernel sleep profiling requires CONFIG_SCHEDSTATS\n"); -#endif /* CONFIG_SCHEDSTATS */ - } else if (!strncmp(str, schedstr, strlen(schedstr))) { + if (!strncmp(str, schedstr, strlen(schedstr))) { prof_on = SCHED_PROFILING; select = schedstr; } else if (!strncmp(str, kvmstr, strlen(kvmstr))) { diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c index 78e48f5426ee..eb0cdcd4d921 100644 --- a/kernel/sched/stats.c +++ b/kernel/sched/stats.c @@ -92,16 +92,6 @@ void __update_stats_enqueue_sleeper(struct rq *rq, struct task_struct *p, trace_sched_stat_blocked(p, delta); - /* - * Blocking time is in units of nanosecs, so shift by - * 20 to get a milliseconds-range estimation of the - * amount of time that the task spent sleeping: - */ - if (unlikely(prof_on == SLEEP_PROFILING)) { - profile_hits(SLEEP_PROFILING, - (void *)get_wchan(p), - delta >> 20); - } account_scheduler_latency(p, delta >> 10, 0); } } -- 2.50.1 From de9c2c66ad8e787abec7c9d7eff4f8c3cdd28aed Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 4 Aug 2024 13:50:53 -0700 Subject: [PATCH 14/16] Linux 6.11-rc2 --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 8ad55d6e7b60..44c02a6f60a1 100644 --- a/Makefile +++ b/Makefile @@ -2,7 +2,7 @@ VERSION = 6 PATCHLEVEL = 11 SUBLEVEL = 0 -EXTRAVERSION = -rc1 +EXTRAVERSION = -rc2 NAME = Baby Opossum Posse # *DOCUMENTATION* -- 2.50.1 From 350afa8a1101f62ce31bc4ed6f69cf4b90ec4fa2 Mon Sep 17 00:00:00 2001 From: Ravi Bangoria Date: Thu, 8 Aug 2024 06:29:34 +0000 Subject: [PATCH 15/16] x86/split_lock: Move Split and Bus lock code to a dedicated file Bus Lock Detect functionality on AMD platforms works identical to Intel. Move split_lock and bus_lock specific code from intel.c to a dedicated file so that it can be compiled and supported on non-Intel platforms. Also, introduce CONFIG_X86_BUS_LOCK_DETECT, make it dependent on CONFIG_CPU_SUP_INTEL and add compilation dependency of the new bus_lock.c file on CONFIG_X86_BUS_LOCK_DETECT. Signed-off-by: Ravi Bangoria Signed-off-by: Thomas Gleixner Reviewed-by: Tom Lendacky Link: https://lore.kernel.org/all/20240808062937.1149-2-ravi.bangoria@amd.com --- arch/x86/Kconfig | 8 + arch/x86/include/asm/cpu.h | 11 +- arch/x86/kernel/cpu/Makefile | 2 + arch/x86/kernel/cpu/bus_lock.c | 406 +++++++++++++++++++++++++++++++++ arch/x86/kernel/cpu/intel.c | 406 --------------------------------- include/linux/sched.h | 2 +- kernel/fork.c | 2 +- 7 files changed, 427 insertions(+), 410 deletions(-) create mode 100644 arch/x86/kernel/cpu/bus_lock.c diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 007bab9f2a0e..9c4e69a1ae7a 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2426,6 +2426,14 @@ config CFI_AUTO_DEFAULT source "kernel/livepatch/Kconfig" +config X86_BUS_LOCK_DETECT + bool "Split Lock Detect and Bus Lock Detect support" + depends on CPU_SUP_INTEL + default y + help + Enable Split Lock Detect and Bus Lock Detect functionalities. + See for more information. + endmenu config CC_HAS_NAMED_AS diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index aa30fd8cad7f..86cf7952ee86 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -26,12 +26,13 @@ int mwait_usable(const struct cpuinfo_x86 *); unsigned int x86_family(unsigned int sig); unsigned int x86_model(unsigned int sig); unsigned int x86_stepping(unsigned int sig); -#ifdef CONFIG_CPU_SUP_INTEL +#ifdef CONFIG_X86_BUS_LOCK_DETECT extern void __init sld_setup(struct cpuinfo_x86 *c); extern bool handle_user_split_lock(struct pt_regs *regs, long error_code); extern bool handle_guest_split_lock(unsigned long ip); extern void handle_bus_lock(struct pt_regs *regs); -u8 get_this_hybrid_cpu_type(void); +void split_lock_init(void); +void bus_lock_init(void); #else static inline void __init