summaryrefslogtreecommitdiff
path: root/arch/m68k/kernel
AgeCommit message (Collapse)AuthorFilesLines
2024-09-24Merge tag 'm68knommu-for-v6.12' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu Pull m68knommu fixlet from Greg Ungerer: "Only a single change, cleaning up white space in debug message" * tag 'm68knommu-for-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68k: remove trailing space after \n newline
2024-09-09m68k: remove trailing space after \n newlineColin Ian King1-1/+1
There is a extraneous space after a newline in a pr_debug message. Remove it. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2024-08-26m68k: Fix kernel_clone_args.flags in m68k_clone()Finn Thain1-1/+1
Stan Johnson recently reported a failure from the 'dump' command: DUMP: Date of this level 0 dump: Fri Aug 9 23:37:15 2024 DUMP: Dumping /dev/sda (an unlisted file system) to /dev/null DUMP: Label: none DUMP: Writing 10 Kilobyte records DUMP: mapping (Pass I) [regular files] DUMP: mapping (Pass II) [directories] DUMP: estimated 3595695 blocks. DUMP: Context save fork fails in parent 671 The dump program uses the clone syscall with the CLONE_IO flag, that is, flags == 0x80000000. When that value is promoted from long int to u64 by m68k_clone(), it undergoes sign-extension. The new value includes CLONE_INTO_CGROUP so the validation in cgroup_css_set_fork() fails and the syscall returns -EBADF. Avoid sign-extension by casting to u32. Reported-by: Stan Johnson <userm57@yahoo.com> Closes: https://lists.debian.org/debian-68k/2024/08/msg00000.html Fixes: 6aabc1facdb2 ("m68k: Implement copy_thread_tls()") Signed-off-by: Finn Thain <fthain@linux-m68k.org> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/3463f1e5d4e95468dc9f3368f2b78ffa7b72199b.1723335149.git.fthain@linux-m68k.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-05-24mseal: wire up mseal syscallJeff Xu1-0/+1
Patch series "Introduce mseal", v10. This patchset proposes a new mseal() syscall for the Linux kernel. In a nutshell, mseal() protects the VMAs of a given virtual memory range against modifications, such as changes to their permission bits. Modern CPUs support memory permissions, such as the read/write (RW) and no-execute (NX) bits. Linux has supported NX since the release of kernel version 2.6.8 in August 2004 [1]. The memory permission feature improves the security stance on memory corruption bugs, as an attacker cannot simply write to arbitrary memory and point the code to it. The memory must be marked with the X bit, or else an exception will occur. Internally, the kernel maintains the memory permissions in a data structure called VMA (vm_area_struct). mseal() additionally protects the VMA itself against modifications of the selected seal type. Memory sealing is useful to mitigate memory corruption issues where a corrupted pointer is passed to a memory management system. For example, such an attacker primitive can break control-flow integrity guarantees since read-only memory that is supposed to be trusted can become writable or .text pages can get remapped. Memory sealing can automatically be applied by the runtime loader to seal .text and .rodata pages and applications can additionally seal security critical data at runtime. A similar feature already exists in the XNU kernel with the VM_FLAGS_PERMANENT [3] flag and on OpenBSD with the mimmutable syscall [4]. Also, Chrome wants to adopt this feature for their CFI work [2] and this patchset has been designed to be compatible with the Chrome use case. Two system calls are involved in sealing the map: mmap() and mseal(). The new mseal() is an syscall on 64 bit CPU, and with following signature: int mseal(void addr, size_t len, unsigned long flags) addr/len: memory range. flags: reserved. mseal() blocks following operations for the given memory range. 1> Unmapping, moving to another location, and shrinking the size, via munmap() and mremap(), can leave an empty space, therefore can be replaced with a VMA with a new set of attributes. 2> Moving or expanding a different VMA into the current location, via mremap(). 3> Modifying a VMA via mmap(MAP_FIXED). 4> Size expansion, via mremap(), does not appear to pose any specific risks to sealed VMAs. It is included anyway because the use case is unclear. In any case, users can rely on merging to expand a sealed VMA. 5> mprotect() and pkey_mprotect(). 6> Some destructive madvice() behaviors (e.g. MADV_DONTNEED) for anonymous memory, when users don't have write permission to the memory. Those behaviors can alter region contents by discarding pages, effectively a memset(0) for anonymous memory. The idea that inspired this patch comes from Stephen Röttger’s work in V8 CFI [5]. Chrome browser in ChromeOS will be the first user of this API. Indeed, the Chrome browser has very specific requirements for sealing, which are distinct from those of most applications. For example, in the case of libc, sealing is only applied to read-only (RO) or read-execute (RX) memory segments (such as .text and .RELRO) to prevent them from becoming writable, the lifetime of those mappings are tied to the lifetime of the process. Chrome wants to seal two large address space reservations that are managed by different allocators. The memory is mapped RW- and RWX respectively but write access to it is restricted using pkeys (or in the future ARM permission overlay extensions). The lifetime of those mappings are not tied to the lifetime of the process, therefore, while the memory is sealed, the allocators still need to free or discard the unused memory. For example, with madvise(DONTNEED). However, always allowing madvise(DONTNEED) on this range poses a security risk. For example if a jump instruction crosses a page boundary and the second page gets discarded, it will overwrite the target bytes with zeros and change the control flow. Checking write-permission before the discard operation allows us to control when the operation is valid. In this case, the madvise will only succeed if the executing thread has PKEY write permissions and PKRU changes are protected in software by control-flow integrity. Although the initial version of this patch series is targeting the Chrome browser as its first user, it became evident during upstream discussions that we would also want to ensure that the patch set eventually is a complete solution for memory sealing and compatible with other use cases. The specific scenario currently in mind is glibc's use case of loading and sealing ELF executables. To this end, Stephen is working on a change to glibc to add sealing support to the dynamic linker, which will seal all non-writable segments at startup. Once this work is completed, all applications will be able to automatically benefit from these new protections. In closing, I would like to formally acknowledge the valuable contributions received during the RFC process, which were instrumental in shaping this patch: Jann Horn: raising awareness and providing valuable insights on the destructive madvise operations. Liam R. Howlett: perf optimization. Linus Torvalds: assisting in defining system call signature and scope. Theo de Raadt: sharing the experiences and insight gained from implementing mimmutable() in OpenBSD. MM perf benchmarks ================== This patch adds a loop in the mprotect/munmap/madvise(DONTNEED) to check the VMAs’ sealing flag, so that no partial update can be made, when any segment within the given memory range is sealed. To measure the performance impact of this loop, two tests are developed. [8] The first is measuring the time taken for a particular system call, by using clock_gettime(CLOCK_MONOTONIC). The second is using PERF_COUNT_HW_REF_CPU_CYCLES (exclude user space). Both tests have similar results. The tests have roughly below sequence: for (i = 0; i < 1000, i++) create 1000 mappings (1 page per VMA) start the sampling