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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 Filippov1-0/+12
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: support coprocessors on SMPMax Filippov1-1/+12
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: 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: 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 Filippov1-3/+4
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: move trace_hardirqs_off call back to entry.SMax Filippov1-9/+2
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: 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>
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>
2021-11-10Merge 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 ...
2021-10-20exit: 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: remove unused variable wmaskMax Filippov1-3/+1
After a cleanup the function show_regs doesn't use variable wmask but still computes it. Drop it. Fixes: 8d7e8240e66c ("[XTENSA] Clean up elf-gregset.") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2021-10-18xtensa: only build windowed register support code when neededMax Filippov1-0/+2
There's no need in window overflow/underflow/alloca exception handlers or window spill code when neither kernel nor userspace support windowed registers. Don't build or link it. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2021-08-11xtensa: add fairness to IRQ handlingMax Filippov1-0/+7
Track which IRQs have been served at each level to make sure that no IRQ is served more than once while other IRQs at the same level are pending. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2020-06-09mm: reorder includes after introduction of linux/pgtable.hMike Rapoport1-1/+1
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include of the latter in the middle of asm includes. Fix this up with the aid of the below script and manual adjustments here and there. import sys import re if len(sys.argv) is not 3: print "USAGE: %s <file> <header>" % (sys.argv[0]) sys.exit(1) hdr_to_move="#include <linux/%s>" % sys.argv[2] moved = False in_hdrs = False with open(sys.argv[1], "r") as f: lines = f.readlines() for _line in lines: line = _line.rstrip(' ') if line == hdr_to_move: continue if line.startswith("#include <linux/"): in_hdrs = True elif not moved and in_hdrs: moved = True print hdr_to_move print line Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mm: introduce include/linux/pgtable.hMike Rapoport1-1/+1
The include/linux/pgtable.h is going to be the home of generic page table manipulation functions. Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and make the latter include asm/pgtable.h. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09kernel: rename show_stack_loglvl() => show_stack()Dmitry Safonov1-8/+2
Now the last users of show_stack() got converted to use an explicit log level, show_stack_loglvl() can drop it's redundant suffix and become once again well known show_stack(). Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09xtensa: add show_stack_loglvl()Dmitry Safonov1-4/+10
Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Link: http://lkml.kernel.org/r/20200418201944.482088-44-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09xtensa: add loglvl to show_trace()Dmitry Safonov1-5/+9
Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Add log level argument to show_trace() as a preparation for introducing show_stack_loglvl(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u [rppt@kernel.org: build fix] Link: http://lkml.kernel.org/r/20200511194534.GA1018386@kernel.org Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Rapoport <rppt@kernel.org> Link: http://lkml.kernel.org/r/20200418201944.482088-43-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-08sched/rt, xtensa: Use CONFIG_PREEMPTIONThomas Gleixner1-2/+5
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Switch the entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT output to die(). [bigeasy: +traps.c] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Cc: Chris Zankel <chris@zankel.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-xtensa@linux-xtensa.org Link: https://lore.kernel.org/r/20191015191821.11479-21-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-26xtensa: make stack dump size configurableMax Filippov1-1/+1
Introduce Kconfig symbol PRINT_STACK_DEPTH and use it to initialize kstack_depth_to_print. Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-11-26xtensa: improve stack dumpingMax Filippov1-16/+11
Calculate printable stack size and use print_hex_dump instead of opencoding it. Drop extra newline output in show_trace as its output format does not depend on CONFIG_KALLSYMS. Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-09-01xtensa: add support for call0 ABI in userspaceMax Filippov1-0/+4
