summaryrefslogtreecommitdiff
path: root/arch/riscv/kernel
AgeCommit message (Collapse)Author
2020-06-09riscv: add show_stack_loglvl()Dmitry Safonov
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: Albert Ou <aou@eecs.berkeley.edu> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Link: http://lkml.kernel.org/r/20200418201944.482088-28-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09kallsyms/printk: add loglvl to print_ip_sym()Dmitry Safonov
Patch series "Add log level to show_stack()", v3. Add log level argument to show_stack(). Done in three stages: 1. Introducing show_stack_loglvl() for every architecture 2. Migrating old users with an explicit log level 3. Renaming show_stack_loglvl() into show_stack() Justification: - It's a design mistake to move a business-logic decision into platform realization detail. - I have currently two patches sets that would benefit from this work: Removing console_loglevel jumps in sysrq driver [1] Hung task warning before panic [2] - suggested by Tetsuo (but he probably didn't realise what it would involve). - While doing (1), (2) the backtraces were adjusted to headers and other messages for each situation - so there won't be a situation when the backtrace is printed, but the headers are missing because they have lesser log level (or the reverse). - As the result in (2) plays with console_loglevel for kdb are removed. The least important for upstream, but maybe still worth to note that every company I've worked in so far had an off-list patch to print backtrace with the needed log level (but only for the architecture they cared about). If you have other ideas how you will benefit from show_stack() with a log level - please, reply to this cover letter. See also discussion on v1: https://lore.kernel.org/linux-riscv/20191106083538.z5nlpuf64cigxigh@pathway.suse.cz/ This patch (of 50): print_ip_sym() needs to have a log level parameter to comply with other parts being printed. Otherwise, half of the expected backtrace would be printed and other may be missing with some logging level. The following callee(s) are using now the adjusted log level: - microblaze/unwind: the same level as headers & userspace unwind. Note that pr_debug()'s there are for debugging the unwinder itself. - nds32/traps: symbol addresses are printed with the same log level as backtrace headers. - lockdep: ip for locking issues is printed with the same log level as other part of the warning. - sched: ip where preemption was disabled is printed as error like the rest part of the message. - ftrace: bug reports are now consistent in the log level being used. Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Ben Segall <bsegall@google.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Burton <paulburton@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Will Deacon <will@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Dmitry Safonov <dima@arista.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com> Cc: Mark Salter <msalter@redhat.com> Cc: Guo Ren <guoren@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Brian Cain <bcain@codeaurora.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Helge Deller <deller@gmx.de> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Rich Felker <dalias@libc.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Jason Wessel <jason.wessel@windriver.com> Link: http://lkml.kernel.org/r/20200418201944.482088-2-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04Merge tag 'riscv-for-linus-5.8-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - The remainder of the code necessary to support the Kendryte K210: * Support for building device trees into the kernel, as the K210 doesn't have a bootloader that provides one * A K210 device tree and the associated defconfig update * Support for skipping PMP initialization on systems that trap on PMP accesses rather than treating them as WARL - Support for KGDB - Improvements to text patching - Some cleanups to the SiFive L2 cache driver * tag 'riscv-for-linus-5.8-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: soc: sifive: l2 cache: Mark l2_get_priv_group as static soc: sifive: l2 cache: Eliminate an unsigned zero compare warning riscv: Add support to determine no. of L2 cache way enabled riscv: cacheinfo: Implement cache_get_priv_group with a generic ops structure riscv: Use text_mutex instead of patch_lock riscv: Use NOKPROBE_SYMBOL() instead of __krpobes annotation riscv: Remove the 'riscv_' prefix of function name riscv: Add SW single-step support for KDB riscv: Use the XML target descriptions to report 3 system registers riscv: Add KGDB support kgdb: Add kgdb_has_hit_break function RISC-V: Skip setting up PMPs on traps riscv: K210: Update defconfig riscv: K210: Add a built-in device tree riscv: Allow device trees to be built into the kernel
2020-05-21RISC-V: gp_in_global needs register keywordPalmer Dabbelt
The Intel kernel build robot recently pointed out that I missed the register keyword on this one when I refactored the code to remove local register variables (which aren't supported by LLVM). GCC's manual indicates that global register variables must have the register keyword, As far as I can tell lacking the register keyword causes GCC to ignore the __asm__ and treat this as a regular variable, but I'm not sure how that didn't show up as some sort of failure. Fixes: 52e7c52d2ded ("RISC-V: Stop relying on GCC's register allocator's hueristics") Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-20riscv: cacheinfo: Implement cache_get_priv_group with a generic ops structureYash Shah
Implement cache_get_priv_group() that will make use of a generic ops structure to return a private attribute group for custom cache info. Using riscv_set_cacheinfo_ops() users can hook their own custom function to return the private attribute group for cacheinfo. In future we can add more ops to this generic ops structure for SOC specific cacheinfo. Signed-off-by: Yash Shah <yash.shah@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18riscv: Use text_mutex instead of patch_lockZong Li