for (j = 0; j < 1000, j++) mprotect one mapping stop and save the sample delete 1000 mappings calculates all samples. Below tests are performed on Intel(R) Pentium(R) Gold 7505 @ 2.00GHz, 4G memory, Chromebook. Based on the latest upstream code: The first test (measuring time) syscall__ vmas t t_mseal delta_ns per_vma % munmap__ 1 909 944 35 35 104% munmap__ 2 1398 1502 104 52 107% munmap__ 4 2444 2594 149 37 106% munmap__ 8 4029 4323 293 37 107% munmap__ 16 6647 6935 288 18 104% munmap__ 32 11811 12398 587 18 105% mprotect 1 439 465 26 26 106% mprotect 2 1659 1745 86 43 105% mprotect 4 3747 3889 142 36 104% mprotect 8 6755 6969 215 27 103% mprotect 16 13748 14144 396 25 103% mprotect 32 27827 28969 1142 36 104% madvise_ 1 240 262 22 22 109% madvise_ 2 366 442 76 38 121% madvise_ 4 623 751 128 32 121% madvise_ 8 1110 1324 215 27 119% madvise_ 16 2127 2451 324 20 115% madvise_ 32 4109 4642 534 17 113% The second test (measuring cpu cycle) syscall__ vmas cpu cmseal delta_cpu per_vma % munmap__ 1 1790 1890 100 100 106% munmap__ 2 2819 3033 214 107 108% munmap__ 4 4959 5271 312 78 106% munmap__ 8 8262 8745 483 60 106% munmap__ 16 13099 14116 1017 64 108% munmap__ 32 23221 24785 1565 49 107% mprotect 1 906 967 62 62 107% mprotect 2 3019 3203 184 92 106% mprotect 4 6149 6569 420 105 107% mprotect 8 9978 10524 545 68 105% mprotect 16 20448 21427 979 61 105% mprotect 32 40972 42935 1963 61 105% madvise_ 1 434 497 63 63 115% madvise_ 2 752 899 147 74 120% madvise_ 4 1313 1513 200 50 115% madvise_ 8 2271 2627 356 44 116% madvise_ 16 4312 4883 571 36 113% madvise_ 32 8376 9319 943 29 111% Based on the result, for 6.8 kernel, sealing check adds 20-40 nano seconds, or around 50-100 CPU cycles, per VMA. In addition, I applied the sealing to 5.10 kernel: The first test (measuring time) syscall__ vmas t tmseal delta_ns per_vma % munmap__ 1 357 390 33 33 109% munmap__ 2 442 463 21 11 105% munmap__ 4 614 634 20 5 103% munmap__ 8 1017 1137 120 15 112% munmap__ 16 1889 2153 263 16 114% munmap__ 32 4109 4088 -21 -1 99% mprotect 1 235 227 -7 -7 97% mprotect 2 495 464 -30 -15 94% mprotect 4 741 764 24 6 103% mprotect 8 1434 1437 2 0 100% mprotect 16 2958 2991 33 2 101% mprotect 32 6431 6608 177 6 103% madvise_ 1 191 208 16 16 109% madvise_ 2 300 324 24 12 108% madvise_ 4 450 473 23 6 105% madvise_ 8 753 806 53 7 107% madvise_ 16 1467 1592 125 8 108% madvise_ 32 2795 3405 610 19 122% The second test (measuring cpu cycle) syscall__ nbr_vma cpu cmseal delta_cpu per_vma % munmap__ 1 684 715 31 31 105% munmap__ 2 861 898 38 19 104% munmap__ 4 1183 1235 51 13 104% munmap__ 8 1999 2045 46 6 102% munmap__ 16 3839 3816 -23 -1 99% munmap__ 32 7672 7887 216 7 103% mprotect 1 397 443 46 46 112% mprotect 2 738 788 50 25 107% mprotect 4 1221 1256 35 9 103% mprotect 8 2356 2429 72 9 103% mprotect 16 4961 4935 -26 -2 99% mprotect 32 9882 10172 291 9 103% madvise_ 1 351 380 29 29 108% madvise_ 2 565 615 49 25 109% madvise_ 4 872 933 61 15 107% madvise_ 8 1508 1640 132 16 109% madvise_ 16 3078 3323 245 15 108% madvise_ 32 5893 6704 811 25 114% For 5.10 kernel, sealing check adds 0-15 ns in time, or 10-30 CPU cycles, there is even decrease in some cases. It might be interesting to compare 5.10 and 6.8 kernel The first test (measuring time) syscall__ vmas t_5_10 t_6_8 delta_ns per_vma % munmap__ 1 357 909 552 552 254% munmap__ 2 442 1398 956 478 316% munmap__ 4 614 2444 1830 458 398% munmap__ 8 1017 4029 3012 377 396% munmap__ 16 1889 6647 4758 297 352% munmap__ 32 4109 11811 7702 241 287% mprotect 1 235 439 204 204 187% mprotect 2 495 1659 1164 582 335% mprotect 4 741 3747 3006 752 506% mprotect 8 1434 6755 5320 665 471% mprotect 16 2958 13748 10790 674 465% mprotect 32 6431 27827 21397 669 433% madvise_ 1 191 240 49 49 125% madvise_ 2 300 366 67 33 122% madvise_ 4 450 623 173 43 138% madvise_ 8 753 1110 357 45 147% madvise_ 16 1467 2127 660 41 145% madvise_ 32 2795 4109 1314 41 147% The second test (measuring cpu cycle) syscall__ vmas cpu_5_10 c_6_8 delta_cpu per_vma % munmap__ 1 684 1790 1106 1106 262% munmap__ 2 861 2819 1958 979 327% munmap__ 4 1183 4959 3776 944 419% munmap__ 8 1999 8262 6263 783 413% munmap__ 16 3839 13099 9260 579 341% munmap__ 32 7672 23221 15549 486 303% mprotect 1 397 906 509 509 228% mprotect 2 738 3019 2281 1140 409% mprotect 4 1221 6149 4929 1232 504% mprotect 8 2356 9978 7622 953 423% mprotect 16 4961 20448 15487 968 412% mprotect 32 9882 40972 31091 972 415% madvise_ 1 351 434 82 82 123% madvise_ 2 565 752 186 93 133% madvise_ 4 872 1313 442 110 151% madvise_ 8 1508 2271 763 95 151% madvise_ 16 3078 4312 1234 77 140% madvise_ 32 5893 8376 2483 78 142% From 5.10 to 6.8 munmap: added 250-550 ns in time, or 500-1100 in cpu cycle, per vma. mprotect: added 200-750 ns in time, or 500-1200 in cpu cycle, per vma. madvise: added 33-50 ns in time, or 70-110 in cpu cycle, per vma. In comparison to mseal, which adds 20-40 ns or 50-100 CPU cycles, the increase from 5.10 to 6.8 is significantly larger, approximately ten times greater for munmap and mprotect. When I discuss the mm performance with Brian Makin, an engineer who worked on performance, it was brought to my attention that such performance benchmarks, which measuring millions of mm syscall in a tight loop, may not accurately reflect real-world scenarios, such as that of a database service. Also this is tested using a single HW and ChromeOS, the data from another HW or distribution might be different. It might be best to take this data with a grain of salt. This patch (of 5): Wire up mseal syscall for all architectures. Link: https://lkml.kernel.org/r/20240415163527.626541-1-jeffxu@chromium.org Link: https://lkml.kernel.org/r/20240415163527.626541-2-jeffxu@chromium.org Signed-off-by: Jeff Xu <jeffxu@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guenter Roeck <groeck@chromium.org> Cc: Jann Horn <jannh@google.com> [Bug #2] Cc: Jeff Xu <jeffxu@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jorge Lucangeli Obes <jorgelo@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muhammad Usama Anjum <usama.anjum@collabora.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Cc: Stephen Röttger <sroettger@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Amer Al Shanawany <amer.shanawany@gmail.com> Cc: Javier Carrasco <javier.carrasco.cruz@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-08m68k: Fix spinlock race in kernel thread creationMichael Schmitz1-1/+3
Context switching does take care to retain the correct lock owner across the switch from 'prev' to 'next' tasks. This does rely on interrupts remaining disabled for the entire duration of the switch. This condition is guaranteed for normal process creation and context switching between already running processes, because both 'prev' and 'next' already have interrupts disabled in their saved copies of the status register. The situation is different for newly created kernel threads. The status register is set to PS_S in copy_thread(), which does leave the IPL at 0. Upon restoring the 'next' thread's status register in switch_to() aka resume(), interrupts then become enabled prematurely. resume() then returns via ret_from_kernel_thread() and schedule_tail() where run queue lock is released (see finish_task_switch() and finish_lock_switch()). A timer interrupt calling scheduler_tick() before the lock is released in finish_task_switch() will find the lock already taken, with the current task as lock owner. This causes a spinlock recursion warning as reported by Guenter Roeck. As far as I can ascertain, this race has been opened in commit 533e6903bea0 ("m68k: split ret_from_fork(), simplify kernel_thread()") but I haven't done a detailed study of kernel history so it may well predate that commit. Interrupts cannot be disabled in the saved status register copy for kernel threads (init will complain about interrupts disabled when finally starting