kernel/linux.git/init/Kconfig, branch v6.6.39

rust: make mutually exclusive with CFI_CLANG

2024-05-02T14:32:42+00:00

commit 8933cf4651e02853ca679be7b2d978dfcdcc5e0c upstream. On RISC-V and arm64, and presumably x86, if CFI_CLANG is enabled, loading a rust module will trigger a kernel panic. Support for sanitisers, including kcfi (CFI_CLANG), is in the works, but for now they're nightly-only options in rustc. Make RUST depend on !CFI_CLANG to prevent configuring a kernel without symmetrical support for kfi. [ Matthew Maurer writes [1]: This patch is fine by me - the last patch needed for KCFI to be functional in Rust just landed upstream last night, so we should revisit this (in the form of enabling it) once we move to `rustc-1.79.0` or later. Ramon de C Valle also gave feedback [2] on the status of KCFI for Rust and created a tracking issue [3] in upstream Rust. - Miguel ] Fixes: 2f7ab1267dc9 ("Kbuild: add Rust support") Cc: stable@vger.kernel.org Signed-off-by: Conor Dooley Acked-by: Nathan Chancellor Link: https://lore.kernel.org/rust-for-linux/CAGSQo024u1gHJgzsO38Xg3c4or+JupoPABQx_+0BLEpPg0cOEA@mail.gmail.com/ [1] Link: https://lore.kernel.org/rust-for-linux/CAOcBZOS2kPyH0Dm7Fuh4GC3=v7nZhyzBj_-dKu3PfAnrHZvaxg@mail.gmail.com/ [2] Link: https://github.com/rust-lang/rust/issues/123479 [3] Link: https://lore.kernel.org/r/20240404-providing-emporium-e652e359c711@spud [ Added feedback from the list, links, and used Cc for the tag. ] Signed-off-by: Miguel Ojeda Signed-off-by: Greg Kroah-Hartman

rust: don't select CONSTRUCTORS

2024-05-02T14:32:42+00:00

commit 7d49f53af4b988b188d3932deac2c9c80fd7d9ce upstream. This was originally part of commit 4b9a68f2e59a0 ("rust: add support for static synchronisation primitives") from the old Rust branch, which used module constructors to initialize globals containing various synchronisation primitives with pin-init. That commit has never been upstreamed, but the `select CONSTRUCTORS` statement ended up being included in the patch that initially added Rust support to the Linux Kernel. We are not using module constructors, so let's remove the select. Signed-off-by: Alice Ryhl Reviewed-by: Benno Lossin Cc: stable@vger.kernel.org Fixes: 2f7ab1267dc9 ("Kbuild: add Rust support") Link: https://lore.kernel.org/r/20240308-constructors-v1-1-4c811342391c@google.com Signed-off-by: Miguel Ojeda Signed-off-by: Greg Kroah-Hartman

init/Kconfig: lower GCC version check for -Warray-bounds

2024-04-03T13:28:41+00:00

commit 3e00f5802fabf2f504070a591b14b648523ede13 upstream. We continue to see false positives from -Warray-bounds even in GCC 10, which is getting reported in a few places[1] still: security/security.c:811:2: warning: `memcpy' offset 32 is out of the bounds [0, 0] [-Warray-bounds] Lower the GCC version check from 11 to 10. Link: https://lkml.kernel.org/r/20240223170824.work.768-kees@kernel.org Reported-by: Lu Yao Closes: https://lore.kernel.org/lkml/20240117014541.8887-1-yaolu@kylinos.cn/ Link: https://lore.kernel.org/linux-next/65d84438.620a0220.7d171.81a7@mx.google.com [1] Signed-off-by: Kees Cook Reviewed-by: Paul Moore Cc: Ard Biesheuvel Cc: Christophe Leroy Cc: Greg Kroah-Hartman Cc: "Gustavo A. R. Silva" Cc: Johannes Weiner Cc: Marc Aurèle La France Cc: Masahiro Yamada Cc: Nathan Chancellor Cc: Nhat Pham Cc: Petr Mladek Cc: Randy Dunlap Cc: Suren Baghdasaryan Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

