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2021-03-15s390/vtime: fix increased steal time accountingGerald Schaefer1-1/+1
Commit 152e9b8676c6e ("s390/vtime: steal time exponential moving average") inadvertently changed the input value for account_steal_time() from "cputime_to_nsecs(steal)" to just "steal", resulting in broken increased steal time accounting. Fix this by changing it back to "cputime_to_nsecs(steal)". Fixes: 152e9b8676c6e ("s390/vtime: steal time exponential moving average") Cc: <stable@vger.kernel.org> # 5.1 Reported-by: Sabine Forkel <sabine.forkel@de.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-15s390/cpumf: disable preemption when accessing per-cpu variableThomas Richter1-1/+2
The following BUG message was triggered repeatedly when complete counter sets are extracted from the CPUMF: BUG: using smp_processor_id() in preemptible [00000000] code: psvc-readsets/7759 caller is cf_diag_needspace+0x2c/0x100 CPU: 7 PID: 7759 Comm: psvc-readsets Not tainted 5.12.0 Hardware name: IBM 3906 M03 703 (LPAR) Call Trace: [<00000000c7043f78>] show_stack+0x90/0xf8 [<00000000c705776a>] dump_stack+0xba/0x108 [<00000000c705d91c>] check_preemption_disabled+0xec/0xf0 [<00000000c63eb1c4>] cf_diag_needspace+0x2c/0x100 [<00000000c63ecbcc>] cf_diag_ioctl_start+0x10c/0x240 [<00000000c63ece9a>] cf_diag_ioctl+0x19a/0x238 [<00000000c675f3f4>] __s390x_sys_ioctl+0xc4/0x100 [<00000000c63ca762>] do_syscall+0x82/0xd0 [<00000000c705bdd8>] __do_syscall+0xc0/0xd8 [<00000000c706d532>] system_call+0x72/0x98 2 locks held by psvc-readsets/7759: #0: 00000000c75a57c0 (cpu_hotplug_lock){++++}-{0:0}, at: cf_diag_ioctl+0x44/0x238 #1: 00000000c75a3078 (cf_diag_ctrset_mutex){+.+.}-{3:3}, at: cf_diag_ioctl+0x54/0x238 This issue is a missing get_cpu_ptr/put_cpu_ptr pair in function cf_diag_needspace. Add it. Fixes: cf6acb8bdb1d ("s390/cpumf: Add support for complete counter set extraction") Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-08s390/cpumf: remove unneeded semicolonJiapeng Chong1-1/+1
Fix the following coccicheck warnings: ./arch/s390/kernel/perf_cpum_cf.c:272:2-3: Unneeded semicolon. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/1614233736-87331-1-git-send-email-jiapeng.chong@linux.alibaba.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-08s390/cpumf: rename header file to hwctrset.hThomas Richter1-1/+1
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Suggested-by: Hendrick Brueckner <brueckner@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-08s390/cpumf: remove 60 seconds read limitThomas Richter1-16/+2
Remove the 60 seconds read interval limit. Do not impose any limit at all and allow read of complete counter sets. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-08s390/topology: remove always false if checkHeiko Carstens1-2/+0
The cpumask being checked in cpu_group_map() must have at least one cpu set; therefore remove the check. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-08s390/time,idle: get rid of unsigned long longHeiko Carstens2-20/+20
Get rid of unsigned long long, and use unsigned long instead everywhere. The usage of unsigned long long is a leftover from 31 bit kernel support. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-02-27Merge tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull io_uring thread rewrite from Jens Axboe: "This converts the io-wq workers to be forked off the tasks in question instead of being kernel threads that assume various bits of the original task identity. This kills > 400 lines of code from io_uring/io-wq, and it's the worst part of the code. We've had several bugs in this area, and the worry is always that we could be missing some pieces for file types doing unusual things (recent /dev/tty example comes to mind, userfaultfd reads installing file descriptors is another fun one... - both of which need special handling, and I bet it's not the last weird oddity we'll find). With these identical workers, we can have full confidence that we're never missing anything. That, in itself, is a huge win. Outside of that, it's also more efficient since we're not wasting space and code on tracking state, or switching between different states. I'm sure we're going to find little things to patch up after this series, but testing has been pretty thorough, from the usual regression suite to production. Any issue that may crop up should be manageable. There's also a nice series of further reductions we can do on top of this, but I wanted to get the meat of it out sooner rather than later. The general worry here isn't that it's fundamentally broken. Most of the little issues we've found over the last week have been related to just changes in how thread startup/exit is done, since that's the main difference between using kthreads and these kinds