user space). Disable interrupts temporarily when switching the tasks' register sets in resume(). Note that a simple oriw 0x700,%sr after restoring sr is not enough here - this leaves enough of a race for the 'spinlock recursion' warning to still be observed. Tested on ARAnyM and qemu (Quadra 800 emulation). Fixes: 533e6903bea0 ("m68k: split ret_from_fork(), simplify kernel_thread()") Reported-by: Guenter Roeck <linux@roeck-us.net> Closes: https://lore.kernel.org/all/07811b26-677c-4d05-aeb4-996cd880b789@roeck-us.net Signed-off-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20240411033631.16335-1-schmitzmic@gmail.com Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-01-09Merge tag 'lsm-pr-20240105' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm Pull security module updates from Paul Moore: - Add three new syscalls: lsm_list_modules(), lsm_get_self_attr(), and lsm_set_self_attr(). The first syscall simply lists the LSMs enabled, while the second and third get and set the current process' LSM attributes. Yes, these syscalls may provide similar functionality to what can be found under /proc or /sys, but they were designed to support multiple, simultaneaous (stacked) LSMs from the start as opposed to the current /proc based solutions which were created at a time when only one LSM was allowed to be active at a given time. We have spent considerable time discussing ways to extend the existing /proc interfaces to support multiple, simultaneaous LSMs and even our best ideas have been far too ugly to support as a kernel API; after +20 years in the kernel, I felt the LSM layer had established itself enough to justify a handful of syscalls. Support amongst the individual LSM developers has been nearly unanimous, with a single objection coming from Tetsuo (TOMOYO) as he is worried that the LSM_ID_XXX token concept will make it more difficult for out-of-tree LSMs to survive. Several members of the LSM community have demonstrated the ability for out-of-tree LSMs to continue to exist by picking high/unused LSM_ID values as well as pointing out that many kernel APIs rely on integer identifiers, e.g. syscalls (!), but unfortunately Tetsuo's objections remain. My personal opinion is that while I have no interest in penalizing out-of-tree LSMs, I'm not going to penalize in-tree development to support out-of-tree development, and I view this as a necessary step forward to support the push for expanded LSM stacking and reduce our reliance on /proc and /sys which has occassionally been problematic for some container users. Finally, we have included the linux-api folks on (all?) recent revisions of the patchset and addressed all of their concerns. - Add a new security_file_ioctl_compat() LSM hook to handle the 32-bit ioctls on 64-bit systems problem. This patch includes support for all of the existing LSMs which provide ioctl hooks, although it turns out only SELinux actually cares about the individual ioctls. It is worth noting that while Casey (Smack) and Tetsuo (TOMOYO) did not give explicit ACKs to this patch, they did both indicate they are okay with the changes. - Fix a potential memory leak in the CALIPSO code when IPv6 is disabled at boot. While it's good that we are fixing this, I doubt this is something users are seeing in the wild as you need to both disable IPv6 and then attempt to configure IPv6 labeled networking via NetLabel/CALIPSO; that just doesn't make much sense. Normally this would go through netdev, but Jakub asked me to take this patch and of all the trees I maintain, the LSM tree seemed like the best fit. - Update the LSM MAINTAINERS entry with additional information about our process docs, patchwork, bug reporting, etc. I also noticed that the Lockdown LSM is missing a dedicated MAINTAINERS entry so I've added that to the pull request. I've been working with one of the major Lockdown authors/contributors to see if they are willing to step up and assume a Lockdown maintainer role; hopefully that will happen soon, but in the meantime I'll continue to look after it. - Add a handful of mailmap entries for Serge Hallyn and myself. * tag 'lsm-pr-20240105' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (27 commits) lsm: new security_file_ioctl_compat() hook lsm: Add a __counted_by() annotation to lsm_ctx.ctx calipso: fix memory leak in netlbl_calipso_add_pass() selftests: remove the LSM_ID_IMA check in lsm/lsm_list_modules_test MAINTAINERS: add an entry for the lockdown LSM MAINTAINERS: update the LSM entry mailmap: add entries for Serge Hallyn's dead accounts mailmap: update/replace my old email addresses lsm: mark the lsm_id variables are marked as static lsm: convert security_setselfattr() to use memdup_user() lsm: align based on pointer length in lsm_fill_user_ctx() lsm: consolidate buffer size handling into lsm_fill_user_ctx() lsm: correct error codes in security_getselfattr() lsm: cleanup the size counters in security_getselfattr() lsm: don't yet account for IMA in LSM_CONFIG_COUNT calculation lsm: drop LSM_ID_IMA LSM: selftests for Linux Security Module syscalls SELinux: Add selfattr hooks AppArmor: Add selfattr hooks Smack: implement setselfattr and getselfattr hooks ...
2024-01-08Merge tag 'vfs-6.8.mount' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs mount updates from Christian Brauner: "This contains the work to retrieve detailed information about mounts via two new system calls. This is hopefully the beginning of the end of the saga that started with fsinfo() years ago. The LWN articles in [1] and [2] can serve as a summary so we can avoid rehashing everything here. At LSFMM in May 2022 we got into a room and agreed on what we want to do about fsinfo(). Basically, split it into pieces. This is the first part of that agreement. Specifically, it is concerned with retrieving information about mounts. So this only concerns the mount information retrieval, not the mount table change notification, or the extended filesystem specific mount option work. That is separate work. Currently mounts have a 32bit id. Mount ids are already in heavy use by libmount and other low-level userspace but they can't be relied upon because they're recycled very quickly. We agreed that mounts should carry a unique 64bit id by which they can be referenced directly. This is now implemented as part of this work. The new 64bit mount id is exposed in statx() through the new STATX_MNT_ID_UNIQUE flag. If the flag isn't raised the old mount id is returned. If it is raised and the kernel supports the new 64bit mount id the flag is raised in the result mask and the new 64bit mount id is returned. New and old mount ids do not overlap so they cannot be conflated. Two new system calls are introduced that operate on the 64bit mount id: statmount() and listmount(). A summary of the api and usage can be found on LWN as well (cf. [3]) but of course, I'll provide a summary here as well. Both system calls rely on struct mnt_id_req. Which is the request struct used to pass the 64bit mount id identifying the mount to operate on. It is extensible to allow for the addition of new parameters and for future use in other apis that make use of mount ids. statmount() mimicks the semantics of statx() and exposes a set flags that userspace may raise in mnt_id_req to request specific information to be retrieved. A statmount() call returns a struct statmount filled in with information about the requested mount. Supported requests are indicated by raising the request flag passed in struct mnt_id_req in the @mask argument in struct statmount. Currently we do support: - STATMOUNT_SB_BASIC: Basic filesystem info - STATMOUNT_MNT_BASIC Mount information (mount id, parent mount id, mount attributes etc) - STATMOUNT_PROPAGATE_FROM Propagation from what mount in current namespace - STATMOUNT_MNT_ROOT Path of the root of the mount (e.g., mount --bind /bla /mnt returns /bla) - STATMOUNT_MNT_POINT Path of the mount point (e.g., mount --bind /bla /mnt returns /mnt) - STATMOUNT_FS_TYPE Name of the filesystem type as the magic number isn't enough due to submounts The string options STATMOUNT_MNT_{ROOT,POINT} and STATMOUNT_FS_TYPE are appended to the end of the struct. Userspace can use the offsets in @fs_type, @mnt_root, and @mnt_point to reference those strings easily. The struct statmount reserves quite a bit of space currently for future extensibility. This isn't really a problem and if this bothers us we can just send a follow-up pull request during this cycle. listmount() is given a 64bit mount id via mnt_id_req just as statmount(). It takes a buffer and a size to return an array of the 64bit ids of the child mounts of the requested mount. Userspace can thus choose to either retrieve child mounts for a mount in batches or iterate through the child mounts. For most use-cases it will be sufficient to just leave space for a few child mounts. But for big mount tables having an iterator is really helpful. Iterating through a mount table works by setting @param in mnt_id_req to the mount id of the last child mount retrieved in the previous listmount() call" Link: https://lwn.net/Articles/934469 [1] Link: https://lwn.net/Articles/829212 [2] Link: https://lwn.net/Articles/950569 [3] * tag 'vfs-6.8.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: add selftest for statmount/listmount fs: keep struct mnt_id_req extensible wire up syscalls for statmount/listmount add listmount(2) syscall statmount: simplify string option retrieval statmount: simplify numeric option retrieval add statmount(2) syscall namespace: extract show_path() helper mounts: keep list of mounts in an rbtree add unique mount ID
2023-12-14wire up syscalls for statmount/listmountMiklos Szeredi1-0/+2
Wire up all archs. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Link: https://lore.kernel.org/r/20231025140205.3586473-7-mszeredi@redhat.com Reviewed-by: Ian Kent <raven@themaw.net> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-13m68k, kexec: fix the incorrect ifdeffery and build dependency of CONFIG_KEXECBaoquan He1-1/+1
The select of KEXEC for CRASH_DUMP in kernel/Kconfig.kexec will be dropped, then compiling errors will be triggered if below config items are set: === CONFIG_CRASH_CORE=y CONFIG_KEXEC_CORE=y CONFIG_CRASH_DUMP=y === Here, change the dependency of buinding machine_kexec.o relocate_kernel.o and the ifdeffery in asm/kexe.h to CONFIG_KEXEC_CORE. Link: https://lkml.kernel.org/r/20231208073036.7884-3-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Eric DeVolder <eric_devolder@yahoo.com> Cc: Ignat Korchagin <ignat@cloudflare.com> Cc: kernel test robot <lkp@intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-13LSM: wireup Linux Security Module syscallsCasey Schaufler1-0/+3
Wireup lsm_get_self_attr, lsm_set_self_attr and lsm_list_modules system calls. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: linux-api@vger.kernel.org Reviewed-by: Mickaël Salaün <mic@digikod.net> [PM: forward ported beyond v6.6 due merge window changes] Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-03Merge tag 'm68knommu-for-v6.7' of ↵Linus Torvalds1-5/+8
git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu Pull m68knommu updates from Greg Ungerer: "A few changes, most of them related to fixing warnings when compiling with "W=1". These follow up Geert's recent changes for M68K for this too. These ones complete the fixes for the nommu and ColdFire specific code. Also a couple of other fixes to improve ROM default addressing and compiling for the Cleopatra boards. Summary: - improve default Kconfig ROM section settings - fix compilation for some Cleopatra boards - fixes and cleanups for warnings compiling with 'W=1'" * tag 'm68knommu-for-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68k: 68000: fix warning in timer code m68k: 68000: fix warnings in 68000 interrupt handling m68k: coldfire: remove unused variable in MMU code m68k: coldfire: fix warnings in uboot argument processing m68k: coldfire: make mcf_maskimr() static m68k: coldfire: ensure gpio prototypes visible m68k: coldfire: add and use "vectors.h" m68knommu: fix compilation for ColdFire/Cleopatra boards m68knommu: improve config ROM setting defaults
2023-11-02Merge tag 'asm-generic-6.7' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull ia64 removal and asm-generic updates from Arnd Bergmann: - The ia64 architecture gets its well-earned retirement as planned, now that there is one last (mostly) working release that will be maintained as an LTS kernel. - The architecture specific system call tables are updated for the added map_shadow_stack() syscall and to remove references to the long-gone sys_lookup_dcookie() syscall. * tag 'asm-generic-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: hexagon: Remove unusable symbols from the ptrace.h uapi asm-generic: Fix spelling of architecture arch: Reserve map_shadow_stack() syscall number for all architectures syscalls: Cleanup references to sys_lookup_dcookie() Documentation: Drop or replace remaining mentions of IA64 lib/raid6: Drop IA64 support Documentation: Drop IA64 from feature descriptions kernel: Drop IA64 support from sig_fault handlers arch: Remove Itanium (IA-64) architecture
2023-11-02Merge tag 'dma-mapping-6.7-2023-10-30' of ↵Linus Torvalds2-34/+2
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping updates from Christoph Hellwig: - get rid of the fake support for coherent DMA allocation on coldfire with caches (Christoph Hellwig) - add a few Kconfig dependencies so that Kconfig catches the use of invalid configurations (Christoph Hellwig) - fix a type in dma-debug output (Chuck Lever) - rewrite a comment in swiotlb (Sean Christopherson) * tag 'dma-mapping-6.7-2023-10-30' of git://git.infradead.org/users/hch/dma-mapping: dma-debug: Fix a typo in a debugging eye-catcher swiotlb: rewrite comment explaining why the source is preserved on DMA_FROM_DEVICE m68k: remove unused includes from dma.c m68k: don't provide arch_dma_alloc for nommu/coldfire net: fec: use dma_alloc_noncoherent for data cache enabled coldfire m68k: use the coherent DMA code for coldfire without data cache dma-direct: warn when coherent allocations aren't supported dma-direct: simplify the use atomic pool logic in dma_direct_alloc dma-direct: add a CONFIG_ARCH_HAS_DMA_ALLOC symbol dma-direct: add dependencies to CONFIG_DMA_GLOBAL_POOL
2023-11-01Merge tag 'm68k-for-v6.7-tag1' of ↵Linus Torvalds17-28/+69
git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k Pull m68k updates from Geert Uytterhoeven: - misc aesthetical improvements for the floating point emulator - remove the last user of strlcpy() - use kernel's generic libgcc functions - misc fixes for W=1 builds - misc indentation fixes - misc fixes and improvements - defconfig updates * tag 'm68k-for-v6.7-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: (72 commits) m68k: lib: Include <linux/libgcc.h> for __muldi3() m68k: fpsp040: Fix indentation by 5 spaces m68k: Fix indentation by 2 or 5 spaces in <asm/page_mm.h> m68k: kernel: Fix indentation by 7 spaces in traps.c m68k: sun3: Fix indentation by 5 or 7 spaces m68k: Fix indentation by 7 spaces in <asm/io_mm.h> m68k: defconfig: Update virt_defconfig for v6.6-rc3 m68k: defconfig: Update defconfigs for v6.6-rc1 m68k: io: Mark mmio read addresses as const m68k: Replace GPL 2.0+ README.legal boilerplate with SPDX m68k: sun3: Change led_pattern[] to unsigned char m68k: Add missing types to asm/irq.h m68k: sun3/3x: Add and use "sun3.h" m68k: sun3x: Make dvma_print() static m68k: sun3x: Make sun3x_halt() static m68k: sun3x: Do not mark dvma_map_iommu() inline m68k: sun3x: Fix signature of sun3_leds() m68k: sun3: Make sun3_platform_init() static m68k: sun3: Make print_pte() static m68k: sun3: Annotate prom_printf() with __printf() ...
