kernel.git/arch/csky/kernel, branch linux-5.19.y

csky/kprobe: reclaim insn_slot on kprobe unregistration

2022-08-25T09:45:46Z

[ Upstream commit a2310c74d418deca0f1d749c45f1f43162510f51 ] On kprobe registration kernel allocate one insn_slot for new kprobe, but it forget to reclaim the insn_slot on unregistration, leading to a potential leakage. Reported-by: Chen Guokai Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Liao Chang Signed-off-by: Guo Ren Signed-off-by: Sasha Levin

Merge tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2022-06-03T23:03:05Z

Pull kthread updates from Eric Biederman: "This updates init and user mode helper tasks to be ordinary user mode tasks. Commit 40966e316f86 ("kthread: Ensure struct kthread is present for all kthreads") caused init and the user mode helper threads that call kernel_execve to have struct kthread allocated for them. This struct kthread going away during execve in turned made a use after free of struct kthread possible. Here, commit 343f4c49f243 ("kthread: Don't allocate kthread_struct for init and umh") is enough to fix the use after free and is simple enough to be backportable. The rest of the changes pass struct kernel_clone_args to clean things up and cause the code to make sense. In making init and the user mode helpers tasks purely user mode tasks I ran into two complications. The function task_tick_numa was detecting tasks without an mm by testing for the presence of PF_KTHREAD. The initramfs code in populate_initrd_image was using flush_delayed_fput to ensuere the closing of all it's file descriptors was complete, and flush_delayed_fput does not work in a userspace thread. I have looked and looked and more complications and in my code review I have not found any, and neither has anyone else with the code sitting in linux-next" * tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: sched: Update task_tick_numa to ignore tasks without an mm fork: Stop allowing kthreads to call execve fork: Explicitly set PF_KTHREAD init: Deal with the init process being a user mode process fork: Generalize PF_IO_WORKER handling fork: Explicity test for idle tasks in copy_thread fork: Pass struct kernel_clone_args into copy_thread kthread: Don't allocate kthread_struct for init and umh

Merge back reboot/poweroff notifiers rework for 5.19-rc1.

2022-05-25T12:38:29Z

csky: Use do_kernel_power_off()

2022-05-19T17:30:30Z

Kernel now supports chained power-off handlers. Use do_kernel_power_off() that invokes chained power-off handlers. It also invokes legacy pm_power_off() for now, which will be removed once all drivers will be converted to the new sys-off API. Acked-by: Guo Ren Reviewed-by: Michał Mirosław Signed-off-by: Dmitry Osipenko Signed-off-by: Rafael J. Wysocki

fork: Generalize PF_IO_WORKER handling

2022-05-07T14:01:59Z

Add fn and fn_arg members into struct kernel_clone_args and test for them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER). This allows any task that wants to be a user space task that only runs in kernel mode to use this functionality. The code on x86 is an exception and still retains a PF_KTHREAD test because x86 unlikely everything else handles kthreads slightly differently than user space tasks that start with a function. The functions that created tasks that start with a function have been updated to set ".fn" and ".fn_arg" instead of ".stack" and ".stack_size". These functions are fork_idle(), create_io_thread(), kernel_thread(), and user_mode_thread(). Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman"

fork: Pass struct kernel_clone_args into copy_thread

2022-05-07T14:01:48Z

With io_uring we have started supporting tasks that are for most purposes user space tasks that exclusively run code in kernel mode. The kernel task that exec's init and tasks that exec user mode helpers are also user mode tasks that just run kernel code until they call kernel execve. Pass kernel_clone_args into copy_thread so these oddball tasks can be supported more cleanly and easily. v2: Fix spelling of kenrel_clone_args on h8300 Link: https://lkml.kernel.org/r/20220506141512.516114-2-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman"

csky: optimize memcpy_{from,to}io() and memset_io()

2022-04-18T13:23:55Z

Optimize memcpy_{from,to}io() and memset_io() by transferring in 64 bit as much as possible with minimized barrier usage. This simplest optimization brings faster throughput compare to current byte-by-byte read and write with barrier in the loop. Code's skeleton is taken from the powerpc & arm64. Signed-off-by: Guo Ren Signed-off-by: Guo Ren

csky: Fix versioncheck warnings

2022-04-08T07:05:23Z

$make versioncheck arch/csky/include/asm/io.h: 8 linux/version.h not needed. arch/csky/kernel/process.c: 5 linux/version.h not needed. arch/csky/mm/dma-mapping.c: 12 linux/version.h not needed. comments from Randy: The patch makes sense but these are not compile warnings. They come from scripts/checkversion.pl, which can be called by 'make versioncheck', so I suppose that something in your build system is running 'make versioncheck'. Signed-off-by: Deyan Wang Acked-by: Randy Dunlap Signed-off-by: Guo Ren Signed-off-by: Guo Ren

csky: patch_text: Fixup last cpu should be master

2022-04-07T07:35:57Z

These patch_text implementations are using stop_machine_cpuslocked infrastructure with atomic cpu_count. The original idea: When the master CPU patch_text, the others should wait for it. But current implementation is using the first CPU as master, which couldn't guarantee the remaining CPUs are waiting. This patch changes the last CPU as the master to solve the potential risk. Fixes: 33e53ae1ce41 ("csky: Add kprobes supported") Signed-off-by: Guo Ren Signed-off-by: Guo Ren Reviewed-by: Masami Hiramatsu Cc:

csky: fix typos in comments

2022-04-06T14:37:58Z

Various spelling mistakes in comments. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall Signed-off-by: Guo Ren