of threads. In fact, if all goes according to plan, I want to get this into the 5.10 and 5.11 stable branches as well. That said, the changes outside of io_uring/io-wq are: - arch setup, simple one-liner to each arch copy_thread() implementation. - Removal of net and proc restrictions for io_uring, they are no longer needed or useful" * tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits) io-wq: remove now unused IO_WQ_BIT_ERROR io_uring: fix SQPOLL thread handling over exec io-wq: improve manager/worker handling over exec io_uring: ensure SQPOLL startup is triggered before error shutdown io-wq: make buffered file write hashed work map per-ctx io-wq: fix race around io_worker grabbing io-wq: fix races around manager/worker creation and task exit io_uring: ensure io-wq context is always destroyed for tasks arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread() io_uring: cleanup ->user usage io-wq: remove nr_process accounting io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS net: remove cmsg restriction from io_uring based send/recvmsg calls Revert "proc: don't allow async path resolution of /proc/self components" Revert "proc: don't allow async path resolution of /proc/thread-self components" io_uring: move SQPOLL thread io-wq forked worker io-wq: make io_wq_fork_thread() available to other users io-wq: only remove worker from free_list, if it was there io_uring: remove io_identity io_uring: remove any grabbing of context ...
2021-02-26Merge tag 's390-5.12-2' of ↵Linus Torvalds3-43/+558
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Vasily Gorbik: - Fix physical vs virtual confusion in some basic mm macros and routines. Caused by __pa == __va on s390 currently. - Get rid of on-stack cpu masks. - Add support for complete CPU counter set extraction. - Add arch_irq_work_raise implementation. - virtio-ccw revision and opcode fixes. * tag 's390-5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/cpumf: Add support for complete counter set extraction virtio/s390: implement virtio-ccw revision 2 correctly s390/smp: implement arch_irq_work_raise() s390/topology: move cpumasks away from stack s390/smp: smp_emergency_stop() - move cpumask away from stack s390/smp: __smp_rescan_cpus() - move cpumask away from stack s390/smp: consolidate locking for smp_rescan() s390/mm: fix phys vs virt confusion in vmem_*() functions family s390/mm: fix phys vs virt confusion in pgtable allocation routines s390/mm: fix invalid __pa() usage in pfn_pXd() macros s390/mm: make pXd_deref() macros return a pointer s390/opcodes: rename selhhhr to selfhr
2021-02-24Merge tag 'x86-entry-2021-02-24' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 irq entry updates from Thomas Gleixner: "The irq stack switching was moved out of the ASM entry code in course of the entry code consolidation. It ended up being suboptimal in various ways. This reworks the X86 irq stack handling: - Make the stack switching inline so the stackpointer manipulation is not longer at an easy to find place. - Get rid of the unnecessary indirect call. - Avoid the double stack switching in interrupt return and reuse the interrupt stack for softirq handling. - A objtool fix for CONFIG_FRAME_POINTER=y builds where it got confused about the stack pointer manipulation" * tag 'x86-entry-2021-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Fix stack-swizzle for FRAME_POINTER=y um: Enforce the usage of asm-generic/softirq_stack.h x86/softirq/64: Inline do_softirq_own_stack() softirq: Move do_softirq_own_stack() to generic asm header softirq: Move __ARCH_HAS_DO_SOFTIRQ to Kconfig x86: Select CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK x86/softirq: Remove indirection in do_softirq_own_stack() x86/entry: Use run_sysvec_on_irqstack_cond() for XEN upcall x86/entry: Convert device interrupts to inline stack switching x86/entry: Convert system vectors to irq stack macro x86/irq: Provide macro for inlining irq stack switching x86/apic: Split out spurious handling code x86/irq/64: Adjust the per CPU irq stack pointer by 8 x86/irq: Sanitize irq stack tracking x86/entry: Fix instrumentation annotation
2021-02-24s390/cpumf: Add support for complete counter set extractionThomas Richter1-23/+525