2023-10-23m68k: coldfire: fix warnings in uboot argument processingGreg Ungerer1-5/+8
When building with W=1: CC arch/m68k/kernel/uboot.o arch/m68k/kernel/uboot.c: In function ‘parse_uboot_commandline’: arch/m68k/kernel/uboot.c:68:36: warning: variable ‘uboot_initrd_end’ set but not used [-Wunused-but-set-variable] unsigned long uboot_initrd_start, uboot_initrd_end; ^~~~~~~~~~~~~~~~ arch/m68k/kernel/uboot.c:68:16: warning: variable ‘uboot_initrd_start’ set but not used [-Wunused-but-set-variable] unsigned long uboot_initrd_start, uboot_initrd_end; ^~~~~~~~~~~~~~~~~~ arch/m68k/kernel/uboot.c:66:16: warning: variable ‘uboot_kbd’ set but not used [-Wunused-but-set-variable] unsigned long uboot_kbd; ^~~~~~~~~ arch/m68k/kernel/uboot.c: At top level: arch/m68k/kernel/uboot.c:90:13: warning: no previous prototype for ‘process_uboot_commandline’ [-Wmissing-prototypes] __init void process_uboot_commandline(char *commandp, int size) ^~~~~~~~~~~~~~~~~~~~~~~~~ A couple of issues here. Firstly we already have a bootinfo.h that has a prototype for process_uboot_commandline(), we should include that. Secondly uboot_kbd is not used at all and can be removed. Thirdly the conditional code based on CONFIG_BLK_DEV_INITRD means that sometimes uboot_initrd_start and uboot_initrd_end are not needed. Make their declaration and asignment conditional on CONFIG_BLK_DEV_INITRD same as the code that uses them. Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2023-10-22m68k: remove unused includes from dma.cChristoph Hellwig1-9/+0
dma.c doesn't need most of the headers it includes. Also there is no point in undefining the DEBUG symbol given that it isn't used anywhere in this small file. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Greg Ungerer <gerg@linux-m68k.org>
2023-10-22m68k: don't provide arch_dma_alloc for nommu/coldfireChristoph Hellwig1-23/+0
Coldfire cores configured with a data cache can't provide coherent DMA allocations at all. Instead of returning non-coherent kernel memory in this case, return NULL and fail the allocation. The only driver that used to rely on the previous behavior (fec) has been switched to use non-coherent allocations for this case recently. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> Tested-by: Greg Ungerer <gerg@linux-m68k.org>
2023-10-22m68k: use the coherent DMA code for coldfire without data cacheChristoph Hellwig2-2/+2
Coldfire cores configured without a data cache are DMA coherent and should thus simply use the simple coherent version of dma-direct. Introduce a new COLDFIRE_COHERENT_DMA Kconfig symbol as a convenient short hand for such configurations, and a M68K_NONCOHERENT_DMA symbol for all cases where we need to build non-coherent DMA infrastructure to simplify the Kconfig and code conditionals. Not building the non-coherent DMA code slightly reduces the code size for such configurations. Numers for m5249evb_defconfig below: text data bss dec hex filename 2896158 401052 65392 3362602 334f2a vmlinux.before 2895166 400988 65392 3361546 334b0a vmlinux.after Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Greg Ungerer <gerg@linux-m68k.org>
2023-10-16m68k: kernel: Fix indentation by 7 spaces in traps.cGeert Uytterhoeven1-4/+4
Indentation should use TABs, not spaces. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/d1b38c9d389c1135f7856cf5f90852c2f1584c50.1696602993.git.geert@linux-m68k.org
2023-10-06arch: Reserve map_shadow_stack() syscall number for all architecturesSohil Mehta1-0/+1
commit c35559f94ebc ("x86/shstk: Introduce map_shadow_stack syscall") recently added support for map_shadow_stack() but it is limited to x86 only for now. There is a possibility that other architectures (namely, arm64 and RISC-V), that are implementing equivalent support for shadow stacks, might need to add support for it. Independent of that, reserving arch-specific syscall numbers in the syscall tables of all architectures is good practice and would help avoid future conflicts. map_shadow_stack() is marked as a conditional syscall in sys_ni.c. Adding it to the syscall tables of other architectures is harmless and would return ENOSYS when exercised. Note, map_shadow_stack() was assigned #453 during the merge process since #452 was taken by fchmodat2(). For Powerpc, map it to sys_ni_syscall() as is the norm for Powerpc syscall tables. For Alpha, map_shadow_stack() takes up #563 as Alpha still diverges from the common syscall numbering system in the other architectures. Link: https://lore.kernel.org/lkml/20230515212255.GA562920@debug.ba.rivosinc.com/ Link: https://lore.kernel.org/lkml/b402b80b-a7c6-4ef0-b977-c0f5f582b78a@sirena.org.uk/ Signed-off-by: Sohil Mehta <sohil.mehta@intel.com> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-10-06m68k: Replace GPL 2.0+ README.legal boilerplate with SPDXGeert Uytterhoeven2-11/+4
Upstream Linux never had a "README.legal" file, but it was present in early source releases of Linux/m68k. It contained a simple copyright notice and a link to a version of the "COPYING" file that predated the addition of the "only valid GPL version is v2" clause. Get rid of the references to non-existent files by replacing the boilerplate with SPDX license identifiers. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Greg Ungerer <gerg@linux-m68k.org> Link: https://lore.kernel.org/r/23430c233728ab02ec0af8e714994398d383137a.1695031668.git.geert@linux-m68k.org
2023-10-06m68k: sun3/3x: Add and use "sun3.h"Geert Uytterhoeven1-1/+1
When building with W=1: arch/m68k/sun3/idprom.c:86:6: warning: no previous prototype for ‘sun3_get_model’ [-Wmissing-prototypes] 86 | void sun3_get_model(char *model) | ^~~~~~~~~~~~~~ arch/m68k/sun3/config.c:53:24: warning: no previous prototype for ‘sun3_init’ [-Wmissing-prototypes] 53 | asmlinkage void __init sun3_init(void) | ^~~~~~~~~ arch/m68k/sun3/mmu_emu.c:117:6: warning: no previous prototype for ‘print_pte_vaddr’ [-Wmissing-prototypes] 117 | void print_pte_vaddr (unsigned long vaddr) | ^~~~~~~~~~~~~~~ arch/m68k/sun3/mmu_emu.c:126:13: warning: no previous prototype for ‘mmu_emu_init’ [-Wmissing-prototypes] 126 | void __init mmu_emu_init(unsigned long bootmem_end) | ^~~~~~~~~~~~ arch/m68k/sun3/mmu_emu.c:353:5: warning: no previous prototype for ‘mmu_emu_handle_fault’ [-Wmissing-prototypes] 353 | int mmu_emu_handle_fault (unsigned long vaddr, int read_flag, int kernel_fault) | ^~~~~~~~~~~~~~~~~~~~ arch/m68k/sun3/leds.c:6:6: warning: no previous prototype for ‘sun3_leds’ [-Wmissing-prototypes] 6 | void sun3_leds(unsigned char byte) | ^~~~~~~~~ arch/m68k/sun3/intersil.c:27:5: warning: no previous prototype for ‘sun3_hwclk’ [-Wmissing-prototypes] 27 | int sun3_hwclk(int set, struct rtc_time *t) | ^~~~~~~~~~ arch/m68k/sun3x/config.c:30:6: warning: no previous prototype for ‘sun3_leds’ [-Wmissing-prototypes] 30 | void sun3_leds(unsigned char byte) | ^~~~~~~~~ Fix this by introducing a new header file "sun3.h" for holding the prototypes of functions implemented in arch/m68k/sun3/ and arch/m68k/sun3x/. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/87856ef9ef8955f459fb691faca921c0a688bc80.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: mvme16x: Add and use "mvme16x.h"Geert Uytterhoeven1-2/+2
When building with W=1: arch/m68k/mvme16x/config.c:208:6: warning: no previous prototype for ‘mvme16x_cons_write’ [-Wmissing-prototypes] 208 | void mvme16x_cons_write(struct console *co, const char *str, unsigned count) | ^~~~~~~~~~~~~~~~~~ Fix this by introducing a new header file "mvme16x.h" for holding the prototypes of functions implemented in arch/m68k/mvme16x/. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/6200cc3b26fad215c4524748af04692e38c5ecd2.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: mm: Add and use "fault.h"Geert Uytterhoeven2-6/+2
