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2019-11-05riscv: abstract out CSR names for supervisor vs machine modeChristoph Hellwig
Many of the privileged CSRs exist in a supervisor and machine version that are used very similarly. Provide versions of the CSR names and fields that map to either the S-mode or M-mode variant depending on a new CONFIG_RISCV_M_MODE kconfig symbol. Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com> and Paul Walmsley <paul.walmsley@sifive.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> # for drivers/clocksource, drivers/irqchip [paul.walmsley@sifive.com: updated to apply] Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-28riscv: for C functions called only from assembly, mark with __visiblePaul Walmsley
Rather than adding prototypes for C functions called only by assembly code, mark them as __visible. This avoids adding prototypes that will never be used by the callers. Resolves the following sparse warnings: arch/riscv/kernel/irq.c:27:29: warning: symbol 'do_IRQ' was not declared. Should it be static? arch/riscv/kernel/ptrace.c:151:6: warning: symbol 'do_syscall_trace_enter' was not declared. Should it be static? arch/riscv/kernel/ptrace.c:165:6: warning: symbol 'do_syscall_trace_exit' was not declared. Should it be static? arch/riscv/kernel/signal.c:295:17: warning: symbol 'do_notify_resume' was not declared. Should it be static? arch/riscv/kernel/traps.c:92:1: warning: symbol 'do_trap_unknown' was not declared. Should it be static? arch/riscv/kernel/traps.c:94:1: warning: symbol 'do_trap_insn_misaligned' was not declared. Should it be static? arch/riscv/kernel/traps.c:96:1: warning: symbol 'do_trap_insn_fault' was not declared. Should it be static? arch/riscv/kernel/traps.c:98:1: warning: symbol 'do_trap_insn_illegal' was not declared. Should it be static? arch/riscv/kernel/traps.c:100:1: warning: symbol 'do_trap_load_misaligned' was not declared. Should it be static? arch/riscv/kernel/traps.c:102:1: warning: symbol 'do_trap_load_fault' was not declared. Should it be static? arch/riscv/kernel/traps.c:104:1: warning: symbol 'do_trap_store_misaligned' was not declared. Should it be static? arch/riscv/kernel/traps.c:106:1: warning: symbol 'do_trap_store_fault' was not declared. Should it be static? arch/riscv/kernel/traps.c:108:1: warning: symbol 'do_trap_ecall_u' was not declared. Should it be static? arch/riscv/kernel/traps.c:110:1: warning: symbol 'do_trap_ecall_s' was not declared. Should it be static? arch/riscv/kernel/traps.c:112:1: warning: symbol 'do_trap_ecall_m' was not declared. Should it be static? arch/riscv/kernel/traps.c:124:17: warning: symbol 'do_trap_break' was not declared. Should it be static? arch/riscv/kernel/smpboot.c:136:24: warning: symbol 'smp_callin' was not declared. Should it be static? Based on a suggestion from Luc Van Oostenryck. This version includes changes based on feedback from Christoph Hellwig <hch@lst.de>. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> # for do_syscall_trace_*
2019-10-28riscv: add missing header file includesPaul Walmsley
sparse identifies several missing prototypes caused by missing preprocessor include directives: arch/riscv/kernel/cpufeature.c:16:6: warning: symbol 'has_fpu' was not declared. Should it be static? arch/riscv/kernel/process.c:26:6: warning: symbol 'arch_cpu_idle' was not declared. Should it be static? arch/riscv/kernel/reset.c:15:6: warning: symbol 'pm_power_off' was not declared. Should it be static? arch/riscv/kernel/syscall_table.c:15:6: warning: symbol 'sys_call_table' was not declared. Should it be static? arch/riscv/kernel/traps.c:149:13: warning: symbol 'trap_init' was not declared. Should it be static? arch/riscv/kernel/vdso.c:54:5: warning: symbol 'arch_setup_additional_pages' was not declared. Should it be static? arch/riscv/kernel/smp.c:64:6: warning: symbol 'arch_match_cpu_phys_id' was not declared. Should it be static? arch/riscv/kernel/module-sections.c:89:5: warning: symbol 'module_frob_arch_sections' was not declared. Should it be static? arch/riscv/mm/context.c:42:6: warning: symbol 'switch_mm' was not declared. Should it be static? Fix by including the appropriate header files in the appropriate source files. This patch should have no functional impact. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-10-25riscv: cleanup do_trap_breakChristoph Hellwig
If we always compile the get_break_insn_length inline function we can remove the ifdefs and let dead code elimination take care of the warn branch that is now unreadable because the report_bug stub always returns BUG_TRAP_TYPE_BUG. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-14riscv: remove the switch statement in do_trap_break()Vincent Chen