Add support to the CPU Measurement counter facility device driver to extract complete counter sets per CPU and per counter set from user space. This includes a new device named /dev/hwctr and support for the device driver functions open, close and ioctl. Other functions are not supported. The ioctl command supports 3 subcommands: S390_HWCTR_START: enables counter sets on a list of CPUs. S390_HWCTR_STOP: disables counter sets on a list of CPUs. S390_HWCTR_READ: reads counter sets on a list of CPUs. The ioctl(..., S390_HWCTR_READ, ...) is the only subcommand which returns data. It requires member data_bytes to be positive and indicates the maximum amount of data available to store counter set data. The other ioctl() subcommands do not use this member and it should be set to zero. The S390_HWCTR_READ subcommand returns the following data: The cpuset data is flattened using the following scheme, stored in member data: 0x0 0x8 0xc 0x10 0x10 0x18 0x20 0x28 0xU-1 +---------+-----+---------+-----+---------+-----+-----+------+------+ | no_cpus | cpu | no_sets | set | no_cnts | cv1 | cv2 | .... | cv_n | +---------+-----+---------+-----+---------+-----+-----+------+------+ 0xU 0xU+4 0xU+8 0xU+10 0xV-1 +-----+---------+-----+-----+------+------+ | set | no_cnts | cv1 | cv2 | .... | cv_n | +-----+---------+-----+-----+------+------+ 0xV 0xV+4 0xV+8 0xV+c +-----+---------+-----+---------+-----+-----+------+------+ | cpu | no_sets | set | no_cnts | cv1 | cv2 | .... | cv_n | +-----+---------+-----+---------+-----+-----+------+------+ U and V denote arbitrary hexadezimal addresses. The first integer represents the number of CPUs data was extracted from. This is followed by CPU number and number of counter sets extracted. Both are two integer values. This is followed by the set identifer and number of counters extracted. Both are two integer values. This is followed by the counter values, each element is eight bytes in size. The S390_HWCTR_READ ioctl subcommand is also limited to one call per minute. This ensures that an application does not read out the counter sets too often and reduces the overall CPU performance. The complete counter set extraction is an expensive operation. Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-24s390/smp: implement arch_irq_work_raise()Ilya Leoshkevich1-0/+11
The immediate need to have this is to have bpf_send_signal() send the signal ASAP instead of during the next hrtimer interrupt. However, it should also improve irq_work_queue() latencies in general, as well as get s390 out of the lame architectures list [1]. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/kernel/irq_work.c?h=v5.11#n45 Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-24s390/topology: move cpumasks away from stackHeiko Carstens1-12/+13
Make cpumasks static variables to avoid potential large stack frames. There shouldn't be any concurrent callers since all current callers are serialized with the cpu hotplug lock. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-24s390/smp: smp_emergency_stop() - move cpumask away from stackHeiko Carstens1-1/+4
Make "cpumask_t cpumask" a static variable to avoid a potential large stack frame. Also protect against potential concurrent callers by introducing a local lock. Note: smp_emergency_stop() gets only called with irqs and machine checks disabled, therefore a cpu local deadlock is not possible. For concurrent callers the first cpu which enters the critical section wins and will stop all other cpus. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-24s390/smp: __smp_rescan_cpus() - move cpumask away from stackHeiko Carstens1-1/+1
Avoid a potentially large stack frame and overflow by making "cpumask_t avail" a static variable. There is no concurrent access due to the existing locking. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-24s390/smp: consolidate locking for smp_rescan()Heiko Carstens1-6/+4
Move locking to __smp_rescan() instead of duplicating it to all call sites. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-23Merge tag 'idmapped-mounts-v5.12' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull idmapped mounts from Christian Brauner: "This introduces idmapped mounts which has been in the making for some time. Simply put, different mounts can expose the same file or directory with different ownership. This initial implementation comes with ports for fat, ext4 and with Christoph's port for xfs with more filesystems being actively worked on by independent people and maintainers. Idmapping mounts handle a wide range of long standing use-cases. Here are just a few: - Idmapped mounts make it possible to easily share files between multiple users or multiple machines especially in complex scenarios. For example, idmapped mounts will be used in the implementation of portable home directories in systemd-homed.service(8) where they allow users to move their home directory to an external storage device and use it on multiple computers where they are assigned different uids and gids. This effectively makes it possible to assign random uids and gids at login time. - It is possible to share files from the host with unprivileged containers without having to change ownership permanently through chown(2). - It is possible to idmap a container's rootfs and without having to mangle every file. For example, Chromebooks