When building with W=1: arch/m68k/mm/fault.c:22:5: warning: no previous prototype for ‘send_fault_sig’ [-Wmissing-prototypes] 22 | int send_fault_sig(struct pt_regs *regs) | ^~~~~~~~~~~~~~ arch/m68k/mm/fault.c:68:5: warning: no previous prototype for ‘do_page_fault’ [-Wmissing-prototypes] 68 | int do_page_fault(struct pt_regs *regs, unsigned long address, | ^~~~~~~~~~~~~ Fix this by introducing a new header file "fault.h" for holding the prototypes of functions implemented in arch/m68k/mm/fault.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/ef004b8cfe4aac892aa0fb7714c2ed81a02a9b89.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: mm: Move paging_init() to common <asm/pgtable.h>Geert Uytterhoeven1-2/+0
When building with W=1: arch/m68k/mm/motorola.c:414:13: warning: no previous prototype for ‘paging_init’ [-Wmissing-prototypes] 414 | void __init paging_init(void) | ^~~~~~~~~~~ arch/m68k/mm/sun3mmu.c:36:13: warning: no previous prototype for ‘paging_init’ [-Wmissing-prototypes] 36 | void __init paging_init(void) | ^~~~~~~~~~~ Fix this by consolidating the multiple prototypes into the common <asm/pgtable.h>. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/1b03fde54f205e972e19959b8e335022205d538c.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add and use "vectors.h"Geert Uytterhoeven2-0/+5
When building with W=1: arch/m68k/kernel/vectors.c:52:13: warning: no previous prototype for ‘base_trap_init’ [-Wmissing-prototypes] 52 | void __init base_trap_init(void) | ^~~~~~~~~~~~~~ Fix this by introducing a new header file "vectors.h" for holding the prototypes of functions implemented in arch/m68k/kernel/vectors.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/bd0a2f65bc1681dc45e2b24951bd89f9ddbe2eef.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add and use "traps.h"Geert Uytterhoeven2-0/+12
When building with W=1: arch/m68k/kernel/traps.c:754:17: warning: no previous prototype for ‘buserr_c’ [-Wmissing-prototypes] 754 | asmlinkage void buserr_c(struct frame *fp) | ^~~~~~~~ arch/m68k/kernel/traps.c:1140:17: warning: no previous prototype for ‘set_esp0’ [-Wmissing-prototypes] 1140 | asmlinkage void set_esp0(unsigned long ssp) | ^~~~~~~~ arch/m68k/kernel/traps.c:1155:17: warning: no previous prototype for ‘fpemu_signal’ [-Wmissing-prototypes] 1155 | asmlinkage void fpemu_signal(int signal, int code, void *addr) | ^~~~~~~~~~~~ arch/m68k/kernel/traps.c:1149:17: warning: no previous prototype for ‘fpsp040_die’ [-Wmissing-prototypes] 1149 | asmlinkage void fpsp040_die(void) | ^~~~~~~~~~~ Fix this by introducing a new header file "traps.h" for holding the prototypes of functions implemented in arch/m68k/kernel/traps.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/652cbbb1c9e339980a86068ebdd0a69362324af8.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add and use "signal.h"Geert Uytterhoeven2-0/+9
When building with W=1: arch/m68k/kernel/signal.c:756:18: warning: no previous prototype for ‘do_sigreturn’ [-Wmissing-prototypes] 756 | asmlinkage void *do_sigreturn(struct pt_regs *regs, struct switch_stack *sw) | ^~~~~~~~~~~~ arch/m68k/kernel/signal.c:783:18: warning: no previous prototype for ‘do_rt_sigreturn’ [-Wmissing-prototypes] 783 | asmlinkage void *do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw) | ^~~~~~~~~~~~~~~ arch/m68k/kernel/signal.c:1112:17: warning: no previous prototype for ‘do_notify_resume’ [-Wmissing-prototypes] 1112 | asmlinkage void do_notify_resume(struct pt_regs *regs) | ^~~~~~~~~~~~~~~~ Fix this by introducing a new header file "signal.h" for holding the prototypes of functions implemented in arch/m68k/kernel/signal.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/25cecda80698829cec18721a9d0f058cc69df0cc.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add and use "ptrace.h"Geert Uytterhoeven2-0/+8
When building with W=1: arch/m68k/kernel/ptrace.c:275:16: warning: no previous prototype for ‘syscall_trace_enter’ [-Wmissing-prototypes] 275 | asmlinkage int syscall_trace_enter(void) | ^~~~~~~~~~~~~~~~~~~ arch/m68k/kernel/ptrace.c:288:17: warning: no previous prototype for ‘syscall_trace_leave’ [-Wmissing-prototypes] 288 | asmlinkage void syscall_trace_leave(void) | ^~~~~~~~~~~~~~~~~~~ Fix this by introducing a new header file "ptrace.h" for holding the prototypes of functions implemented in arch/m68k/kernel/ptrace.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/b4b3577b2149ebd65c3b3c7acccebc0e7e596f9d.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add and use "process.h"Geert Uytterhoeven2-0/+9
When building with W=1: arch/m68k/kernel/process.c:115:16: warning: no previous prototype for ‘m68k_clone’ [-Wmissing-prototypes] 115 | asmlinkage int m68k_clone(struct pt_regs *regs) | ^~~~~~~~~~ arch/m68k/kernel/process.c:136:16: warning: no previous prototype for ‘m68k_clone3’ [-Wmissing-prototypes] 136 | asmlinkage int m68k_clone3(struct pt_regs *regs) | ^~~~~~~~~~~ Fix this by introducing a new header file "process.h" for holding the prototypes of functions implemented in arch/m68k/kernel/process.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/5e50257d8fcae3eb202ce5f439dc29c09cb6c44f.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add and use "ints.h"Geert Uytterhoeven2-0/+9
When building with W=1: arch/m68k/kernel/ints.c:165:17: warning: no previous prototype for ‘handle_badint’ [-Wmissing-prototypes] 165 | asmlinkage void handle_badint(struct pt_regs *regs) | ^~~~~~~~~~~~~ Fix this by introducing a new header file "ints.h" for holding the prototypes of functions implemented in arch/m68k/kernel/ints.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/dc65d01ca4c7de94ce814e5b5e1f726fff97566b.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add and use <asm/syscalls.h>Geert Uytterhoeven1-0/+1
When building with W=1: arch/m68k/kernel/sys_m68k.c:40:17: warning: no previous prototype for ‘sys_mmap2’ [-Wmissing-prototypes] 40 | asmlinkage long sys_mmap2(unsigned long addr, unsigned long len, | ^~~~~~~~~ arch/m68k/kernel/sys_m68k.c:378:1: warning: no previous prototype for ‘sys_cacheflush’ [-Wmissing-prototypes] 378 | sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len) | ^~~~~~~~~~~~~~ arch/m68k/kernel/sys_m68k.c:463:1: warning: no previous prototype for ‘sys_atomic_cmpxchg_32’ [-Wmissing-prototypes] 463 | sys_atomic_cmpxchg_32(unsigned long newval, int oldval, int d3, int d4, int d5, | ^~~~~~~~~~~~~~~~~~~~~ arch/m68k/kernel/sys_m68k.c:564:16: warning: no previous prototype for ‘sys_getpagesize’ [-Wmissing-prototypes] 564 | asmlinkage int sys_getpagesize(void) | ^~~~~~~~~~~~~~~ arch/m68k/kernel/sys_m68k.c:569:26: warning: no previous prototype for ‘sys_get_thread_area’ [-Wmissing-prototypes] 569 | asmlinkage unsigned long sys_get_thread_area(void) | ^~~~~~~~~~~~~~~~~~~ arch/m68k/kernel/sys_m68k.c:574:16: warning: no previous prototype for ‘sys_set_thread_area’ [-Wmissing-prototypes] 574 | asmlinkage int sys_set_thread_area(unsigned long tp) | ^~~~~~~~~~~~~~~~~~~ arch/m68k/kernel/sys_m68k.c:580:16: warning: no previous prototype for ‘sys_atomic_barrier’ [-Wmissing-prototypes] 580 | asmlinkage int sys_atomic_barrier(void) | ^~~~~~~~~~~~~~~~~~ Fix this by introducing a new header file <asm/syscalls.h> for holding the prototypes for m68k-specific syscalls, and including the generic ones. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/80b721eeb499562cd5d49887b0eee10dd172c88d.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Make bad_super_trap() staticGeert Uytterhoeven1-1/+1
When building with W=1: arch/m68k/kernel/traps.c:968:6: warning: no previous prototype for ‘bad_super_trap’ [-Wmissing-prototypes] 968 | void bad_super_trap (struct frame *fp) | ^~~~~~~~~~~~~~ Fix this by making bad_super_trap() static. There was never a user outside arch/m68k/kernel/traps.c. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/1e0b67a355d7e1bcb40811eced41d3080e8f4d20.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Include <linux/cpu.h> for trap_init()Geert Uytterhoeven1-0/+1