Provide a Kconfig choice to select whether only the default ABI, only call0 ABI or both are supported. The default for XEA2 is windowed, but it may change for XEA3. Call0 only runs userspace with PS.WOE disabled. Supporting both windowed and call0 ABIs is tricky, as there's no indication in the ELF binaries which ABI they use. So it is done by probing: each process is started with PS.WOE disabled, but the handler of an illegal instruction exception taken with PS.WOE retries faulting instruction after enabling PS.WOE. It must happen before any signal is delivered to the process, otherwise it may be delivered incorrectly. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-29signal: Remove the task parameter from force_sig_faultEric W. Biederman1-1/+1
As synchronous exceptions really only make sense against the current task (otherwise how are you synchronous) remove the task parameter from from force_sig_fault to make it explicit that is what is going on. The two known exceptions that deliver a synchronous exception to a stopped ptraced task have already been changed to force_sig_fault_to_task. The callers have been changed with the following emacs regular expression (with obvious variations on the architectures that take more arguments) to avoid typos: force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)] -> force_sig_fault(\1,\2,\3) Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-27signal: Remove task parameter from force_sigEric W. Biederman1-3/+3
All of the remaining callers pass current into force_sig so remove the task parameter to make this obvious and to make misuse more difficult in the future. This also makes it clear force_sig passes current into force_sig_info. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-02-07xtensa: simplify trap_initMax Filippov1-3/+2
Drop redundant 'fast &&' condition from the exception handler assignment loop. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-12-04xtensa: clean up WSR*/RSR*/get_sr/set_srMax Filippov1-4/+4
WSR and RSR are too generic and collide with other macro definitions in the kernel causing warnings in allmodconfig builds. Drop WSR and RSR macros and WSR_* and RSR_* variants. Change get_sr and set_sr to xtensa_get_sr and xtensa_set_sr. Fix up users. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-12-03xtensa: drop fast_syscall_kernelMax Filippov1-2/+0
There must be no xtensa-specific syscalls from the kernel code: register spilling uses call+entry sequence and atomics have proper function implementations. Drop fast_syscall_xtensa. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-04-25signal/xtensa: Use force_sig_fault where appropriateEric W. Biederman1-9/+1
Filling in struct siginfo before calling force_sig_info a tedious and error prone process, where once in a great while the wrong fields are filled out, and siginfo has been inconsistently cleared. Simplify this process by using the helper force_sig_fault. Which takes as a parameters all of the information it needs, ensures all of the fiddly bits of filling in struct siginfo are done properly and then calls force_sig_info. In short about a 5 line reduction in code for every time force_sig_info is called, which makes the calling function clearer. Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Chris Zankel <chris@zankel.net> Cc: linux-xtensa@linux-xtensa.org Acked-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25signal/xtensa: Consistenly use SIGBUS in do_unaligned_userEric W. Biederman1-1/+1
While working on changing this code to use force_sig_fault I discovered that do_unaliged_user is sets si_signo to SIGBUS and passes SIGSEGV to force_sig_info. Which is just b0rked. The code is reporting a SIGBUS error so replace the SIGSEGV with SIGBUS. Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: linux-xtensa@linux-xtensa.org Cc: stable@vger.kernel.org Acked-by: Max Filippov <jcmvbkbc@gmail.com> Fixes: 5a0015d62668 ("[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 3") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25signal: Ensure every siginfo we send has all bits initializedEric W. Biederman1-0/+1
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-12-16xtensa: clean up exception handling structureMax Filippov1-20/+19
Instead of using flat array of longs use normal C structure and generate EXC_TABLE_* constants in the asm-offsets.c Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-12-16xtensa: clean up custom-controlled debug outputMax Filippov1-11/+14
Replace #ifdef'fed/commented out debug printk statements with pr_debug. Replace printk statements with pr_* equivalents. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-03-31xtensa: fix stack dump outputMax Filippov1-4/+2
Use %pB in pr_cont format string instead of calling print_symbol separately. It turns [ 19.166249] Call Trace: [ 19.167265] [<a000e50a>] [ 19.167843] __warn+0x92/0xa0 [ 19.169656] [<a000e554>] [ 19.170059] warn_slowpath_fmt+0x3c/0x40 [ 19.171934] [<a02d5bd8>] back into [ 18.123240] Call Trace: [ 18.125039] [<a000e4f6>] __warn+0x92/0xa0 [ 18.126961] [<a000e540>] warn_slowpath_fmt+0x3c/0x40 Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-03-02sched/headers: Prepare to move kstack_end() from <linux/sched.h> to <linux/sched/task_stack.h>Ingo Molnar1-0/+1
But first update the usage sites with the new header dependency. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>Ingo Molnar1-1/+1
We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds1-1/+1