use it to share the user's Download folder with their unprivileged containers in their Linux subsystem. - It is possible to share files between containers with non-overlapping idmappings. - Filesystem that lack a proper concept of ownership such as fat can use idmapped mounts to implement discretionary access (DAC) permission checking. - They allow users to efficiently changing ownership on a per-mount basis without having to (recursively) chown(2) all files. In contrast to chown (2) changing ownership of large sets of files is instantenous with idmapped mounts. This is especially useful when ownership of a whole root filesystem of a virtual machine or container is changed. With idmapped mounts a single syscall mount_setattr syscall will be sufficient to change the ownership of all files. - Idmapped mounts always take the current ownership into account as idmappings specify what a given uid or gid is supposed to be mapped to. This contrasts with the chown(2) syscall which cannot by itself take the current ownership of the files it changes into account. It simply changes the ownership to the specified uid and gid. This is especially problematic when recursively chown(2)ing a large set of files which is commong with the aforementioned portable home directory and container and vm scenario. - Idmapped mounts allow to change ownership locally, restricting it to specific mounts, and temporarily as the ownership changes only apply as long as the mount exists. Several userspace projects have either already put up patches and pull-requests for this feature or will do so should you decide to pull this: - systemd: In a wide variety of scenarios but especially right away in their implementation of portable home directories. https://systemd.io/HOME_DIRECTORY/ - container runtimes: containerd, runC, LXD:To share data between host and unprivileged containers, unprivileged and privileged containers, etc. The pull request for idmapped mounts support in containerd, the default Kubernetes runtime is already up for quite a while now: https://github.com/containerd/containerd/pull/4734 - The virtio-fs developers and several users have expressed interest in using this feature with virtual machines once virtio-fs is ported. - ChromeOS: Sharing host-directories with unprivileged containers. I've tightly synced with all those projects and all of those listed here have also expressed their need/desire for this feature on the mailing list. For more info on how people use this there's a bunch of talks about this too. Here's just two recent ones: https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf https://fosdem.org/2021/schedule/event/containers_idmap/ This comes with an extensive xfstests suite covering both ext4 and xfs: https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts It covers truncation, creation, opening, xattrs, vfscaps, setid execution, setgid inheritance and more both with idmapped and non-idmapped mounts. It already helped to discover an unrelated xfs setgid inheritance bug which has since been fixed in mainline. It will be sent for inclusion with the xfstests project should you decide to merge this. In order to support per-mount idmappings vfsmounts are marked with user namespaces. The idmapping of the user namespace will be used to map the ids of vfs objects when they are accessed through that mount. By default all vfsmounts are marked with the initial user namespace. The initial user namespace is used to indicate that a mount is not idmapped. All operations behave as before and this is verified in the testsuite. Based on prior discussions we want to attach the whole user namespace and not just a dedicated idmapping struct. This allows us to reuse all the helpers that already exist for dealing with idmappings instead of introducing a whole new range of helpers. In addition, if we decide in the future that we are confident enough to enable unprivileged users to setup idmapped mounts the permission checking can take into account whether the caller is privileged in the user namespace the mount is currently marked with. The user namespace the mount will be marked with can be specified by passing a file descriptor refering to the user namespace as an argument to the new mount_setattr() syscall together with the new MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern of extensibility. The following conditions must be met in order to create an idmapped mount: - The caller must currently have the CAP_SYS_ADMIN capability in the user namespace the underlying filesystem has been mounted in. - The underlying filesystem must support idmapped mounts. - The mount must not already be idmapped. This also implies that the idmapping of a mount cannot be altered once it has been idmapped. - The mount must be a detached/anonymous