sld_setup(struct cpuinfo_x86 *c) {} static inline bool handle_user_split_lock(struct pt_regs *regs, long error_code) @@ -45,7 +46,13 @@ static inline bool handle_guest_split_lock(unsigned long ip) } static inline void handle_bus_lock(struct pt_regs *regs) {} +static inline void split_lock_init(void) {} +static inline void bus_lock_init(void) {} +#endif +#ifdef CONFIG_CPU_SUP_INTEL +u8 get_this_hybrid_cpu_type(void); +#else static inline u8 get_this_hybrid_cpu_type(void) { return 0; diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index 5857a0f5d514..4efdf5c2efc8 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -59,6 +59,8 @@ obj-$(CONFIG_ACRN_GUEST) += acrn.o obj-$(CONFIG_DEBUG_FS) += debugfs.o +obj-$(CONFIG_X86_BUS_LOCK_DETECT) += bus_lock.o + quiet_cmd_mkcapflags = MKCAP $@ cmd_mkcapflags = $(CONFIG_SHELL) $(src)/mkcapflags.sh $@ $^ diff --git a/arch/x86/kernel/cpu/bus_lock.c b/arch/x86/kernel/cpu/bus_lock.c new file mode 100644 index 000000000000..704e9241b964 --- /dev/null +++ b/arch/x86/kernel/cpu/bus_lock.c @@ -0,0 +1,406 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define pr_fmt(fmt) "x86/split lock detection: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include + +enum split_lock_detect_state { + sld_off = 0, + sld_warn, + sld_fatal, + sld_ratelimit, +}; + +/* + * Default to sld_off because most systems do not support split lock detection. + * sld_state_setup() will switch this to sld_warn on systems that support + * split lock/bus lock detect, unless there is a command line override. + */ +static enum split_lock_detect_state sld_state __ro_after_init = sld_off; +static u64 msr_test_ctrl_cache __ro_after_init; + +/* + * With a name like MSR_TEST_CTL it should go without saying, but don't touch + * MSR_TEST_CTL unless the CPU is one of the whitelisted models. Writing it + * on CPUs that do not support SLD can cause fireworks, even when writing '0'. + */ +static bool cpu_model_supports_sld __ro_after_init; + +static const struct { + const char *option; + enum split_lock_detect_state state; +} sld_options[] __initconst = { + { "off", sld_off }, + { "warn", sld_warn }, + { "fatal", sld_fatal }, + { "ratelimit:", sld_ratelimit }, +}; + +static struct ratelimit_state bld_ratelimit; + +static unsigned int sysctl_sld_mitigate = 1; +static DEFINE_SEMAPHORE(buslock_sem, 1); + +#ifdef CONFIG_PROC_SYSCTL +static struct ctl_table sld_sysctls[] = { + { + .procname = "split_lock_mitigate", + .data = &sysctl_sld_mitigate, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, +}; + +static int __init sld_mitigate_sysctl_init(void) +{ + register_sysctl_init("kernel", sld_sysctls); + return 0; +} + +late_initcall(sld_mitigate_sysctl_init); +#endif + +static inline bool match_option(const char *arg, int arglen, const char *opt) +{ + int len = strlen(opt), ratelimit; + + if (strncmp(arg, opt, len)) + return false; + + /* + * Min ratelimit is 1 bus lock/sec. + * Max ratelimit is 1000 bus locks/sec. + */ + if (sscanf(arg, "ratelimit:%d", &ratelimit) == 1 && + ratelimit > 0 && ratelimit <= 1000) { + ratelimit_state_init(&bld_ratelimit, HZ, ratelimit); + ratelimit_set_flags(&bld_ratelimit, RATELIMIT_MSG_ON_RELEASE); + return true; + } + + return len == arglen; +} + +static bool split_lock_verify_msr(bool on) +{ + u64 ctrl, tmp; + + if (rdmsrl_safe(MSR_TEST_CTRL, &ctrl)) + return false; + if (on) + ctrl |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT; + else + ctrl &= ~MSR_TEST_CTRL_SPLIT_LOCK_DETECT; + if (wrmsrl_safe(MSR_TEST_CTRL, ctrl)) + return false; + rdmsrl(MSR_TEST_CTRL, tmp); + return ctrl == tmp; +} + +static void __init sld_state_setup(void) +{ + enum split_lock_detect_state state = sld_warn; + char arg[20]; + int i, ret; + + if (!boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) && + !boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) + return; + + ret = cmdline_find_option(boot_command_line, "split_lock_detect", + arg, sizeof(arg)); + if (ret >= 0) { + for (i = 0; i < ARRAY_SIZE(sld_options); i++) { + if (match_option(arg, ret, sld_options[i].option)) { + state = sld_options[i].state; + break; + } + } + } + sld_state = state; +} + +static void __init __split_lock_setup(void) +{ + if (!split_lock_verify_msr(false)) { + pr_info("MSR access failed: Disabled\n"); + return; + } + + rdmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache); + + if (!split_lock_verify_msr(true)) { + pr_info("MSR access failed: Disabled\n"); + return; + } + + /* Restore the MSR to its cached value. */ + wrmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache); + + setup_force_cpu_cap(X86_FEATURE_SPLIT_LOCK_DETECT); +} + +/* + * MSR_TEST_CTRL is per core, but we treat it like a per CPU MSR. Locking + * is not implemented as one thread could undo the setting of the other + * thread immediately after dropping the lock anyway. + */ +static void sld_update_msr(bool on) +{ + u64 test_ctrl_val = msr_test_ctrl_cache; + + if (on) + test_ctrl_val |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT; + + wrmsrl(MSR_TEST_CTRL, test_ctrl_val); +} + +void split_lock_init(void) +{ + /* + * #DB for bus lock handles ratelimit and #AC for split lock is + * disabled. + */ + if (sld_state == sld_ratelimit) { + split_lock_verify_msr(false); + return; + } + + if (cpu_model_supports_sld) + split_lock_verify_msr(sld_state != sld_off); +} + +static void __split_lock_reenable_unlock(struct work_struct *work) +{ + sld_update_msr(true); + up(&buslock_sem); +} + +static DECLARE_DELAYED_WORK(sl_reenable_unlock, __split_lock_reenable_unlock); + +static void __split_lock_reenable(struct work_struct *work) +{ + sld_update_msr(true); +} +static DECLARE_DELAYED_WORK(sl_reenable, __split_lock_reenable); + +/* + * If a CPU goes offline with pending delayed work to re-enable split lock + * detection then the delayed work will be executed on some other CPU. That + * handles releasing the buslock_sem, but because it executes on a + * different CPU probably won't re-enable split lock detection. This is a + * problem on HT systems since the sibling CPU on the same core may then be + * left running with split lock detection disabled. + * + * Unconditionally re-enable detection here. + */ +static int splitlock_cpu_offline(unsigned int cpu) +{ + sld_update_msr(true); + + return 0; +} + +static void split_lock_warn(unsigned long ip) +{ + struct delayed_work *work; + int cpu; + + if (!current->reported_split_lock) + pr_warn_ratelimited("#AC: %s/%d took a split_lock trap at address: 0x%lx\n", + current->comm, current->pid, ip); + current->reported_split_lock = 1; + + if (sysctl_sld_mitigate) { + /* + * misery factor #1: + * sleep 10ms before trying to execute split lock. + */ + if (msleep_interruptible(10) > 0) + return; + /* + * Misery factor #2: + * only allow one buslocked disabled core at a time. + */ + if (down_interruptible(&buslock_sem) == -EINTR) + return; + work = &sl_reenable_unlock; + } else { + work = &sl_reenable; + } + + cpu = get_cpu(); + schedule_delayed_work_on(cpu, work, 2); + + /* Disable split lock detection on this CPU to make progress */ + sld_update_msr(false); + put_cpu(); +} + +bool handle_guest_split_lock(unsigned long ip) +{ + if (sld_state == sld_warn) { + split_lock_warn(ip); + return true; + } + + pr_warn_once("#AC: %s/%d %s split_lock trap at address: 0x%lx\n", + current->comm, current->pid, + sld_state == sld_fatal ? "fatal" : "bogus", ip); + + current->thread.error_code = 0; + current->thread.trap_nr = X86_TRAP_AC; + force_sig_fault(SIGBUS, BUS_ADRALN, NULL); + return