We don't need the additional lock protection when patching the text. There are two patching interfaces here: - patch_text: patch code and always synchronize with stop_machine() - patch_text_nosync: patch code without synchronization, it's caller's responsibility to synchronize all CPUs if needed. For the first one, stop_machine() is protected by its own mutex, and also the irq is already disabled here. For the second one, in risc-v real case now, it would be used to ftrace patching the mcount function, since it already running under kstop_machine(), no other thread will run, so we could use text_mutex on ftrace side. Signed-off-by: Zong Li <zong.li@sifive.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18riscv: Use NOKPROBE_SYMBOL() instead of __krpobes annotationZong Li
The __kprobes annotation is old style, so change it to NOKPROBE_SYMBOL(). Signed-off-by: Zong Li <zong.li@sifive.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18riscv: Remove the 'riscv_' prefix of function nameZong Li
Refactor the function name by removing the 'riscv_' prefix, it would be better unless it could mix up with arch-independent functions. Signed-off-by: Zong Li <zong.li@sifive.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18riscv: Add SW single-step support for KDBVincent Chen
In KGDB, the GDB in the host is responsible for the single-step operation of the software. In other words, KGDB does not need to derive the next pc address when performing a software single-step operation. KGDB just inserts the break instruction at the indicated address according to the GDB instructions. This approach does not work in KDB because the GDB does not involve the KDB process. Therefore, this patch provides KDB a software single-step mechanism to use. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18riscv: Use the XML target descriptions to report 3 system registersVincent Chen
The $status, $badaddr, and $cause registers belong to the thread context, so KGDB can obtain their contents from pt_regs in each trap. However, the sequential number of these registers in the gdb register list is far from the general-purpose registers. If riscv port uses the existing method to report these three registers, many trivial registers with sequence numbers in the middle of them will also be packaged to the reply packets. To solve this problem, the riscv port wants to introduce the GDB target description mechanism to customize the reported register list. By the list, the KGDB can ignore the intermediate registers and just reports the general-purpose registers and these three system registers. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18riscv: Add KGDB supportVincent Chen
The skeleton of RISC-V KGDB port. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18RISC-V: Skip setting up PMPs on trapsPalmer Dabbelt
The RISC-V ISA manual says that PMPs are WARL, but it appears the K210 doesn't implement them and instead traps on the unsupported accesses. This patch handles those traps by just skipping the PMP initialization entirely, under the theory that machines that trap on PMP accesses must allow memory accesses as otherwise they're pretty useless. Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-18riscv: Allow device trees to be built into the kernelPalmer Dabbelt
Some systems don't provide a useful device tree to the kernel on boot. Chasing around bootloaders for these systems is a headache, so instead le't's just keep a device tree table in the kernel, keyed by the SOC's unique identifier, that contains the relevant DTB. This is only implemented for M mode right now. While we could implement this via the SBI calls that allow access to these identifiers, we don't have any systems that need this right now. Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-12riscv: stacktrace: Fix undefined reference to `walk_stackframe'Kefeng Wang
Drop static declaration to fix following build error if FRAME_POINTER disabled, riscv64-linux-ld: arch/riscv/kernel/perf_callchain.o: in function `.L0': perf_callchain.c:(.text+0x2b8): undefined reference to `walk_stackframe' Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-12riscv: perf: RISCV_BASE_PMU should be independentKefeng Wang
Selecting PERF_EVENTS without selecting RISCV_BASE_PMU results in a build error. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> [Palmer: commit text] Fixes: 178e9fc47aae("perf: riscv: preliminary RISC-V support") Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-11riscv: perf_event: Make some funciton staticKefeng Wang
Fixes the following warning detected when running make with W=1, ../arch/riscv/kernel/perf_event.c:150:5: warning: no previous prototype for ‘riscv_map_cache_decode’ [-Wmissing-prototypes] int riscv_map_cache_decode(u64 config, unsigned int *type, ^~~~~~~~~~~~~~~~~~~~~~ ../arch/riscv/kernel/perf_event.c:345:13: warning: no previous prototype for ‘riscv_base_pmu_handle_irq’ [-Wmissing-prototypes] irqreturn_t riscv_base_pmu_handle_irq(int irq_num, void *dev) ^~~~~~~~~~~~~~~~~~~~~~~~~ ../arch/riscv/kernel/perf_event.c:364:6: warning: no previous prototype for ‘release_pmc_hardware’ [-Wmissing-prototypes] void release_pmc_hardware(void) ^~~~~~~~~~~~~~~~~~~~ ../arch/riscv/kernel/perf_event.c:467:12: warning: no previous prototype for ‘init_hw_perf_events’ [-Wmissing-prototypes] int __init init_hw_perf_events(void) ^~~~~~~~~~~~~~~~~~~ Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-04riscv: force __cpu_up_ variables to put in data sectionZong Li