update workarounds for gcc "asm goto" issue

2024-02-23T08:24:47+00:00

commit 68fb3ca0e408e00db1c3f8fccdfa19e274c033be upstream. In commit 4356e9f841f7 ("work around gcc bugs with 'asm goto' with outputs") I did the gcc workaround unconditionally, because the cause of the bad code generation wasn't entirely clear. In the meantime, Jakub Jelinek debugged the issue, and has come up with a fix in gcc [2], which also got backported to the still maintained branches of gcc-11, gcc-12 and gcc-13. Note that while the fix technically wasn't in the original gcc-14 branch, Jakub says: "while it is true that no GCC 14 snapshots until today (or whenever the fix will be committed) have the fix, for GCC trunk it is up to the distros to use the latest snapshot if they use it at all and would allow better testing of the kernel code without the workaround, so that if there are other issues they won't be discovered years later. Most userland code doesn't actually use asm goto with outputs..." so we will consider gcc-14 to be fixed - if somebody is using gcc snapshots of the gcc-14 before the fix, they should upgrade. Note that while the bug goes back to gcc-11, in practice other gcc changes seem to have effectively hidden it since gcc-12.1 as per a bisect by Jakub. So even a gcc-14 snapshot without the fix likely doesn't show actual problems. Also, make the default 'asm_goto_output()' macro mark the asm as volatile by hand, because of an unrelated gcc issue [1] where it doesn't match the documented behavior ("asm goto is always volatile"). Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103979 [1] Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113921 [2] Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/ Requested-by: Jakub Jelinek Cc: Uros Bizjak Cc: Nick Desaulniers Cc: Sean Christopherson Cc: Andrew Pinski Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Merge tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2023-08-29T21:53:51+00:00

Pull non-MM updates from Andrew Morton: - An extensive rework of kexec and crash Kconfig from Eric DeVolder ("refactor Kconfig to consolidate KEXEC and CRASH options") - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a couple of macros to args.h") - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper commands") - vsprintf inclusion rationalization from Andy Shevchenko ("lib/vsprintf: Rework header inclusions") - Switch the handling of kdump from a udev scheme to in-kernel handling, by Eric DeVolder ("crash: Kernel handling of CPU and memory hot un/plug") - Many singleton patches to various parts of the tree * tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (81 commits) document while_each_thread(), change first_tid() to use for_each_thread() drivers/char/mem.c: shrink character device's devlist[] array x86/crash: optimize CPU changes crash: change crash_prepare_elf64_headers() to for_each_possible_cpu() crash: hotplug support for kexec_load() x86/crash: add x86 crash hotplug support crash: memory and CPU hotplug sysfs attributes kexec: exclude elfcorehdr from the segment digest crash: add generic infrastructure for crash hotplug support crash: move a few code bits to setup support of crash hotplug kstrtox: consistently use _tolower() kill do_each_thread() nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse scripts/bloat-o-meter: count weak symbol sizes treewide: drop CONFIG_EMBEDDED lockdep: fix static memory detection even more lib/vsprintf: declare no_hash_pointers in sprintf.h lib/vsprintf: split out sprintf() and friends kernel/fork: stop playing lockless games for exe_file replacement adfs: delete unused "union adfs_dirtail" definition ...

treewide: drop CONFIG_EMBEDDED

2023-08-21T20:46:25+00:00

There is only one Kconfig user of CONFIG_EMBEDDED and it can be switched to EXPERT or "if !ARCH_MULTIPLATFORM" (suggested by Arnd). Link: https://lkml.kernel.org/r/20230816055010.31534-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap Acked-by: Geert Uytterhoeven Acked-by: Arnd Bergmann Acked-by: Palmer Dabbelt [RISC-V] Acked-by: Greg Ungerer Acked-by: Jason A. Donenfeld Acked-by: Michael Ellerman [powerpc] Cc: Russell King Cc: Vineet Gupta Cc: Brian Cain Cc: Michal Simek Cc: Thomas Bogendoerfer Cc: Dinh Nguyen Cc: Jonas Bonn Cc: Stefan Kristiansson Cc: Stafford Horne Cc: Nicholas Piggin Cc: Christophe Leroy Cc: Paul Walmsley Cc: Albert Ou Cc: Yoshinori Sato Cc: Rich Felker Cc: John Paul Adrian Glaubitz Cc: Max Filippov Cc: Josh Triplett Cc: Masahiro Yamada Signed-off-by: Andrew Morton

