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2022-05-23xtensa: Return true/false (not 1/0) from bool functionYang Li1-1/+1
Return boolean values ("true" or "false") instead of 1 or 0 from bool function. This fixes the following warnings from coccicheck: ./arch/xtensa/kernel/traps.c:304:10-11: WARNING: return of 0/1 in function 'check_div0' with return type bool Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Message-Id: <20220518230953.112266-1-yang.lee@linux.alibaba.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-17xtensa: improve call0 ABI probingMax Filippov3-0/+20
When call0 userspace ABI support by probing is enabled instructions that cause illegal instruction exception when PS.WOE is clear are retried with PS.WOE set before calling c-level exception handler. Record user pc at which PS.WOE was set in the fast exception handler and clear PS.WOE in the c-level exception handler if we get there from the same address. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-17xtensa: support artificial division by 0 exceptionMax Filippov1-0/+23
On xtensa cores wihout hardware division option division support functions from libgcc react to division by 0 attempt by executing illegal instruction followed by the characters 'DIV0'. Recognize this pattern in illegal instruction exception handler and convert it to division by 0. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-13xtensa: add trap handler for division by zeroMax Filippov1-1/+7
Add c-level handler for the division by zero exception and kill the task if it was thrown from the kernel space or send SIGFPE otherwise. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: clean up labels in the kernel entry assemblyMax Filippov1-47/+53
Don't use numeric labels for long jumps, use named local labels instead. Avoid conditional label definition. No functional changes. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: don't leave invalid TLB entry in fast_store_prohibitedMax Filippov1-1/+5
When fast_store_prohibited needs to go to the C-level exception handler it leaves TLB entry that caused page fault in the TLB. If the faulting task gets switched to a different CPU and completes page table update there the TLB entry will get out of sync with the page table which may cause a livelock on access to that page. Invalidate faulting TLB entry on a slow path exit from the fast_store_prohibited. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: add hibernation supportMax Filippov4-0/+126
Define ARCH_HIBERNATION_POSSIBLE in Kconfig and implement hibernation callbacks. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: support coprocessors on SMPMax Filippov8-65/+215
Current coprocessor support on xtensa only works correctly on uniprocessor configurations. Make it work on SMP too and keep it lazy. Make coprocessor_owner array per-CPU and move it to struct exc_table for easy access from the fast_coprocessor exception handler. Allow task to have live coprocessors only on single CPU, record this CPU number in the struct thread_info::cp_owner_cpu. Change struct thread_info::cpenable meaning to be 'coprocessors live on cp_owner_cpu'. Introduce C-level coprocessor exception handler that flushes and releases live coprocessors of the task taking 'coprocessor disabled' exception and call it from the fast_coprocessor handler when the task has live coprocessors on other CPU. Make coprocessor_flush_all and coprocessor_release_all work correctly when called from any CPU by sending IPI to the cp_owner_cpu. Add function coprocessor_flush_release_all to do flush followed by release atomically. Add function local_coprocessors_flush_release_all to flush and release all coprocessors on the local CPU and use it to flush coprocessor contexts from the CPU that goes offline. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: get rid of stack frame in coprocessor_flushMax Filippov1-6/+5
coprocessor_flush is an ordinary function, it can use all registers. Don't reserve stack frame for it and use a7 to preserve a0 around the context saving call. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: merge SAVE_CP_REGS_TAB and LOAD_CP_REGS_TABMax Filippov1-48/+37
Both tables share the same offset field but the different function pointers. Merge them into single table with 3-element entries to reduce code and data duplication. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: handle coprocessor exceptions in kernel modeMax Filippov1-1/+1