mount, i.e. it must have been created by calling open_tree() with the OPEN_TREE_CLONE flag and it must not already have been visible in the filesystem. The last two points guarantee easier semantics for userspace and the kernel and make the implementation significantly simpler. By default vfsmounts are marked with the initial user namespace and no behavioral or performance changes are observed. The manpage with a detailed description can be found here: https://git.kernel.org/brauner/man-pages/c/1d7b902e2875a1ff342e036a9f866a995640aea8 In order to support idmapped mounts, filesystems need to be changed and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The patches to convert individual filesystem are not very large or complicated overall as can be seen from the included fat, ext4, and xfs ports. Patches for other filesystems are actively worked on and will be sent out separately. The xfstestsuite can be used to verify that port has been done correctly. The mount_setattr() syscall is motivated independent of the idmapped mounts patches and it's been around since July 2019. One of the most valuable features of the new mount api is the ability to perform mounts based on file descriptors only. Together with the lookup restrictions available in the openat2() RESOLVE_* flag namespace which we added in v5.6 this is the first time we are close to hardened and race-free (e.g. symlinks) mounting and path resolution. While userspace has started porting to the new mount api to mount proper filesystems and create new bind-mounts it is currently not possible to change mount options of an already existing bind mount in the new mount api since the mount_setattr() syscall is missing. With the addition of the mount_setattr() syscall we remove this last restriction and userspace can now fully port to the new mount api, covering every use-case the old mount api could. We also add the crucial ability to recursively change mount options for a whole mount tree, both removing and adding mount options at the same time. This syscall has been requested multiple times by various people and projects. There is a simple tool available at https://github.com/brauner/mount-idmapped that allows to create idmapped mounts so people can play with this patch series. I'll add support for the regular mount binary should you decide to pull this in the following weeks: Here's an example to a simple idmapped mount of another user's home directory: u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt u1001@f2-vm:/$ ls -al /home/ubuntu/ total 28 drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 . drwxr-xr-x 4 root root 4096 Oct 28 04:00 .. -rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile -rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ ls -al /mnt/ total 28 drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 . drwxr-xr-x 29 root root 4096 Oct 28 22:01 .. -rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history -rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout -rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc -rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile -rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful -rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo u1001@f2-vm:/$ touch /mnt/my-file u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file u1001@f2-vm:/$ ls -al /mnt/my-file -rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file u1001@f2-vm:/$ ls -al /home/ubuntu/my-file -rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file u1001@f2-vm:/$ getfacl /mnt/my-file getfacl: Removing leading '/' from absolute path names # file: mnt/my-file # owner: u1001 # group: u1001 user::rw- user:u1001:rwx group::rw- mask::rwx other::r-- u1001@f2-vm:/$ getfacl /home/ubuntu/my-file getfacl: Removing leading '/' from absolute path names # file: home/ubuntu/my-file # owner: ubuntu # group: ubuntu user::rw- user:ubuntu:rwx group::rw- mask::rwx other::r--" * tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits) xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl xfs: support idmapped mounts ext4: support idmapped mounts fat: handle idmapped mounts tests: add mount_setattr() selftests fs: introduce MOUNT_ATTR_IDMAP fs: add mount_setattr() fs: add attr_flags_to_mnt_flags helper fs: split out functions to hold writers namespace: only take read lock in do_reconfigure_mnt() mount: make {lock,unlock}_mount_hash() static namespace: take lock_mount_hash() directly when changing flags nfs: do not export idmapped mounts overlayfs: do not mount on top of idmapped mounts ecryptfs: do not mount on top of idmapped mounts ima: handle idmapped mounts apparmor: handle idmapped mounts fs: make helpers idmap mount aware exec: handle idmapped mounts would_dump: handle idmapped mounts ...