kexec: consolidate kexec and crash options into kernel/Kconfig.kexec

2023-08-18T17:18:51+00:00

Patch series "refactor Kconfig to consolidate KEXEC and CRASH options", v6. The Kconfig is refactored to consolidate KEXEC and CRASH options from various arch//Kconfig files into new file kernel/Kconfig.kexec. The Kconfig.kexec is now a submenu titled "Kexec and crash features" located under "General Setup". The following options are impacted: - KEXEC - KEXEC_FILE - KEXEC_SIG - KEXEC_SIG_FORCE - KEXEC_IMAGE_VERIFY_SIG - KEXEC_BZIMAGE_VERIFY_SIG - KEXEC_JUMP - CRASH_DUMP Over time, these options have been copied between Kconfig files and are very similar to one another, but with slight differences. The following architectures are impacted by the refactor (because of use of one or more KEXEC/CRASH options): - arm - arm64 - ia64 - loongarch - m68k - mips - parisc - powerpc - riscv - s390 - sh - x86 More information: In the patch series "crash: Kernel handling of CPU and memory hot un/plug" https://lore.kernel.org/lkml/20230503224145.7405-1-eric.devolder@oracle.com/ the new kernel feature introduces the config option CRASH_HOTPLUG. In reviewing, Thomas Gleixner requested that the new config option not be placed in x86 Kconfig. Rather the option needs a generic/common home. To Thomas' point, the KEXEC and CRASH options have largely been duplicated in the various arch//Kconfig files, with minor differences. This kind of proliferation is to be avoid/stopped. https://lore.kernel.org/lkml/875y91yv63.ffs@tglx/ To that end, I have refactored the arch Kconfigs so as to consolidate the various KEXEC and CRASH options. Generally speaking, this work has the following themes: - KEXEC and CRASH options are moved into new file kernel/Kconfig.kexec - These items from arch/Kconfig: CRASH_CORE KEXEC_CORE KEXEC_ELF HAVE_IMA_KEXEC - These items from arch/x86/Kconfig form the common options: KEXEC KEXEC_FILE KEXEC_SIG KEXEC_SIG_FORCE KEXEC_BZIMAGE_VERIFY_SIG KEXEC_JUMP CRASH_DUMP - These items from arch/arm64/Kconfig form the common options: KEXEC_IMAGE_VERIFY_SIG - The crash hotplug series appends CRASH_HOTPLUG to Kconfig.kexec - The Kconfig.kexec is now a submenu titled "Kexec and crash features" and is now listed in "General Setup" submenu from init/Kconfig. - To control the common options, each has a new ARCH_SUPPORTS_

sched/psi: Select KERNFS as needed

2023-08-02T14:19:25+00:00

Users of KERNFS should select it to enforce its being built, so do this to prevent a build error. In file included from ../kernel/sched/build_utility.c:97: ../kernel/sched/psi.c: In function 'psi_trigger_poll': ../kernel/sched/psi.c:1479:17: error: implicit declaration of function 'kernfs_generic_poll' [-Werror=implicit-function-declaration] 1479 | kernfs_generic_poll(t->of, wait); Fixes: aff037078eca ("sched/psi: use kernfs polling functions for PSI trigger polling") Reported-by: kernel test robot Signed-off-by: Randy Dunlap Signed-off-by: Peter Zijlstra (Intel) Acked-by: Suren Baghdasaryan Link: lore.kernel.org/r/202307310732.r65EQFY0-lkp@intel.com