In order to let drivers use xtensa coprocessors on behalf of the calling process the kernel must handle coprocessor exceptions from the kernel mode the same way as from the user mode. This is not sufficient to allow using coprocessors transparently in IRQ or softirq context. Should such users exist they must be aware of the context and do the right thing, e.g. preserve the coprocessor state and resore it after use. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: use callx0 opcode in fast_coprocessorMax Filippov1-10/+8
Instead of emulating call0 in fast_coprocessor use that opcode directly. Use 'ret' instead of 'jx a0'. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: clean up excsave1 initializationMax Filippov1-2/+1
Use xtensa_set_sr instead of inline assembly. Rename local variable exc_table in early_trap_init to avoid conflict with per-CPU variable of the same name. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: clean up exception handler prototypesMax Filippov2-7/+7
Exception handlers are currently passed as void pointers because they may have one or two parameters. Only two handlers uses the second parameter and it is available in the struct pt_regs anyway. Make all handlers have only one parameter, introduce xtensa_exception_handler type for handlers and use it in trap_set_handler. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: clean up function declarations in traps.cMax Filippov1-30/+16
Drop 'extern' from all function declarations and move those that need to be visible from traps.c to traps.h. Add 'asmlinkage' to declarations of fucntions defined in assembly. Add 'static' to declarations and definitions only used locally. Add argument names in declarations. Drop unused second argument from do_multihit and do_page_fault. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: enable context trackingMax Filippov1-0/+9
Put user exit context tracking call on the common kernel entry/exit path (function calls are impossible at earlier kernel entry stages because PS.EXCM is not cleared yet). Put user entry context tracking call on the user exit path. Syscalls go through this common code too, so nothing specific needs to be done for them. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: use abi_* register names in the kernel exit codeMax Filippov1-40/+42
Using plain register names is prone to errors when code is changed and new calls are added between the register load and use. Change plain register names to abi_* names in the call-heavy part of the kernel exit code to clearly indicate what's supposed to be preserved and what's not. Re-align code while at it. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: move trace_hardirqs_off call back to entry.SMax Filippov2-15/+15
Context tracking call must be done after hardirq tracking call, otherwise lockdep_assert_irqs_disabled called from rcu_eqs_exit gives a warning. To avoid context tracking logic duplication for IRQ/exception entry paths move trace_hardirqs_off call back to common entry code. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: drop dead code from entry.SMax Filippov1-18/+0
KERNEL_STACK_OVERFLOW_CHECK is incomplete and have never been enabled. Remove it. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: noMMU: allow handling protection faultsMax Filippov1-10/+10
Many xtensa CPU cores without full MMU still have memory protection features capable of raising exceptions for invalid instruction fetches/data access. Allow handling such exceptions. This improves behavior of processes that pass invalid memory pointers to syscalls in noMMU configs: in case of exception the kernel instead of killing the process is now able to return -EINVAL from a syscall. Introduce CONFIG_PFAULT that controls whether protection fault code is enabled and register handlers for common memory protection exceptions when it is enabled. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-04-15xtensa: fix a7 clobbering in coprocessor context load/storeMax Filippov1-2/+2
Fast coprocessor exception handler saves a3..a6, but coprocessor context load/store code uses a4..a7 as temporaries, potentially clobbering a7. 'Potentially' because coprocessor state load/store macros may not use all four temporary registers (and neither FPU nor HiFi macros do). Use a3..a6 as intended. Cc: stable@vger.kernel.org Fixes: c658eac628aa ("[XTENSA] Add support for configurable registers and coprocessors") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-04-13xtensa: patch_text: Fixup last cpu should be masterGuo Ren1-1/+1