2021-02-21arch: setup PF_IO_WORKER threads like PF_KTHREADJens Axboe1-1/+1
PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the sense that we don't assign ->set_child_tid with our own structure. Just ensure that every arch sets up the PF_IO_WORKER threads like kthreads in the arch implementation of copy_thread(). Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-21Merge tag 's390-5.12-1' of ↵Linus Torvalds26-1098/+763
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Convert to using the generic entry infrastructure. - Add vdso time namespace support. - Switch s390 and alpha to 64-bit ino_t. As discussed at https://lore.kernel.org/linux-mm/YCV7QiyoweJwvN+m@osiris/ - Get rid of expensive stck (store clock) usages where possible. Utilize cpu alternatives to patch stckf when supported. - Make tod_clock usage less error prone by converting it to a union and rework code which is using it. - Machine check handler fixes and cleanups. - Drop couple of minor inline asm optimizations to fix clang build. - Default configs changes notably to make libvirt happy. - Various changes to rework and improve qdio code. - Other small various fixes and improvements all over the code. * tag 's390-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (68 commits) s390/qdio: remove 'merge_pending' mechanism s390/qdio: improve handling of PENDING buffers for QEBSM devices s390/qdio: rework q->qdio_error indication s390/qdio: inline qdio_kick_handler() s390/time: remove get_tod_clock_ext() s390/crypto: use store_tod_clock_ext() s390/hypfs: use store_tod_clock_ext() s390/debug: use union tod_clock s390/kvm: use union tod_clock s390/vdso: use union tod_clock s390/time: convert tod_clock_base to union s390/time: introduce new store_tod_clock_ext() s390/time: rename store_tod_clock_ext() and use union tod_clock s390/time: introduce union tod_clock s390,alpha: switch to 64-bit ino_t s390: split cleanup_sie s390: use r13 in cleanup_sie as temp register s390: fix kernel asce loading when sie is interrupted s390: add stack for machine check handler s390: use WRITE_ONCE when re-allocating async stack ...
2021-02-21Merge branch 'work.elf-compat' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull ELF compat updates from Al Viro: "Sanitizing ELF compat support, especially for triarch architectures: - X32 handling cleaned up - MIPS64 uses compat_binfmt_elf.c both for O32 and N32 now - Kconfig side of things regularized Eventually I hope to have compat_binfmt_elf.c killed, with both native and compat built from fs/binfmt_elf.c, with -DELF_BITS={64,32} passed by kbuild, but that's a separate story - not included here" * 'work.elf-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: get rid of COMPAT_ELF_EXEC_PAGESIZE compat_binfmt_elf: don't bother with undef of ELF_ARCH Kconfig: regularize selection of CONFIG_BINFMT_ELF mips compat: switch to compat_binfmt_elf.c mips: don't bother with ELF_CORE_EFLAGS mips compat: don't bother with ELF_ET_DYN_BASE mips: KVM_GUEST makes no sense for 64bit builds... mips: kill unused definitions in binfmt_elf[on]32.c mips binfmt_elf*32.c: use elfcore-compat.h x32: make X32, !IA32_EMULATION setups able to execute x32 binaries [amd64] clean PRSTATUS_SIZE/SET_PR_FPVALID up properly elf_prstatus: collect the common part (everything before pr_reg) into a struct binfmt_elf: partially sanitize PRSTATUS_SIZE and SET_PR_FPVALID
2021-02-13s390/debug: use union tod_clockHeiko Carstens1-3/+3
Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390/vdso: use union tod_clockHeiko Carstens1-3/+3
Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390/time: convert tod_clock_base to unionHeiko Carstens4-38/+22
Convert tod_clock_base to union tod_clock. This simplifies quite a bit of code and also fixes a bug in read_persistent_clock64(); void read_persistent_clock64(struct timespec64 *ts) { __u64 delta; delta = initial_leap_seconds + TOD_UNIX_EPOCH; get_tod_clock_ext(clk); *(__u64 *) &clk[1] -= delta; if (*(__u64 *) &clk[1] > delta) clk[0]--; ext_to_timespec64(clk, ts); } Assume &clk[1] == 3 and delta == 2; then after the substraction the if condition becomes true and the epoch part of the clock is decremented by one because of an assumed overflow, even though there is none. Fix this by using 128 bit arithmetics and let the compiler do the right thing: void read_persistent_clock64(struct timespec64 *ts) { union tod_clock clk; u64 delta; delta = initial_leap_seconds + TOD_UNIX_EPOCH; store_tod_clock_ext(&clk); clk.eitod -= delta; ext_to_timespec64(&clk, ts); } Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390/time: rename store_tod_clock_ext() and use union tod_clockHeiko Carstens1-3/+3