false; +} +EXPORT_SYMBOL_GPL(handle_guest_split_lock); + +void bus_lock_init(void) +{ + u64 val; + + if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) + return; + + rdmsrl(MSR_IA32_DEBUGCTLMSR, val); + + if ((boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) && + (sld_state == sld_warn || sld_state == sld_fatal)) || + sld_state == sld_off) { + /* + * Warn and fatal are handled by #AC for split lock if #AC for + * split lock is supported. + */ + val &= ~DEBUGCTLMSR_BUS_LOCK_DETECT; + } else { + val |= DEBUGCTLMSR_BUS_LOCK_DETECT; + } + + wrmsrl(MSR_IA32_DEBUGCTLMSR, val); +} + +bool handle_user_split_lock(struct pt_regs *regs, long error_code) +{ + if ((regs->flags & X86_EFLAGS_AC) || sld_state == sld_fatal) + return false; + split_lock_warn(regs->ip); + return true; +} + +void handle_bus_lock(struct pt_regs *regs) +{ + switch (sld_state) { + case sld_off: + break; + case sld_ratelimit: + /* Enforce no more than bld_ratelimit bus locks/sec. */ + while (!__ratelimit(&bld_ratelimit)) + msleep(20); + /* Warn on the bus lock. */ + fallthrough; + case sld_warn: + pr_warn_ratelimited("#DB: %s/%d took a bus_lock trap at address: 0x%lx\n", + current->comm, current->pid, regs->ip); + break; + case sld_fatal: + force_sig_fault(SIGBUS, BUS_ADRALN, NULL); + break; + } +} + +/* + * CPU models that are known to have the per-core split-lock detection + * feature even though they do not enumerate IA32_CORE_CAPABILITIES. + */ +static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = { + X86_MATCH_VFM(INTEL_ICELAKE_X, 0), + X86_MATCH_VFM(INTEL_ICELAKE_L, 0), + X86_MATCH_VFM(INTEL_ICELAKE_D, 0), + {} +}; + +static void __init split_lock_setup(struct cpuinfo_x86 *c) +{ + const struct x86_cpu_id *m; + u64 ia32_core_caps; + + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return; + + /* Check for CPUs that have support but do not enumerate it: */ + m = x86_match_cpu(split_lock_cpu_ids); + if (m) + goto supported; + + if (!cpu_has(c, X86_FEATURE_CORE_CAPABILITIES)) + return; + + /* + * Not all bits in MSR_IA32_CORE_CAPS are architectural, but + * MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT is. All CPUs that set + * it have split lock detection. + */ + rdmsrl(MSR_IA32_CORE_CAPS, ia32_core_caps); + if (ia32_core_caps & MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT) + goto supported; + + /* CPU is not in the model list and does not have the MSR bit: */ + return; + +supported: + cpu_model_supports_sld = true; + __split_lock_setup(); +} + +static void sld_state_show(void) +{ + if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT) && + !boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) + return; + + switch (sld_state) { + case sld_off: + pr_info("disabled\n"); + break; + case sld_warn: + if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) { + pr_info("#AC: crashing the kernel on kernel split_locks and warning on user-space split_locks\n"); + if (cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, + "x86/splitlock", NULL, splitlock_cpu_offline) < 0) + pr_warn("No splitlock CPU offline handler\n"); + } else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) { + pr_info("#DB: warning on user-space bus_locks\n"); + } + break; + case sld_fatal: + if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) { + pr_info("#AC: crashing the kernel on kernel split_locks and sending SIGBUS on user-space split_locks\n"); + } else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) { + pr_info("#DB: sending SIGBUS on user-space bus_locks%s\n", + boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) ? + " from non-WB" : ""); + } + break; + case sld_ratelimit: + if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) + pr_info("#DB: setting system wide bus lock rate limit to %u/sec\n", bld_ratelimit.burst); + break; + } +} + +void __init sld_setup(struct cpuinfo_x86 *c) +{ + split_lock_setup(c); + sld_state_setup(); + sld_state_show(); +} diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 08b95a35b5cb..8a483f4ad026 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -7,13 +7,9 @@ #include #include #include -#include #include #include #include -#include -#include -#include #include #include @@ -24,8 +20,6 @@ #include #include #include -#include -#include #include #include #include @@ -41,28 +35,6 @@ #include #endif -enum split_lock_detect_state { - sld_off = 0, - sld_warn, - sld_fatal, - sld_ratelimit, -}; - -/* - * Default to sld_off because most systems do not support split lock detection. - * sld_state_setup() will switch this to sld_warn on systems that support - * split lock/bus lock detect, unless there is a command line override. - */ -static enum split_lock_detect_state sld_state __ro_after_init = sld_off; -static u64 msr_test_ctrl_cache __ro_after_init; - -/* - * With a name like MSR_TEST_CTL it should go without saying, but don't touch - * MSR_TEST_CTL unless the CPU is one of the whitelisted models. Writing it - * on CPUs that do not support SLD can cause fireworks, even when writing '0'. - */ -static bool cpu_model_supports_sld __ro_after_init; - /* * Processors which have self-snooping capability can handle conflicting * memory type across CPUs by snooping its own cache. However, there exists @@ -547,9 +519,6 @@ static void init_intel_misc_features(struct cpuinfo_x86 *c) wrmsrl(MSR_MISC_FEATURES_ENABLES, msr); } -static void split_lock_init(void); -static void bus_lock_init(void); - static void init_intel(struct cpuinfo_x86 *c) { early_init_intel(c); @@ -907,381 +876,6 @@ static const struct cpu_dev intel_cpu_dev = { cpu_dev_register(intel_cpu_dev); -#undef pr_fmt -#define pr_fmt(fmt) "x86/split lock detection: " fmt - -static const struct { - const char *option; - enum split_lock_detect_state state; -} sld_options[] __initconst = { - { "off", sld_off }, - { "warn", sld_warn }, - { "fatal", sld_fatal }, - { "ratelimit:", sld_ratelimit }, -}; - -static struct ratelimit_state bld_ratelimit; - -static unsigned int sysctl_sld_mitigate = 1; -static DEFINE_SEMAPHORE(buslock_sem, 1); - -#ifdef CONFIG_PROC_SYSCTL -static struct ctl_table sld_sysctls[] = { - { - .procname = "split_lock_mitigate", - .data = &sysctl_sld_mitigate, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_douintvec_minmax, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, - }, -}; - -static int __init sld_mitigate_sysctl_init(void) -{ - register_sysctl_init("kernel", sld_sysctls); - return 0; -} - -late_initcall(sld_mitigate_sysctl_init); -#endif - -static inline bool match_option(const char *arg, int arglen, const char *opt) -{ - int len = strlen(opt), ratelimit; - - if (strncmp(arg, opt, len)) - return false; - - /* - * Min ratelimit is 1 bus lock/sec. - * Max ratelimit is 1000 bus locks/sec. - */ - if (sscanf(arg, "ratelimit:%d", &ratelimit) == 1 && - ratelimit > 0 && ratelimit <= 1000) { - ratelimit_state_init(&bld_ratelimit, HZ, ratelimit); - ratelimit_set_flags(&bld_ratelimit, RATELIMIT_MSG_ON_RELEASE); - return true; - } - - return len == arglen; -} - -static bool split_lock_verify_msr(bool on) -{ - u64 ctrl, tmp; - - if (rdmsrl_safe(MSR_TEST_CTRL, &ctrl)) - return false; - if (on) - ctrl |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT; - else - ctrl &= ~MSR_TEST_CTRL_SPLIT_LOCK_DETECT; - if (wrmsrl_safe(MSR_TEST_CTRL, ctrl)) - return false; - rdmsrl(MSR_TEST_CTRL, tmp); - return ctrl == tmp; -} - -static void __init sld_state_setup(void) -{ - enum split_lock_detect_state state = sld_warn; - char