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: 64711f9a47d4 ("xtensa: implement jump_label support") Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Reviewed-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: <stable@vger.kernel.org> Message-Id: <20220407073323.743224-4-guoren@kernel.org> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-31Merge tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuildLinus Torvalds1-2/+1
Pull Kbuild updates from Masahiro Yamada: - Add new environment variables, USERCFLAGS and USERLDFLAGS to allow additional flags to be passed to user-space programs. - Fix missing fflush() bugs in Kconfig and fixdep - Fix a minor bug in the comment format of the .config file - Make kallsyms ignore llvm's local labels, .L* - Fix UAPI compile-test for cross-compiling with Clang - Extend the LLVM= syntax to support LLVM=<suffix> form for using a particular version of LLVm, and LLVM=<prefix> form for using custom LLVM in a particular directory path. - Clean up Makefiles * tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: Make $(LLVM) more flexible kbuild: add --target to correctly cross-compile UAPI headers with Clang fixdep: use fflush() and ferror() to ensure successful write to files arch: syscalls: simplify uapi/kapi directory creation usr/include: replace extra-y with always-y certs: simplify empty certs creation in certs/Makefile certs: include certs/signing_key.x509 unconditionally kallsyms: ignore all local labels prefixed by '.L' kconfig: fix missing '# end of' for empty menu kconfig: add fflush() before ferror() check kbuild: replace $(if A,A,B) with $(or A,B) kbuild: Add environment variables for userprogs flags kbuild: unify cmd_copy and cmd_shipped
2022-03-31arch: syscalls: simplify uapi/kapi directory creationMasahiro Yamada1-2/+1
$(shell ...) expands to empty. There is no need to assign it to _dummy. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2022-03-28Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds2-5/+4
Pull ptrace cleanups from Eric Biederman: "This set of changes removes tracehook.h, moves modification of all of the ptrace fields inside of siglock to remove races, adds a missing permission check to ptrace.c The removal of tracehook.h is quite significant as it has been a major source of confusion in recent years. Much of that confusion was around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the semantics clearer). For people who don't know tracehook.h is a vestiage of an attempt to implement uprobes like functionality that was never fully merged, and was later superseeded by uprobes when uprobes was merged. For many years now we have been removing what tracehook functionaly a little bit at a time. To the point where anything left in tracehook.h was some weird strange thing that was difficult to understand" * tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: ptrace: Remove duplicated include in ptrace.c ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE ptrace: Return the signal to continue with from ptrace_stop ptrace: Move setting/clearing ptrace_message into ptrace_stop tracehook: Remove tracehook.h resume_user_mode: Move to resume_user_mode.h resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume signal: Move set_notify_signal and clear_notify_signal into sched/signal.h task_work: Decouple TIF_NOTIFY_SIGNAL and task_work task_work: Call tracehook_notify_signal from get_signal on all architectures task_work: Introduce task_work_pending task_work: Remove unnecessary include from posix_timers.h ptrace: Remove tracehook_signal_handler ptrace: Remove arch_syscall_{enter,exit}_tracehook ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h ptrace/arm: Rename tracehook_report_syscall report_syscall ptrace: Move ptrace_report_syscall into ptrace.h
2022-03-25Merge tag 'xtensa-20220325' of https://github.com/jcmvbkbc/linux-xtensaLinus Torvalds10-76/+50