Rename store_tod_clock_ext() to store_tod_clock_ext_cc() to reflect that it returns a condition code and also use union tod_clock as parameter. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390: split cleanup_sieSven Schnelle1-10/+7
The current code uses the address in %r11 to figure out whether it was called from the machine check handler or from a normal interrupt handler. Instead of doing this implicit logic (which is mostly a leftover from the old critical cleanup approach) just add a second label and use that. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390: use r13 in cleanup_sie as temp registerSven Schnelle1-2/+2
Instead of thrashing r11 which is normally our pointer to struct pt_regs on the stack, use r13 as temporary register in the BR_EX macro. r13 is already used in cleanup_sie, so no need to thrash another register. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390: fix kernel asce loading when sie is interruptedSven Schnelle1-2/+1
If a machine check is coming in during sie, the PU saves the control registers to the machine check save area. Afterwards mcck_int_handler is called, which loads __LC_KERNEL_ASCE into %cr1. Later the code restores %cr1 from the machine check area, but that is wrong when SIE was interrupted because the machine check area still contains the gmap asce. Instead it should return with either __KERNEL_ASCE in %cr1 when interrupted in SIE or the previous %cr1 content saved in the machine check save area. Fixes: 87d598634521 ("s390/mm: remove set_fs / rework address space handling") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Cc: <stable@kernel.org> # v5.8+ Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390: add stack for machine check handlerSven Schnelle4-18/+35
The previous code used the normal kernel stack for machine checks. This is problematic when a machine check interrupts a system call or interrupt handler right at the beginning where registers are set up. Assume system_call is interrupted at the first instruction and a machine check is triggered. The machine check handler is called, checks the PSW to see whether it is coming from user space, notices that it is already in kernel mode but %r15 still contains the user space stack. This would lead to a kernel crash. There are basically two ways of fixing that: Either using the 'critical cleanup' approach which compares the address in the PSW to see whether it is already at a point where the stack has been set up, or use an extra stack for the machine check handler. For simplicity, we will go with the second approach and allocate an extra stack. This adds some memory overhead for large systems, but usually large system have plenty of memory so this isn't really a concern. But it keeps the mchk stack setup simple and less error prone. Fixes: 0b0ed657fe00 ("s390: remove critical section cleanup from entry.S") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Cc: <stable@kernel.org> # v5.8+ Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390: use WRITE_ONCE when re-allocating async stackSven Schnelle1-1/+1
The code does: S390_lowcore.async_stack = new + STACK_INIT_OFFSET; But the compiler is free to first assign one value and add the other value later. If a IRQ would be coming in between these two operations, it would run with an invalid stack. Prevent this by using WRITE_ONCE. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-13s390: open code SWITCH_KERNEL macroSven Schnelle1-28/+46
This is a preparation patch for two later bugfixes. In the past both int_handler and machine check handler used SWITCH_KERNEL to switch to the kernel stack. However, SWITCH_KERNEL doesn't work properly in machine check context. So instead of adding more complexity to this macro, just remove it. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Cc: <stable@kernel.org> # v5.8+ Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-12Merge branch 'x86/paravirt' into x86/entryIngo Molnar1-1/+1
Merge in the recent paravirt changes to resolve conflicts caused by objtool annotations. Conflicts: arch/x86/xen/xen-asm.S Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-10softirq: Move do_softirq_own_stack() to generic asm headerThomas Gleixner1-0/+1
To avoid include recursion hell move the do_softirq_own_stack() related content into a generic asm header and include it from all places in arch/ which need the prototype. This allows architectures to provide an inline implementation of do_softirq_own_stack() without introducing a lot of #ifdeffery all over the place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002513.289960691@linutronix.de
2021-02-09s390/vtime: use cpu alternative for stck/stckfHeiko Carstens1-11/+8
Use a cpu alternative to switch between stck and stckf instead of making it compile time dependent. This will also make kernels compiled for old machines, but running on newer machines, use stckf. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/entry: use cpu alternative for stck/stckfHeiko Carstens1-5/+3