cachestat: implement cachestat syscall

2023-06-09T23:25:16+00:00

There is currently no good way to query the page cache state of large file sets and directory trees. There is mincore(), but it scales poorly: the kernel writes out a lot of bitmap data that userspace has to aggregate, when the user really doesn not care about per-page information in that case. The user also needs to mmap and unmap each file as it goes along, which can be quite slow as well. Some use cases where this information could come in handy: * Allowing database to decide whether to perform an index scan or direct table queries based on the in-memory cache state of the index. * Visibility into the writeback algorithm, for performance issues diagnostic. * Workload-aware writeback pacing: estimating IO fulfilled by page cache (and IO to be done) within a range of a file, allowing for more frequent syncing when and where there is IO capacity, and batching when there is not. * Computing memory usage of large files/directory trees, analogous to the du tool for disk usage. More information about these use cases could be found in the following thread: https://lore.kernel.org/lkml/20230315170934.GA97793@cmpxchg.org/ This patch implements a new syscall that queries cache state of a file and summarizes the number of cached pages, number of dirty pages, number of pages marked for writeback, number of (recently) evicted pages, etc. in a given range. Currently, the syscall is only wired in for x86 architecture. NAME cachestat - query the page cache statistics of a file. SYNOPSIS #include struct cachestat_range { __u64 off; __u64 len; }; struct cachestat { __u64 nr_cache; __u64 nr_dirty; __u64 nr_writeback; __u64 nr_evicted; __u64 nr_recently_evicted; }; int cachestat(unsigned int fd, struct cachestat_range *cstat_range, struct cachestat *cstat, unsigned int flags); DESCRIPTION cachestat() queries the number of cached pages, number of dirty pages, number of pages marked for writeback, number of evicted pages, number of recently evicted pages, in the bytes range given by `off` and `len`. An evicted page is a page that is previously in the page cache but has been evicted since. A page is recently evicted if its last eviction was recent enough that its reentry to the cache would indicate that it is actively being used by the system, and that there is memory pressure on the system. These values are returned in a cachestat struct, whose address is given by the `cstat` argument. The `off` and `len` arguments must be non-negative integers. If `len` > 0, the queried range is [`off`, `off` + `len`]. If `len` == 0, we will query in the range from `off` to the end of the file. The `flags` argument is unused for now, but is included for future extensibility. User should pass 0 (i.e no flag specified). Currently, hugetlbfs is not supported. Because the status of a page can change after cachestat() checks it but before it returns to the application, the returned values may contain stale information. RETURN VALUE On success, cachestat returns 0. On error, -1 is returned, and errno is set to indicate the error. ERRORS EFAULT cstat or cstat_args points to an invalid address. EINVAL invalid flags. EBADF invalid file descriptor. EOPNOTSUPP file descriptor is of a hugetlbfs file [nphamcs@gmail.com: replace rounddown logic with the existing helper] Link: https://lkml.kernel.org/r/20230504022044.3675469-1-nphamcs@gmail.com Link: https://lkml.kernel.org/r/20230503013608.2431726-3-nphamcs@gmail.com Signed-off-by: Nhat Pham Acked-by: Johannes Weiner Cc: Brian Foster Cc: Matthew Wilcox (Oracle) Cc: Michael Kerrisk Signed-off-by: Andrew Morton

Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2023-04-27T18:53:57+00:00

Pull driver core updates from Greg KH: "Here is the large set of driver core changes for 6.4-rc1. Once again, a busy development cycle, with lots of changes happening in the driver core in the quest to be able to move "struct bus" and "struct class" into read-only memory, a task now complete with these changes. This will make the future rust interactions with the driver core more "provably correct" as well as providing more obvious lifetime rules for all busses and classes in the kernel. The changes required for this did touch many individual classes and busses as many callbacks were changed to take const * parameters instead. All of these changes have been submitted to the various subsystem maintainers, giving them plenty of time to review, and most of them actually did so. Other than those changes, included in here are a small set of other things: - kobject logging improvements - cacheinfo improvements and updates - obligatory fw_devlink updates and fixes - documentation updates - device property cleanups and const * changes - firwmare loader dependency fixes. All of these have been in linux-next for a while with no reported problems" * tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits) device property: make device_property functions take const device * driver core: update comments in device_rename() driver core: Don't require dynamic_debug for initcall_debug probe timing firmware_loader: rework crypto dependencies firmware_loader: Strip off \n from customized path zram: fix up permission for the hot_add sysfs file cacheinfo: Add use_arch[|_cache]_info field/function arch_topology: Remove early cacheinfo error message if -ENOENT cacheinfo: Check cache properties are present in DT cacheinfo: Check sib_leaf in cache_leaves_are_shared() cacheinfo: Allow early level detection when DT/ACPI info is missing/broken cacheinfo: Add arm64 early level initializer implementation cacheinfo: Add arch specific early level initializer tty: make tty_class a static const structure driver core: class: remove struct class_interface * from callbacks driver core: class: mark the struct class in struct class_interface constant driver core: class: make class_register() take a const * driver core: class: mark class_release() as taking a const * driver core: remove incorrect comment for device_create* MIPS: vpe-cmp: remove module owner pointer from struct class usage. ...