Pull Xtensa updates from Max Filippov: - remove dependency on the compiler's libgcc - allow selection of internal kernel ABI via Kconfig - enable compiler plugins support for gcc-12 or newer - various minor cleanups and fixes * tag 'xtensa-20220325' of https://github.com/jcmvbkbc/linux-xtensa: xtensa: define update_mmu_tlb function xtensa: fix xtensa_wsr always writing 0 xtensa: enable plugin support xtensa: clean up kernel exit assembly code xtensa: rearrange NMI exit path xtensa: merge stack alignment definitions xtensa: fix DTC warning unit_address_format xtensa: fix stop_machine_cpuslocked call in patch_text xtensa: make secondary reset vector support conditional xtensa: add kernel ABI selection to Kconfig xtensa: don't link with libgcc xtensa: add helpers for division, remainder and shifts xtensa: add missing XCHAL_HAVE_WINDOWED check xtensa: use XCHAL_NUM_AREGS as pt_regs::areg size xtensa: rename PT_SIZE to PT_KERNEL_SIZE xtensa: Remove unused early_read_config_byte() et al declarations xtensa: use strscpy to copy strings net: xtensa: use strscpy to copy strings
2022-03-23Merge tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-genericLinus Torvalds1-3/+0
Pull asm-generic updates from Arnd Bergmann: "There are three sets of updates for 5.18 in the asm-generic tree: - The set_fs()/get_fs() infrastructure gets removed for good. This was already gone from all major architectures, but now we can finally remove it everywhere, which loses some particularly tricky and error-prone code. There is a small merge conflict against a parisc cleanup, the solution is to use their new version. - The nds32 architecture ends its tenure in the Linux kernel. The hardware is still used and the code is in reasonable shape, but the mainline port is not actively maintained any more, as all remaining users are thought to run vendor kernels that would never be updated to a future release. - A series from Masahiro Yamada cleans up some of the uapi header files to pass the compile-time checks" * tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits) nds32: Remove the architecture uaccess: remove CONFIG_SET_FS ia64: remove CONFIG_SET_FS support sh: remove CONFIG_SET_FS support sparc64: remove CONFIG_SET_FS support lib/test_lockup: fix kernel pointer check for separate address spaces uaccess: generalize access_ok() uaccess: fix type mismatch warnings from access_ok() arm64: simplify access_ok() m68k: fix access_ok for coldfire MIPS: use simpler access_ok() MIPS: Handle address errors for accesses above CPU max virtual user address uaccess: add generic __{get,put}_kernel_nofault nios2: drop access_ok() check from __put_user() x86: use more conventional access_ok() definition x86: remove __range_not_ok() sparc64: add __{get,put}_kernel_nofault() nds32: fix access_ok() checks in get/put_user uaccess: fix nios2 and microblaze get_user_8() sparc64: fix building assembly files ...
2022-03-19xtensa: clean up kernel exit assembly codeMax Filippov1-25/+25
Don't use numeric labels for complex branching logic. Mark each branch with named local label and use them. Rearrange exit back to kernel mode to avoid conditional label definition. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-19xtensa: rearrange NMI exit pathMax Filippov1-9/+4
NMI exit path to userspace should neither check TIF_DB_DISABLED nor call check_tlb_sanity because NMI shouldn't touch anything related to userspace. Drop kernel/userspace check in NMI exit path. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-16xtensa: fix stop_machine_cpuslocked call in patch_textMax Filippov1-1/+1
patch_text must invoke patch_text_stop_machine on all online CPUs, but it calls stop_machine_cpuslocked with NULL cpumask. As a result only one CPU runs patch_text_stop_machine potentially leaving stale icache entries on other CPUs. Fix that by calling stop_machine_cpuslocked with cpu_online_mask as the last argument. Cc: stable@vger.kernel.org Fixes: 64711f9a47d4 ("xtensa: implement jump_label support") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-10resume_user_mode: Move to resume_user_mode.hEric W. Biederman1-2/+2
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h. While doing that rename tracehook_notify_resume to resume_user_mode_work. Update all of the places that included tracehook.h for these functions to include resume_user_mode.h instead. Update all of the callers of tracehook_notify_resume to call resume_user_mode_work. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-10ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.hEric W. Biederman1-3/+2
Rename tracehook_report_syscall_{entry,exit} to ptrace_report_syscall_{entry,exit} and place them in ptrace.h There is no longer any generic tracehook infractructure so make these ptrace specific functions ptrace specific. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-3-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-09xtensa: make secondary reset vector support conditionalMax Filippov3-4/+5