When building with W=1: arch/m68k/kernel/vectors.c:74:13: warning: no previous prototype for ‘trap_init’ [-Wmissing-prototypes] 74 | void __init trap_init (void) | ^~~~~~~~~ Fix this by including <linux/cpu.h>. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/42e7055fab50deda1f7cd648982e90b7ab28fdc3.1694613528.git.geert@linux-m68k.org
2023-10-06m68k: kernel: Add missing asmlinkage to do_notify_resume()Geert Uytterhoeven1-1/+1
do_notify_resume() is called from assembly code, so it should be marked asmlinkage for documentation purposes. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/e24d63ec4332316e859125caa8d07c0589603cfd.1694613528.git.geert@linux-m68k.org
2023-10-03syscalls: Cleanup references to sys_lookup_dcookie()Sohil Mehta1-1/+1
commit 'be65de6b03aa ("fs: Remove dcookies support")' removed the syscall definition for lookup_dcookie. However, syscall tables still point to the old sys_lookup_dcookie() definition. Update syscall tables of all architectures to directly point to sys_ni_syscall() instead. Signed-off-by: Sohil Mehta <sohil.mehta@intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Namhyung Kim <namhyung@kernel.org> # for perf Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-09-21futex: Add sys_futex_requeue()peterz@infradead.org1-0/+1
Finish off the 'simple' futex2 syscall group by adding sys_futex_requeue(). Unlike sys_futex_{wait,wake}() its arguments are too numerous to fit into a regular syscall. As such, use struct futex_waitv to pass the 'source' and 'destination' futexes to the syscall. This syscall implements what was previously known as FUTEX_CMP_REQUEUE and uses {val, uaddr, flags} for source and {uaddr, flags} for destination. This design explicitly allows requeueing between different types of futex by having a different flags word per uaddr. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230921105248.511860556@noisy.programming.kicks-ass.net
2023-09-21futex: Add sys_futex_wait()peterz@infradead.org1-0/+1
To complement sys_futex_waitv()/wake(), add sys_futex_wait(). This syscall implements what was previously known as FUTEX_WAIT_BITSET except it uses 'unsigned long' for the value and bitmask arguments, takes timespec and clockid_t arguments for the absolute timeout and uses FUTEX2 flags. The 'unsigned long' allows FUTEX2_SIZE_U64 on 64bit platforms. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230921105248.164324363@noisy.programming.kicks-ass.net
2023-09-21futex: Add sys_futex_wake()peterz@infradead.org1-0/+1
To complement sys_futex_waitv() add sys_futex_wake(). This syscall implements what was previously known as FUTEX_WAKE_BITSET except it uses 'unsigned long' for the bitmask and takes FUTEX2 flags. The 'unsigned long' allows FUTEX2_SIZE_U64 on 64bit platforms. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230921105247.936205525@noisy.programming.kicks-ass.net
2023-09-04Merge tag 'm68knommu-for-v6.6' of ↵Linus Torvalds1-6/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu Pull m68knommu updates from Greg Ungerer: "Two changes, one a trivial white space clean up, the other removes the unnecessary local pcibios_setup() code" * tag 'm68knommu-for-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68k: coldfire: dma_timer: ERROR: "foo __init bar" should be "foo __init bar" m68k/pci: Drop useless pcibios_setup()
2023-08-28Merge tag 'v6.6-vfs.fchmodat2' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull fchmodat2 system call from Christian Brauner: "This adds the fchmodat2() system call. It is a revised version of the fchmodat() system call, adding a missing flag argument. Support for both AT_SYMLINK_NOFOLLOW and AT_EMPTY_PATH are included. Adding this system call revision has been a longstanding request but so far has always fallen through the cracks. While the kernel implementation of fchmodat() does not have a flag argument the libc provided POSIX-compliant fchmodat(3) version does. Both glibc and musl have to implement a workaround in order to support AT_SYMLINK_NOFOLLOW (see [1] and [2]). The workaround is brittle because it relies not just on O_PATH and O_NOFOLLOW semantics and procfs magic links but also on our rather inconsistent symlink semantics. This gives userspace a proper fchmodat2() system call that libcs can use to properly implement fchmodat(3) and allows them to get rid of their hacks. In this case it will immediately benefit them as the current workaround is already defunct because of aformentioned inconsistencies. In addition to AT_SYMLINK_NOFOLLOW, give userspace the ability to use AT_EMPTY_PATH with fchmodat2(). This is already possible with fchownat() so there's no reason to not also support it for fchmodat2(). The implementation is simple and comes with selftests. Implementation of the system call and wiring up the system call are done as separate patches even though they could arguably be one patch. But in case there are merge conflicts from other system call additions it can be beneficial to have separate patches" Link: https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/fchmodat.c;h=17eca54051ee28ba1ec3f9aed170a62630959143;hb=a492b1e5ef7ab50c6fdd4e4e9879ea5569ab0a6c#l35 [1] Link: https://git.musl-libc.org/cgit/musl/tree/src/stat/fchmodat.c?id=718f363bc2067b6487900eddc9180c84e7739f80#n28 [2] * tag 'v6.6-vfs.fchmodat2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: selftests: fchmodat2: remove duplicate unneeded defines fchmodat2: add support for AT_EMPTY_PATH selftests: Add fchmodat2 selftest arch: Register fchmodat2, usually as syscall 452 fs: Add fchmodat2() Non-functional cleanup of a "__user * filename"
2023-08-21m68k/pci: Drop useless pcibios_setup()Bjorn Helgaas1-6/+0
The PCI core supplies a weak pcibios_setup() implementation that is identical to the m68k implementation. Remove the m68k version since it is unnecessary. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2023-07-27arch: Register fchmodat2, usually as syscall 452Palmer Dabbelt1-0/+1
This registers the new fchmodat2 syscall in most places as nuber 452, with alpha being the exception where it's 562. I found all these sites by grepping for fspick, which I assume has found me everything. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Alexey Gladkov <legion@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Message-Id: <a677d521f048e4ca439e7080a5328f21eb8e960e.1689092120.git.legion@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-24m68k: Fix invalid .section syntaxBen Hutchings1-2/+2
gas supports several different forms for .section for ELF targets, including: .section NAME [, "FLAGS"[, @TYPE[,FLAG_SPECIFIC_ARGUMENTS]]] and: .section "NAME"[, #FLAGS...] In several places we use a mix of these two forms: .section NAME, #FLAGS... A current development snapshot of binutils (2.40.50.20230611) treats this mixed syntax as an error. Change to consistently use: .section NAME, "FLAGS" as is used elsewhere in the kernel. Link: https://buildd.debian.org/status/fetch.php?pkg=linux&arch=m68k&ver=6.4%7Erc6-1%7Eexp1&stamp=1686907300&raw=1 Signed-off-by: Ben Hutchings <benh@debian.org> Tested-by: Jan-Benedict Glaw <jbglaw@lug-owl.de> Link: https://lore.kernel.org/r/ZIyBaueWT9jnTwRC@decadent.org.uk Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2023-06-28Merge tag 'mm-stable-2023-06-24-19-15' of ↵Linus Torvalds2-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull mm updates from Andrew Morton: - Yosry Ahmed brought back some cgroup v1 stats in OOM logs - Yosry has also eliminated cgroup's atomic rstat flushing - Nhat Pham adds the new cachestat() syscall. It provides userspace with the ability to query pagecache status - a similar concept to mincore() but more powerful and with improved usability - Mel Gorman provides more optimizations for compaction, reducing the prevalence of page rescanning - Lorenzo Stoakes has done some maintanance work on the get_user_pages() interface - Liam Howlett continues