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-06xtensa: clean up printk usage for boot/crash loggingMax Filippov1-52/+22
Convert printk(KERN_* to pr_* and printk's without level to pr_cont. This fixes torn register dumps, stack dumps, stack traces and timestamps in the middle of 'Calibrating CPU frequency' message. Also drop unused show_code and drop false comment about show_stack. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-03-11xtensa: support hardware breakpoints/watchpointsMax Filippov1-0/+14
Use perf framework to manage hardware instruction and data breakpoints. Add two new ptrace calls: PTRACE_GETHBPREGS and PTRACE_SETHBPREGS to query and set instruction and data breakpoints. Address bit 0 choose instruction (0) or data (1) break register, bits 31..1 are the register number. Both calls transfer two 32-bit words: address (0) and control (1). Instruction breakpoint contorl word is 0 to clear breakpoint, 1 to set. Data breakpoint control word bit 31 is 'trigger on store', bit 30 is 'trigger on load, bits 29..0 are length. Length 0 is used to clear a breakpoint. To set a breakpoint length must be a power of 2 in the range 1..64 and the address must be length-aligned. Introduce new thread_info flag: TIF_DB_DISABLED. Set it if debug exception is raised by the kernel code accessing watched userspace address and disable corresponding data breakpoint. On exit to userspace check that flag and, if set, restore all data breakpoints. Handle debug exceptions raised with PS.EXCM set. This may happen when window overflow/underflow handler or fast exception handler hits data breakpoint, in which case save and disable all data breakpoints, single-step faulting instruction and restore data breakpoints. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-03-11xtensa: use context structure for debug exceptionsMax Filippov1-0/+13
With implementation of data breakpoints debug exceptions raised when PS.EXCM is set need to be handled, e.g. window overflow code can write to watched userspace address. Currently debug exception handler uses EXCSAVE and DEPC SRs to save temporary registers, but DEPC may not be available when PS.EXCM is set and more space will be needed to save additional state. Reorganize debug context: create per-CPU structure debug_table instance and store its address in the EXCSAVE<debug level> instead of debug_exception function address. Expand this structure when more save space is needed. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-03-11xtensa: remove remaining non-functional KGDB bitsMax Filippov1-19/+0
KGDB is not supported on xtensa, but there are bits of related code under arch/xtensa/kernel. Remove these bits. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-01-11xtensa: make fake NMI configurableMax Filippov1-0/+27
Do not always use fake NMI when safe, provide Kconfig option instead. Print a warning if fake NMI is chosen in unsafe configuration, but allow it, because it may work if the user knows that interrupts with priorities at or above PMM IRQ are not used. Add a check to NMI handler that BUGs if any of these IRQs fire. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2015-08-17xtensa: implement fake NMIMax Filippov1-0/+26
In case perf IRQ is the highest of the medium-level IRQs, and is alone on its level, it may be treated as NMI: - LOCKLEVEL is defined to be one level less than EXCM level, - IRQ masking never lowers current IRQ level, - new fake exception cause code, EXCCAUSE_MAPPED_NMI is assigned to that IRQ; new second level exception handler, do_nmi, assigned to it handles it as NMI, - atomic operations in configurations without s32c1i still need to mask all interrupts. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2015-08-17xtensa: reorganize irq flags tracingMax Filippov1-1/+4
entry.s only disables IRQs on hardware IRQ, move trace_hardirqs_off call into do_interrupt. Check actual intlevel that will be restored on return from exception handler to decide if trace_hardirqs_on should be called. Annotate IRQ on/off points in the TIF_* handling loop on return from exception handler. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2014-08-14xtensa: don't allow overflow/underflow on unaligned stackMax Filippov1-4/+1
Double exceptions that happen during register window overflow/underflow are handled in the topmost stack frame, as if it was the only exception that occured. However unaligned access exception handler is special because it needs to analyze instruction that caused the exception, but the userspace instruction that triggered window exception is completely irrelevant. Unaligned data access is rather normal in the generic userspace code, but stack pointer manipulation must always be done by architecture-aware code and thus unaligned stack means a serious problem anyway. Use the default unaligned access handler that raises SIGBUS in case of unaligned access in window overflow/underflow handler. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2014-01-14xtensa: implement CPU hotplugMax Filippov1-2/+2
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Chris Zankel <chris@zankel.net>