Whether xtensa cores start from primary or secondary reset vector is configurable and may be chosen by board designer or controlled at runtime. When secondary reset vector is unused its location in memory may not be writable. Make secondary reset vector support conditional and don't build and load secondary reset vector code when it is disabled. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-09xtensa: don't link with libgccMax Filippov1-14/+0
libgcc may be absent or may have different ABI than the kernel. Don't link with it. Drop declarations and export for helpers that are not implemented. Use generic versions of DI mode multiplication and comparisons. Drop register window spilling helper as it should never be used by the compiler-generated code. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-09xtensa: add missing XCHAL_HAVE_WINDOWED checkMax Filippov1-0/+2
Add missing preprocessor conditions to secondary reset vector code. Fixes: 09af39f649da ("xtensa: use register window specific opcodes only when present") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-07xtensa: use XCHAL_NUM_AREGS as pt_regs::areg sizeMax Filippov1-10/+0
struct pt_regs is used to access both kernel and user exception frames. User exception frames may contain up to XCHAL_NUM_AREG registers that task creation and signal delivery code may access, but pt_regs::areg array has only 16 entries that cover only the kernel exception frame. This results in the following build error: arch/xtensa/kernel/process.c: In function 'copy_thread': arch/xtensa/kernel/process.c:262:52: error: array subscript 53 is above array bounds of 'long unsigned int[16]' [-Werror=array-bounds] 262 | put_user(regs->areg[caller_ars+1], Change struct pt_regs::areg size to XCHAL_NUM_AREGS so that it covers the whole user exception frame. Adjust task_pt_regs and drop additional register copying code from copy_thread now that the whole user exception stack frame is copied. Reported-by: Kees Cook <keescook@chromium.org> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org>
2022-03-07xtensa: rename PT_SIZE to PT_KERNEL_SIZEMax Filippov3-10/+10
PT_SIZE is used by the xtensa port to designate kernel exception frame size. In preparation for struct pt_regs size change rename PT_SIZE to PT_KERNEL_SIZE for clarity and change its definition to always cover only the kernel exception frame. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org>
2022-03-06xtensa: use strscpy to copy stringsJason Wang1-4/+4
The strlcpy should not be used because it doesn't limit the source length. So that it will lead some potential bugs. But the strscpy doesn't require reading memory from the src string beyond the specified "count" bytes, and since the return value is easier to error-check than strlcpy()'s. In addition, the implementation is robust to the string changing out from underneath it, unlike the current strlcpy() implementation. Thus, replace strlcpy with strscpy. Signed-off-by: Jason Wang <wangborong@cdjrlc.com> Message-Id: <20211220084756.955307-1-wangborong@cdjrlc.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-02-25xtensa: Implement "current_stack_pointer"Kees Cook1-2/+1
To follow the existing per-arch conventions replace open-coded uses of asm "sp" as "current_stack_pointer". This will let it be used in non-arch places (like HARDENED_USERCOPY). Cc: Chris Zankel <chris@zankel.net> Cc: Marc Zyngier <maz@kernel.org> Cc: linux-xtensa@linux-xtensa.org Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Link: https://lore.kernel.org/lkml/CAMo8BfJFJE-n3=AF+pb9_6oF3gzxX7a+7aBrASHjjNX5byqDqw@mail.gmail.com
2022-02-25uaccess: remove CONFIG_SET_FSArnd Bergmann1-3/+0
There are no remaining callers of set_fs(), so CONFIG_SET_FS can be removed globally, along with the thread_info field and any references to it. This turns access_ok() into a cheaper check against TASK_SIZE_MAX. As CONFIG_SET_FS is now gone, drop all remaining references to set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel(). Acked-by: Sam Ravnborg <sam@ravnborg.org> # for sparc32 changes Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Tested-by: Sergey Matyukevich <sergey.matyukevich@synopsys.com> # for arc changes Acked-by: Stafford Horne <shorne@gmail.com> # [openrisc, asm-generic] Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-01-17Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds2-2/+2
Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc/<pid>/stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...