arg[20]; - int i, ret; - - if (!boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) && - !boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) - return; - - ret = cmdline_find_option(boot_command_line, "split_lock_detect", - arg, sizeof(arg)); - if (ret >= 0) { - for (i = 0; i < ARRAY_SIZE(sld_options); i++) { - if (match_option(arg, ret, sld_options[i].option)) { - state = sld_options[i].state; - break; - } - } - } - sld_state = state; -} - -static void __init __split_lock_setup(void) -{ - if (!split_lock_verify_msr(false)) { - pr_info("MSR access failed: Disabled\n"); - return; - } - - rdmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache); - - if (!split_lock_verify_msr(true)) { - pr_info("MSR access failed: Disabled\n"); - return; - } - - /* Restore the MSR to its cached value. */ - wrmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache); - - setup_force_cpu_cap(X86_FEATURE_SPLIT_LOCK_DETECT); -} - -/* - * MSR_TEST_CTRL is per core, but we treat it like a per CPU MSR. Locking - * is not implemented as one thread could undo the setting of the other - * thread immediately after dropping the lock anyway. - */ -static void sld_update_msr(bool on) -{ - u64 test_ctrl_val = msr_test_ctrl_cache; - - if (on) - test_ctrl_val |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT; - - wrmsrl(MSR_TEST_CTRL, test_ctrl_val); -} - -static void split_lock_init(void) -{ - /* - * #DB for bus lock handles ratelimit and #AC for split lock is - * disabled. - */ - if (sld_state == sld_ratelimit) { - split_lock_verify_msr(false); - return; - } - - if (cpu_model_supports_sld) - split_lock_verify_msr(sld_state != sld_off); -} - -static void __split_lock_reenable_unlock(struct work_struct *work) -{ - sld_update_msr(true); - up(&buslock_sem); -} - -static DECLARE_DELAYED_WORK(sl_reenable_unlock, __split_lock_reenable_unlock); - -static void __split_lock_reenable(struct work_struct *work) -{ - sld_update_msr(true); -} -static DECLARE_DELAYED_WORK(sl_reenable, __split_lock_reenable); - -/* - * If a CPU goes offline with pending delayed work to re-enable split lock - * detection then the delayed work will be executed on some other CPU. That - * handles releasing the buslock_sem, but because it executes on a - * different CPU probably won't re-enable split lock detection. This is a - * problem on HT systems since the sibling CPU on the same core may then be - * left running with split lock detection disabled. - * - * Unconditionally re-enable detection here. - */ -static int splitlock_cpu_offline(unsigned int cpu) -{ - sld_update_msr(true); - - return 0; -} - -static void split_lock_warn(unsigned long ip) -{ - struct delayed_work *work; - int cpu; - - if (!current->reported_split_lock) - pr_warn_ratelimited("#AC: %s/%d took a split_lock trap at address: 0x%lx\n", - current->comm, current->pid, ip); - current->reported_split_lock = 1; - - if (sysctl_sld_mitigate) { - /* - * misery factor #1: - * sleep 10ms before trying to execute split lock. - */ - if (msleep_interruptible(10) > 0) - return; - /* - * Misery factor #2: - * only allow one buslocked disabled core at a time. - */ - if (down_interruptible(&buslock_sem) == -EINTR) - return; - work = &sl_reenable_unlock; - } else { - work = &sl_reenable; - } - - cpu = get_cpu(); - schedule_delayed_work_on(cpu, work, 2); - - /* Disable split lock detection on this CPU to make progress */ - sld_update_msr(false); - put_cpu(); -} - -bool handle_guest_split_lock(unsigned long ip) -{ - if (sld_state == sld_warn) { - split_lock_warn(ip); - return true; - } - - pr_warn_once("#AC: %s/%d %s split_lock trap at address: 0x%lx\n", - current->comm, current->pid, - sld_state == sld_fatal ? "fatal" : "bogus", ip); - - current->thread.error_code = 