with cleanups and maintenance work to the maple tree code. Peng Zhang also does some work on maple tree - Johannes Weiner has done some cleanup work on the compaction code - David Hildenbrand has contributed additional selftests for get_user_pages() - Thomas Gleixner has contributed some maintenance and optimization work for the vmalloc code - Baolin Wang has provided some compaction cleanups, - SeongJae Park continues maintenance work on the DAMON code - Huang Ying has done some maintenance on the swap code's usage of device refcounting - Christoph Hellwig has some cleanups for the filemap/directio code - Ryan Roberts provides two patch series which yield some rationalization of the kernel's access to pte entries - use the provided APIs rather than open-coding accesses - Lorenzo Stoakes has some fixes to the interaction between pagecache and directio access to file mappings - John Hubbard has a series of fixes to the MM selftesting code - ZhangPeng continues the folio conversion campaign - Hugh Dickins has been working on the pagetable handling code, mainly with a view to reducing the load on the mmap_lock - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment from 128 to 8 - Domenico Cerasuolo has improved the zswap reclaim mechanism by reorganizing the LRU management - Matthew Wilcox provides some fixups to make gfs2 work better with the buffer_head code - Vishal Moola also has done some folio conversion work - Matthew Wilcox has removed the remnants of the pagevec code - their functionality is migrated over to struct folio_batch * tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits) mm/hugetlb: remove hugetlb_set_page_subpool() mm: nommu: correct the range of mmap_sem_read_lock in task_mem() hugetlb: revert use of page_cache_next_miss() Revert "page cache: fix page_cache_next/prev_miss off by one" mm/vmscan: fix root proactive reclaim unthrottling unbalanced node mm: memcg: rename and document global_reclaim() mm: kill [add|del]_page_to_lru_list() mm: compaction: convert to use a folio in isolate_migratepages_block() mm: zswap: fix double invalidate with exclusive loads mm: remove unnecessary pagevec includes mm: remove references to pagevec mm: rename invalidate_mapping_pagevec to mapping_try_invalidate mm: remove struct pagevec net: convert sunrpc from pagevec to folio_batch i915: convert i915_gpu_error to use a folio_batch pagevec: rename fbatch_count() mm: remove check_move_unevictable_pages() drm: convert drm_gem_put_pages() to use a folio_batch i915: convert shmem_sg_free_table() to use a folio_batch scatterlist: add sg_set_folio() ...
2023-06-26Merge tag 'x86-boot-2023-06-26' of ↵Linus Torvalds1-1/+2
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Thomas Gleixner: "Initialize FPU late. Right now FPU is initialized very early during boot. There is no real requirement to do so. The only requirement is to have it done before alternatives are patched. That's done in check_bugs() which does way more than what the function name suggests. So first rename check_bugs() to arch_cpu_finalize_init() which makes it clear what this is about. Move the invocation of arch_cpu_finalize_init() earlier in start_kernel() as it has to be done before fork_init() which needs to know the FPU register buffer size. With those prerequisites the FPU initialization can be moved into arch_cpu_finalize_init(), which removes it from the early and fragile part of the x86 bringup" * tag 'x86-boot-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mem_encrypt: Unbreak the AMD_MEM_ENCRYPT=n build x86/fpu: Move FPU initialization into arch_cpu_finalize_init() x86/fpu: Mark init functions __init x86/fpu: Remove cpuinfo argument from init functions x86/init: Initialize signal frame size late init, x86: Move mem_encrypt_init() into arch_cpu_finalize_init() init: Invoke arch_cpu_finalize_init() earlier init: Remove check_bugs() leftovers um/cpu: Switch to arch_cpu_finalize_init() sparc/cpu: Switch to arch_cpu_finalize_init() sh/cpu: Switch to arch_cpu_finalize_init() mips/cpu: Switch to arch_cpu_finalize_init() m68k/cpu: Switch to arch_cpu_finalize_init() loongarch/cpu: Switch to arch_cpu_finalize_init() ia64/cpu: Switch to arch_cpu_finalize_init() ARM: cpu: Switch to arch_cpu_finalize_init() x86/cpu: Switch to arch_cpu_finalize_init() init: Provide arch_cpu_finalize_init()
2023-06-20m68k: allow pte_offset_map[_lock]() to failHugh Dickins1-0/+2
In rare transient cases, not yet made possible, pte_offset_map() and pte_offset_map_lock() may not find a page table: handle appropriately. Restructure cf_tlb_miss() with a pte_unmap() (previously omitted) at label out, followed by one local_irq_restore() for all. Link: https://lkml.kernel.org/r/795f6a7-bcca-cdf-ad2a-fbdaa232998c@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: David Hildenbrand <david@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: John David Anglin <dave.anglin@bell.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-16m68k/cpu: Switch to arch_cpu_finalize_init()Thomas Gleixner1-1/+2
check_bugs() is about to be phased out. Switch over to the new arch_cpu_finalize_init() implementation. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230613224545.254342916@linutronix.de
2023-06-10cachestat: wire up cachestat for other architecturesNhat Pham1-0/+1
cachestat is previously only wired in for x86 (and architectures using the generic unistd.h table): https://lore.kernel.org/lkml/20230503013608.2431726-1-nphamcs@gmail.com/ This patch wires cachestat in for all the other architectures. [nphamcs@gmail.com: wire up cachestat for arm64] Link: https://lkml.kernel.org/r/20230511092843.3896327-1-nphamcs@gmail.com Link: https://lkml.kernel.org/r/20230510195806.2902878-1-nphamcs@gmail.com Signed-off-by: Nhat Pham <nphamcs@gmail.com> Tested-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Heiko Carstens <hca@linux.ibm.com> [s390] Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Chris Zankel <chris@zankel.net> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-05-22m68k: Move signal frame following exception on 68020/030Finn Thain1-4/+10
On 68030/020, an instruction such as, moveml %a2-%a3/%a5,%sp@- may cause a stack page fault during instruction execution (i.e. not at an instruction boundary) and produce a format 0xB exception frame. In this situation, the value of USP will be unreliable. If a signal is to be delivered following the exception, this USP value is used to calculate the location for a signal frame. This can result in a corrupted user stack. The corruption was detected in dash (actually in glibc) where it showed up as an intermittent "stack smashing detected" message and crash following signal delivery for SIGCHLD. It was hard to reproduce that failure because delivery of the signal raced with the page fault and because the kernel places an unpredictable gap of up to 7 bytes between the USP and the signal frame. A format 0xB exception frame can be produced by a bus error or an address error. The 68030 Users Manual says that address errors occur immediately upon detection during instruction prefetch. The instruction pipeline allows prefetch to overlap with other instructions, which means an address error can arise during the execution of a different instruction. So it seems likely that this patch may help in the address error case also. Reported-and-tested-by: Stan Johnson <userm57@yahoo.com> Link: https://lore.kernel.org/all/CAMuHMdW3yD22_ApemzW_6me3adq6A458u1_F0v-1EYwK_62jPA@mail.gmail.com/ Cc: Michael Schmitz <schmitzmic@gmail.com> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: stable@vger.kernel.org Co-developed-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Finn Thain <fthain@linux-m68k.org> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/9e66262a754fcba50208aa424188896cc52a1dd1.1683365892.git.fthain@linux-m68k.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>