2022-01-15mm/mempolicy: wire up syscall set_mempolicy_home_nodeAneesh Kumar K.V1-0/+1
Link: https://lkml.kernel.org/r/20211202123810.267175-4-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Ben Widawsky <ben.widawsky@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: <linux-api@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-08exit/xtensa: In arch/xtensa/entry.S:Linvalid_mask call make_task_deadEric W. Biederman1-1/+1
There have historically been two big uses of do_exit. The first is it's design use to be the guts of the exit(2) system call. The second use is to terminate a task after something catastrophic has happened like a NULL pointer in kernel code. The function make_task_dead has been added to accomidate the second use. The call to do_exit in Linvalidmask is clearly not a normal userspace exit. As failure handling there are two possible ways to go. If userspace can trigger the issue force_exit_sig should be called. Otherwise make_task_dead probably from the implementation of die is appropriate. Replace the call of do_exit in Linvalidmask with make_task_dead as I don't know xtensa and especially xtensa assembly language well enough to do anything else. Link: https://lkml.kernel.org/r/YdUmN7n4W5YETUhW@zeniv-ca.linux.org.uk Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-12-13exit: Add and use make_task_dead.Eric W. Biederman1-1/+1
There are two big uses of do_exit. The first is it's design use to be the guts of the exit(2) system call. The second use is to terminate a task after something catastrophic has happened like a NULL pointer in kernel code. Add a function make_task_dead that is initialy exactly the same as do_exit to cover the cases where do_exit is called to handle catastrophic failure. In time this can probably be reduced to just a light wrapper around do_task_dead. For now keep it exactly the same so that there will be no behavioral differences introducing this new concept. Replace all of the uses of do_exit that use it for catastraphic task cleanup with make_task_dead to make it clear what the code is doing. As part of this rename rewind_stack_do_exit rewind_stack_and_make_dead. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-11-25futex: Wireup futex_waitv syscallAndré Almeida1-0/+1
Wireup futex_waitv syscall for all remaining archs. Signed-off-by: André Almeida <andrealmeid@collabora.com> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2021-11-10Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds1-1/+1
Pull exit cleanups from Eric Biederman: "While looking at some issues related to the exit path in the kernel I found several instances where the code is not using the existing abstractions properly. This set of changes introduces force_fatal_sig a way of sending a signal and not allowing it to be caught, and corrects the misuse of the existing abstractions that I found. A lot of the misuse of the existing abstractions are silly things such as doing something after calling a no return function, rolling BUG by hand, doing more work than necessary to terminate a kernel thread, or calling do_exit(SIGKILL) instead of calling force_sig(SIGKILL). In the review a deficiency in force_fatal_sig and force_sig_seccomp where ptrace or sigaction could prevent the delivery of the signal was found. I have added a change that adds SA_IMMUTABLE to change that makes it impossible to interrupt the delivery of those signals, and allows backporting to fix force_sig_seccomp And Arnd found an issue where a function passed to kthread_run had the wrong prototype, and after my cleanup was failing to build." * 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (23 commits) soc: ti: fix wkup_m3_rproc_boot_thread return type signal: Add SA_IMMUTABLE to ensure forced siganls do not get changed signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV) exit/r8188eu: Replace the macro thread_exit with a simple return 0 exit/rtl8712: Replace the macro thread_exit with a simple return 0 exit/rtl8723bs: Replace the macro thread_exit with a simple return 0 signal/x86: In emulate_vsyscall force a signal instead of calling do_exit signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig signal/sparc32: Exit with a fatal signal when try_to_clear_window_buffer fails exit/syscall_user_dispatch: Send ordinary signals on failure signal: Implement force_fatal_sig exit/kthread: Have kernel threads return instead of calling do_exit signal/s390: Use force_sigsegv in default_trap_handler signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved. signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON signal/sparc: In setup_tsb_params convert open coded BUG into BUG signal/powerpc: On swapcontext failure force SIGSEGV signal/sh: Use force_sig(SIGKILL) instead of do_group_exit(SIGKILL) signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT signal/sparc32: Remove unreachable do_exit in do_sparc_fault ...