To make the code more straightforward, replace the switch statement with an if statement. Suggested-by: Paul Walmsley <paul.walmsley@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> [paul.walmsley@sifive.com: cleaned up patch description; updated to apply] Link: https://lore.kernel.org/linux-riscv/20190927224711.GI4700@infradead.org/ Link: https://lore.kernel.org/linux-riscv/CABvJ_xiHJSB7P5QekuLRP=LBPzXXghAfuUpPUYb=a_HbnOQ6BA@mail.gmail.com/ Link: https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org/thread/VDCU2WOB6KQISREO4V5DTXEI2M7VOV55/ Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-07riscv: Correct the handling of unexpected ebreak in do_trap_break()Vincent Chen
For the kernel space, all ebreak instructions are determined at compile time because the kernel space debugging module is currently unsupported. Hence, it should be treated as a bug if an ebreak instruction which does not belong to BUG_TRAP_TYPE_WARN or BUG_TRAP_TYPE_BUG is executed in kernel space. For the userspace, debugging module or user problem may intentionally insert an ebreak instruction to trigger a SIGTRAP signal. To approach the above two situations, the do_trap_break() will direct the BUG_TRAP_TYPE_NONE ebreak exception issued in kernel space to die() and will send a SIGTRAP to the trapped process only when the ebreak is in userspace. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [paul.walmsley@sifive.com: fixed checkpatch issue] Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-07riscv: avoid sending a SIGTRAP to a user thread trapped in WARN()Vincent Chen
On RISC-V, when the kernel runs code on behalf of a user thread, and the kernel executes a WARN() or WARN_ON(), the user thread will be sent a bogus SIGTRAP. Fix the RISC-V kernel code to not send a SIGTRAP when a WARN()/WARN_ON() is executed. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [paul.walmsley@sifive.com: fixed subject] Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-07riscv: avoid kernel hangs when trapped in BUG()Vincent Chen
When the CONFIG_GENERIC_BUG is disabled by disabling CONFIG_BUG, if a kernel thread is trapped by BUG(), the whole system will be in the loop that infinitely handles the ebreak exception instead of entering the die function. To fix this problem, the do_trap_break() will always call the die() to deal with the break exception as the type of break is BUG_TRAP_TYPE_BUG. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-07-08Merge branch 'siginfo-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull force_sig() argument change from Eric Biederman: "A source of error over the years has been that force_sig has taken a task parameter when it is only safe to use force_sig with the current task. The force_sig function is built for delivering synchronous signals such as SIGSEGV where the userspace application caused a synchronous fault (such as a page fault) and the kernel responded with a signal. Because the name force_sig does not make this clear, and because the force_sig takes a task parameter the function force_sig has been abused for sending other kinds of signals over the years. Slowly those have been fixed when the oopses have been tracked down. This set of changes fixes the remaining abusers of force_sig and carefully rips out the task parameter from force_sig and friends making this kind of error almost impossible in the future" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus signal: Remove the signal number and task parameters from force_sig_info signal: Factor force_sig_info_to_task out of force_sig_info signal: Generate the siginfo in force_sig signal: Move the computation of force into send_signal and correct it. signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal signal: Remove the task parameter from force_sig_fault signal: Use force_sig_fault_to_task for the two calls that don't deliver to current signal: Explicitly call force_sig_fault on current signal/unicore32: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from ptrace_break signal/nds32: Remove tsk parameter from send_sigtrap signal/riscv: Remove tsk parameter from do_trap signal/sh: Remove tsk parameter from force_sig_info_fault signal/um: Remove task parameter from send_sigtrap signal/x86: Remove task parameter from send_sigtrap signal: Remove task parameter from force_sig_mceerr signal: Remove task parameter from force_sig signal: Remove task parameter from force_sigsegv ...