0; - current->thread.trap_nr = X86_TRAP_AC; - force_sig_fault(SIGBUS, BUS_ADRALN, NULL); - return false; -} -EXPORT_SYMBOL_GPL(handle_guest_split_lock); - -static void bus_lock_init(void) -{ - u64 val; - - if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) - return; - - rdmsrl(MSR_IA32_DEBUGCTLMSR, val); - - if ((boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) && - (sld_state == sld_warn || sld_state == sld_fatal)) || - sld_state == sld_off) { - /* - * Warn and fatal are handled by #AC for split lock if #AC for - * split lock is supported. - */ - val &= ~DEBUGCTLMSR_BUS_LOCK_DETECT; - } else { - val |= DEBUGCTLMSR_BUS_LOCK_DETECT; - } - - wrmsrl(MSR_IA32_DEBUGCTLMSR, val); -} - -bool handle_user_split_lock(struct pt_regs *regs, long error_code) -{ - if ((regs->flags & X86_EFLAGS_AC) || sld_state == sld_fatal) - return false; - split_lock_warn(regs->ip); - return true; -} - -void handle_bus_lock(struct pt_regs *regs) -{ - switch (sld_state) { - case sld_off: - break; - case sld_ratelimit: - /* Enforce no more than bld_ratelimit bus locks/sec. */ - while (!__ratelimit(&bld_ratelimit)) - msleep(20); - /* Warn on the bus lock. */ - fallthrough; - case sld_warn: - pr_warn_ratelimited("#DB: %s/%d took a bus_lock trap at address: 0x%lx\n", - current->comm, current->pid, regs->ip); - break; - case sld_fatal: - force_sig_fault(SIGBUS, BUS_ADRALN, NULL); - break; - } -} - -/* - * CPU models that are known to have the per-core split-lock detection - * feature even though they do not enumerate IA32_CORE_CAPABILITIES. - */ -static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = { - X86_MATCH_VFM(INTEL_ICELAKE_X, 0), - X86_MATCH_VFM(INTEL_ICELAKE_L, 0), - X86_MATCH_VFM(INTEL_ICELAKE_D, 0), - {} -}; - -static void __init split_lock_setup(struct cpuinfo_x86 *c) -{ - const struct x86_cpu_id *m; - u64 ia32_core_caps; - - if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) - return; - - /* Check for CPUs that have support but do not enumerate it: */ - m = x86_match_cpu(split_lock_cpu_ids); - if (m) - goto supported; - - if (!cpu_has(c, X86_FEATURE_CORE_CAPABILITIES)) - return; - - /* - * Not all bits in MSR_IA32_CORE_CAPS are architectural, but - * MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT is. All CPUs that set - * it have split lock detection. - */ - rdmsrl(MSR_IA32_CORE_CAPS, ia32_core_caps); - if (ia32_core_caps & MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT) - goto supported; - - /* CPU is not in the model list and does not have the MSR bit: */ - return; - -supported: - cpu_model_supports_sld = true; - __split_lock_setup(); -} - -static void sld_state_show(void) -{ - if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT) && - !boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) - return; - - switch (sld_state) { - case sld_off: - pr_info("disabled\n"); - break; - case sld_warn: - if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) { - pr_info("#AC: crashing the kernel on kernel split_locks and warning on user-space split_locks\n"); - if (cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, - "x86/splitlock", NULL, splitlock_cpu_offline) < 0) - pr_warn("No splitlock CPU offline handler\n"); - } else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) { - pr_info("#DB: warning on user-space bus_locks\n"); - } - break; - case sld_fatal: - if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) { - pr_info("#AC: crashing the kernel on kernel split_locks and sending SIGBUS on user-space split_locks\n"); - } else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) { - pr_info("#DB: sending SIGBUS on user-space bus_locks%s\n", - boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) ? - " from non-WB" : ""); - } - break; - case