Use a cpu alternative to switch between stck and stckf instead of making it compile time dependent. This will also make kernels compiled for old machines, but running on newer machines, use stckf. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/time: use stcke instead of stckHeiko Carstens1-3/+3
Use STORE CLOCK EXTENDED instead of STORE CLOCK in early tod clock setup. This is just to remove another usage of stck, trying to remove all usages of STORE CLOCK. This doesn't fix anything. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/cpum_cf_diag: use get_tod_clock_fast()Heiko Carstens1-1/+1
Use get_tod_clock_fast() instead of store_tod_clock(), since store_tod_clock() can be very slow. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vtime: fix inline assembly clobber listHeiko Carstens1-1/+2
The stck/stckf instruction used within the inline assembly within do_account_vtime() changes the condition code. This is not reflected with the clobber list, and therefore might result in incorrect code generation. It seems unlikely that the compiler could generate incorrect code considering the surrounding C code, but it must still be fixed. Cc: <stable@vger.kernel.org> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: on timens page fault prefault also VVAR pageHeiko Carstens1-4/+13
This is the s390 variant of commit e6b28ec65b6d ("x86/vdso: On timens page fault prefault also VVAR page"). Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: implement generic vdso time namespace supportHeiko Carstens2-8/+99
Implement generic vdso time namespace support which also enables time namespaces for s390. This is quite similar to what arm64 has. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: move data page before code pagesHeiko Carstens2-17/+15
For consistency with x86 and arm64 move the data page before code pages. Similar to commit 601255ae3c98 ("arm64: vdso: move data page before code pages"). Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: put vdso datapage in a separate vmaHeiko Carstens1-20/+35
Add a separate "[vvar]" mapping for the vdso datapage, since it doesn't need to be executable or COW-able. This is actually the s390 implementation of commit 871549385278 ("arm64: vdso: put vdso datapage in a separate vma") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: get rid of vdso_faultHeiko Carstens1-26/+9
Implement vdso mapping similar to arm64 and powerpc. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: misc simple code changesHeiko Carstens1-72/+30
- remove unneeded includes - move functions around - remove obvious and/or incorrect comments - shorten some if conditions No functional change. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: remove superfluous variablesHeiko Carstens1-22/+13
A few local variables exist only so the contents of a global variable can be copied to them, and use that value only for reading. Just remove them and rename some global variables. Also change vdso64_[start|end] to be character arrays to be consistent with other architectures, and get rid of the global variable vdso64_kbase. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: remove superfluous checkHeiko Carstens1-7/+0
vdso_pages (aka vdso64_pages) is never 0, therefore remove the check. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: remove BUG_ON()Heiko Carstens1-1/+4
Handle allocation error gracefully and simply disable vdso instead of leaving the system in an undefined state. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: simplify vdso size calculationHeiko Carstens1-2/+1
The vdso is (and must) be page aligned and its size must also be a multiple of PAGE_SIZE. Therefore no need to round upwards. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: convert vdso_init() to arch_initcallHeiko Carstens1-3/+4
Convert vdso_init() to arch_initcall like it is on all other architectures. This requires to remove the vdso_getcpu_init() call from vdso_init() since it must be called before smp is enabled. vdso_getcpu_init() is now an early_initcall like on powerpc. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-09s390/vdso: fix vdso data page definitionHeiko Carstens1-2/+2
The vdso data page actually contains an array. Fix that. This doesn't fix a real bug, just reflects reality. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-01-27s390: add missing include to arch/s390/kernel/signal.cSven Schnelle1-0/+1
This fixes the following warning: CHECK linux/arch/s390/kernel/signal.c linux/arch/s390/kernel/signal.c:465:6: warning: symbol 'arch_do_signal_or_restart' was not declared. Should it be static? Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>