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 286Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 97 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.025053186@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-29signal: Remove the task parameter from force_sig_faultEric W. Biederman
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>
2019-05-29signal: Explicitly call force_sig_fault on currentEric W. Biederman
Update the calls of force_sig_fault that pass in a variable that is set to current earlier to explicitly use current. This is to make the next change that removes the task parameter from force_sig_fault easier to verify. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-29signal/riscv: Remove tsk parameter from do_trapEric W. Biederman
The do_trap function is always called with tsk == current. Make that obvious by removing the tsk parameter. This also makes it clear that do_trap calls force_sig_fault on the current task. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-16riscv: Support BUG() in kernel moduleVincent Chen
The kernel module is loaded into vmalloc region which is located below to the PAGE_OFFSET. Hence the condition, pc < PAGE_OFFSET, in the is_valid_bugaddr() will filter out all trap exceptions triggered by kernel module. To support BUG() in kernel module, the condition is changed to pc < VMALLOC_START. Signed-off-by: Vincent Chen <vincentc@andestech.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-16riscv: Add the support for c.ebreak check in is_valid_bugaddr()Vincent Chen
The macro __BUG_INSN currently is defined as the "ebreak" opcode. The is_valid_bugaddr() function compares the instruction pointed to by $sepc with macro __BUG_INSN to check whether the current trap exception is caused by an "ebreak" instruction. However, this check flow is possibly erroneous because if C extension is supported, the expected trap instruction "ebreak" is possibly translated to "c.ebreak" by the assembler. Therefore, it requires a mechanism to distinguish the length of the instruction in $spec and compare it to the correct trap instruction. Signed-off-by: Vincent Chen <vincentc@andestech.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-16RISC-V: Access CSRs using CSR numbersAnup Patel
We should prefer accessing CSRs using their CSR numbers because: 1. It compiles fine with older toolchains. 2. We can use latest CSR names in #define macro names of CSR numbers as-per RISC-V spec. 3. We can access newly added CSRs even if toolchain does not recognize newly addes CSRs by name. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-25riscv: remove duplicate macros from ptrace.hChristoph Hellwig
No need to have two names for the same thing. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: Don't increment sepc after breakpoint.Jim Wilson
Adding 4 to sepc is pointless, and is wrong if we executed a 2-byte compressed breakpoint. This plus a corresponding gdb patch allows compressed breakpoints to work in gdb. Gdb maintainers have already agreed that this is the right approach. Signed-off-by: Jim Wilson <jimw@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-06-16Merge tag 'riscv-for-linus-4.18-merge_window' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V updates from Palmer Dabbelt: "This contains some small RISC-V updates I'd like to target for 4.18. They are all fairly small this time. Here's a short summary, there's more info in the commits/merges: - a fix to __clear_user to respect the passed arguments. - enough support for the perf subsystem to work with RISC-V's ISA defined performance counters. - support for sparse and cleanups suggested by it. - support for R_RISCV_32 (a relocation, not the 32-bit ISA). - some MAINTAINERS cleanups. - the addition of CONFIG_HVC_RISCV_SBI to our defconfig, as it's always present. I've given these a simple build+boot test" * tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: RISC-V: Add CONFIG_HVC_RISCV_SBI=y to defconfig RISC-V: Handle R_RISCV_32 in modules riscv/ftrace: Export _mcount when DYNAMIC_FTRACE isn't set riscv: add riscv-specific predefines to CHECKFLAGS riscv: split the declaration of __copy_user riscv: no __user for probe_kernel_address() riscv: use NULL instead of a plain 0 perf: riscv: Add Document for Future Porting Guide perf: riscv: preliminary RISC-V support MAINTAINERS: Update Albert's email, he's back at Berkeley MAINTAINERS: Add myself as a maintainer for SiFive's drivers riscv: Fix the bug in memory access fixup code
2018-06-07riscv: no __user for probe_kernel_address()Luc Van Oostenryck
In is_valid_bugaddr(), probe_kernel_address() is called with the PC casted to (bug_inst_t __user *) but this function only take a plain void* as argument, not a __user pointer. Fix this by removing the unnneded __user in the cast. Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-25signal/riscv: Replace do_trap_siginfo with force_sig_faultEric W. Biederman
The function force_sig_fault is just the generic version of do_trap_siginfo with a (void __user *) instead of an unsigned long parameter for the address. So just use force_sig_fault to simplify the code. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <albert@sifive.com> Cc: linux-riscv@lists.infradead.org Suggested-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25signal/riscv: Use force_sig_fault where appropriateEric W. Biederman
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: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <albert@sifive.com> Cc: linux-riscv@lists.infradead.org Acked-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25signal: Ensure every siginfo we send has all bits initializedEric W. Biederman
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>
2017-09-26RISC-V: Init and Halt CodePalmer Dabbelt
This contains the various __init C functions, the initial assembly kernel entry point, and the code to reset the system. When a file was init-related this patch contains the entire file. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>