sld_ratelimit: - if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) - pr_info("#DB: setting system wide bus lock rate limit to %u/sec\n", bld_ratelimit.burst); - break; - } -} - -void __init sld_setup(struct cpuinfo_x86 *c) -{ - split_lock_setup(c); - sld_state_setup(); - sld_state_show(); -} - #define X86_HYBRID_CPU_TYPE_ID_SHIFT 24 /** diff --git a/include/linux/sched.h b/include/linux/sched.h index f8d150343d42..d606b2a1de99 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -976,7 +976,7 @@ struct task_struct { #ifdef CONFIG_ARCH_HAS_CPU_PASID unsigned pasid_activated:1; #endif -#ifdef CONFIG_CPU_SUP_INTEL +#ifdef CONFIG_X86_BUS_LOCK_DETECT unsigned reported_split_lock:1; #endif #ifdef CONFIG_TASK_DELAY_ACCT diff --git a/kernel/fork.c b/kernel/fork.c index cc760491f201..7f1f3dc6f310 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1182,7 +1182,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) tsk->active_memcg = NULL; #endif -#ifdef CONFIG_CPU_SUP_INTEL +#ifdef CONFIG_X86_BUS_LOCK_DETECT tsk->reported_split_lock = 0; #endif -- 2.50.1 From 408eb7417a92c5354c7be34f7425b305dfe30ad9 Mon Sep 17 00:00:00 2001 From: Ravi Bangoria Date: Thu, 8 Aug 2024 06:29:35 +0000 Subject: [PATCH 16/16] x86/bus_lock: Add support for AMD Add Bus Lock Detect (called Bus Lock Trap in AMD docs) support for AMD platforms. Bus Lock Detect is enumerated with CPUID Fn0000_0007_ECX_x0 bit [24 / BUSLOCKTRAP]. It can be enabled through MSR_IA32_DEBUGCTLMSR. When enabled, hardware clears DR6[11] and raises a #DB exception on occurrence of Bus Lock if CPL > 0. More detail about the feature can be found in AMD APM[1]. [1]: AMD64 Architecture Programmer's Manual Pub. 40332, Rev. 4.07 - June 2023, Vol 2, 13.1.3.6 Bus Lock Trap https://bugzilla.kernel.org/attachment.cgi?id=304653 Signed-off-by: Ravi Bangoria Signed-off-by: Thomas Gleixner Reviewed-by: Tom Lendacky Link: https://lore.kernel.org/all/20240808062937.1149-3-ravi.bangoria@amd.com --- Documentation/arch/x86/buslock.rst | 3 ++- arch/x86/Kconfig | 2 +- arch/x86/kernel/cpu/common.c | 2 ++ arch/x86/kernel/cpu/intel.c | 1 - 4 files changed, 5 insertions(+), 3 deletions(-) diff --git a/Documentation/arch/x86/buslock.rst b/Documentation/arch/x86/buslock.rst index 4c5a4822eeb7..31f1bfdff16f 100644 --- a/Documentation/arch/x86/buslock.rst +++ b/Documentation/arch/x86/buslock.rst @@ -26,7 +26,8 @@ Detection ========= Intel processors may support either or both of the following hardware -mechanisms to detect split locks and bus locks. +mechanisms to detect split locks and bus locks. Some AMD processors also +support bus lock detect. #AC exception for split lock detection -------------------------------------- diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 9c4e69a1ae7a..e3d53fc7419a 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2428,7 +2428,7 @@ source "kernel/livepatch/Kconfig" config X86_BUS_LOCK_DETECT bool "Split Lock Detect and Bus Lock Detect support" - depends on CPU_SUP_INTEL + depends on CPU_SUP_INTEL || CPU_SUP_AMD default y help Enable Split Lock Detect and Bus Lock Detect functionalities. diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index d4e539d4e158..a37670e1ab4d 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1832,6 +1832,8 @@ static void identify_cpu(struct cpuinfo_x86 *c) if (this_cpu->c_init) this_cpu->c_init(c); + bus_lock_init(); + /* Disable the PN if appropriate */ squash_the_stupid_serial_number(c); diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 8a483f4ad026..799f18545c6e 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -610,7 +610,6 @@ static void init_intel(struct cpuinfo_x86 *c) init_intel_misc_features(c); split_lock_init(); - bus_lock_init(); intel_init_thermal(c); } -- 2.50.1