2021-11-06Merge tag 'xtensa-20211105' of git://github.com/jcmvbkbc/linux-xtensaLinus Torvalds10-189/+305
Pull xtensa updates from Max Filippov: - add support for xtensa cores without windowed registers option * tag 'xtensa-20211105' of git://github.com/jcmvbkbc/linux-xtensa: xtensa: move section symbols to asm/sections.h xtensa: remove unused variable wmask xtensa: only build windowed register support code when needed xtensa: use register window specific opcodes only when present xtensa: implement call0 ABI support in assembly xtensa: definitions for call0 ABI xtensa: don't use a12 in __xtensa_copy_user in call0 ABI xtensa: don't use a12 in strncpy_user xtensa: use a14 instead of a15 in inline assembly xtensa: move _SimulateUserKernelVectorException out of WindowVectors
2021-11-01Merge tag 'sched-core-2021-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-4/+1
Pull scheduler updates from Thomas Gleixner: - Revert the printk format based wchan() symbol resolution as it can leak the raw value in case that the symbol is not resolvable. - Make wchan() more robust and work with all kind of unwinders by enforcing that the task stays blocked while unwinding is in progress. - Prevent sched_fork() from accessing an invalid sched_task_group - Improve asymmetric packing logic - Extend scheduler statistics to RT and DL scheduling classes and add statistics for bandwith burst to the SCHED_FAIR class. - Properly account SCHED_IDLE entities - Prevent a potential deadlock when initial priority is assigned to a newly created kthread. A recent change to plug a race between cpuset and __sched_setscheduler() introduced a new lock dependency which is now triggered. Break the lock dependency chain by moving the priority assignment to the thread function. - Fix the idle time reporting in /proc/uptime for NOHZ enabled systems. - Improve idle balancing in general and especially for NOHZ enabled systems. - Provide proper interfaces for live patching so it does not have to fiddle with scheduler internals. - Add cluster aware scheduling support. - A small set of tweaks for RT (irqwork, wait_task_inactive(), various scheduler options and delaying mmdrop) - The usual small tweaks and improvements all over the place * tag 'sched-core-2021-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits) sched/fair: Cleanup newidle_balance sched/fair: Remove sysctl_sched_migration_cost condition sched/fair: Wait before decaying max_newidle_lb_cost sched/fair: Skip update_blocked_averages if we are defering load balance sched/fair: Account update_blocked_averages in newidle_balance cost x86: Fix __get_wchan() for !STACKTRACE sched,x86: Fix L2 cache mask sched/core: Remove rq_relock() sched: Improve wake_up_all_idle_cpus() take #2 irq_work: Also rcuwait for !IRQ_WORK_HARD_IRQ on PREEMPT_RT irq_work: Handle some irq_work in a per-CPU thread on PREEMPT_RT irq_work: Allow irq_work_sync() to sleep if irq_work() no IRQ support. sched/rt: Annotate the RT balancing logic irqwork as IRQ_WORK_HARD_IRQ sched: Add cluster scheduler level for x86 sched: Add cluster scheduler level in core and related Kconfig for ARM64 topology: Represent clusters of CPUs within a die sched: Disable -Wunused-but-set-variable sched: Add wrapper for get_wchan() to keep task blocked x86: Fix get_wchan() to support the ORC unwinder proc: Use task_is_running() for wchan in /proc/$pid/stat ...
2021-10-20exit: Remove calls of do_exit after noreturn versions of dieEric W. Biederman1-1/+1
On nds32, openrisc, s390, sh, and xtensa the function die never returns. Mark die __noreturn so that no one expects die to return. Remove the do_exit calls after die as they will never be reached. Cc: Jonas Bonn <jonas@southpole.se> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Stafford Horne <shorne@gmail.com> Cc: openrisc@lists.librecores.org Cc: Nick Hu <nickhu@andestech.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: linux-s390@vger.kernel.org Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: linux-sh@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Fixes: 2.3.16 Fixes: 2.3.99-pre8 Fixes: 3f65ce4d141e ("[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 5") Fixes: 664eec400bf8 ("nds32: MMU fault handling and page table management") Fixes: 61e85e367535 ("OpenRISC: Memory management") Link: https://lkml.kernel.org/r/20211020174406.17889-2-ebiederm@xmission.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-10-18xtensa: move section symbols to asm/sections.hMax Filippov1-71/+29
Introduce asm/sections.h and move section declarations to this header from setup.c. Assign section symbols char array type uniformly and drop address operator from section symbol references in code. Sort headers in setup.c while at it. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>