Put __cpu_up_stack_pointer and __cpu_up_task_pointer in data section. Currently, these two variables are put in bss section, there is a potential risk that secondary harts get the uninitialized value before main hart finishing the bss clearing. In this case, all secondary harts would pass the waiting loop and enable the MMU before main hart set up the page table. This issue happens on random booting of multiple harts, which means it will manifest for BBL and OpenSBI v0.6 (or older version). In OpenSBI v0.7 (or higher version), we have HSM extension so all the secondary harts are brought-up by Linux kernel in an orderly fashion. This means we don't need this change for OpenSBI v0.7 (or higher version). Signed-off-by: Zong Li <zong.li@sifive.com> Reviewed-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-04riscv: add Linux note to vdsoAndreas Schwab
The Linux note in the vdso allows glibc to check the running kernel version without having to issue the uname syscall. Signed-off-by: Andreas Schwab <schwab@suse.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-04RISC-V: Add bitmap reprensenting ISA features common across CPUsAnup Patel
This patch adds riscv_isa bitmap which represents Host ISA features common across all Host CPUs. The riscv_isa is not same as elf_hwcap because elf_hwcap will only have ISA features relevant for user-space apps whereas riscv_isa will have ISA features relevant to both kernel and user-space apps. One of the use-case for riscv_isa bitmap is in KVM hypervisor where we will use it to do following operations: 1. Check whether hypervisor extension is available 2. Find ISA features that need to be virtualized (e.g. floating point support, vector extension, etc.) Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Alexander Graf <graf@amazon.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-04RISC-V: Export riscv_cpuid_to_hartid_mask() APIAnup Patel
The riscv_cpuid_to_hartid_mask() API should be exported to allow building KVM RISC-V as loadable module. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-21riscv: sbi: Fix undefined reference to sbi_shutdownKefeng Wang
There is no shutdown call in SBI v0.2, only set pm_power_off when RISCV_SBI_V01 enabled to fix following build error, riscv64-linux-ld: arch/riscv/kernel/sbi.o: in function `sbi_power_off': sbi.c:(.text+0xe): undefined reference to `sbi_shutdown Fixes: efca13989250 ("RISC-V: Introduce a new config for SBI v0.1") Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-21riscv: sbi: Correct sbi_shutdown() and sbi_clear_ipi() exportKefeng Wang
Fix incorrect EXPORT_SYMBOL(). Fixes: efca13989250 ("RISC-V: Introduce a new config for SBI v0.1") Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-21riscv: fix vdso build with lldIlie Halip
When building with the LLVM linker this error occurrs: LD arch/riscv/kernel/vdso/vdso-syms.o ld.lld: error: no input files This happens because the lld treats -R as an alias to -rpath, as opposed to ld where -R means --just-symbols. Use the long option name for compatibility between the two. Link: https://github.com/ClangBuiltLinux/linux/issues/805 Reported-by: Dmitry Golovin <dima@golovin.in> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Ilie Halip <ilie.halip@gmail.com> Reviewed-by: Fangrui Song <maskray@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-21RISC-V: stacktrace: Declare sp_in_global outside ifdefGuenter Roeck
riscv:allnoconfig and riscv:tinyconfig fail to compile. arch/riscv/kernel/stacktrace.c: In function 'walk_stackframe': arch/riscv/kernel/stacktrace.c:78:8: error: 'sp_in_global' undeclared sp_in_global is declared inside CONFIG_FRAME_POINTER but used outside of it. Fixes: 52e7c52d2ded ("RISC-V: Stop relying on GCC's register allocator's hueristics") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-09Merge tag 'riscv-for-linus-5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "This contains a handful of new features: - Partial support for the Kendryte K210. There are still a few outstanding issues that I have patches for, but I don't actually have a board to test them so they're not included yet. - SBI v0.2 support. - Fixes to support for building with LLVM-based toolchains. The resulting images are known not to boot yet. I don't anticipate a part two, but I'll probably have something early in the RCs to finish up the K210 support" * tag 'riscv-for-linus-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (38 commits) riscv: create a loader.bin boot image for Kendryte SoC riscv: Kendryte K210 default config riscv: Add Kendryte K210 device tree riscv: Select required drivers for Kendryte SOC riscv: Add Kendryte K210 SoC support riscv: Add SOC early init support riscv: Unaligned load/store handling for M_MODE RISC-V: Support cpu hotplug RISC-V: Add supported for ordered booting method using HSM RISC-V: Add SBI HSM extension definitions RISC-V: Export SBI error to linux error mapping function RISC-V: Add cpu_ops and modify default booting method RISC-V: Move relocate and few other functions out of __init RISC-V: Implement new SBI v0.2 extensions RISC-V: Introduce a new config for SBI v0.1 RISC-V: Add SBI v0.2 extension definitions RISC-V: Add basic support for SBI v0.2 RISC-V: Mark existing SBI as 0.1 SBI. riscv: Use macro definition instead of magic number riscv: Add support to dump the kernel page tables ...
2020-04-03Merge tag 'spdx-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments
2020-04-03riscv: Add SOC early init supportDamien Le Moal
Add a mechanism for early SoC initialization for platforms that need additional hardware initialization not possible through the regular device tree and drivers mechanism. With this, a SoC specific initialization function can be called very early, before DTB parsing is done by parse_dtb() in Linux RISC-V kernel setup code. This can be very useful for early hardware initialization for No-MMU kernels booted directly in M-mode because it is quite likely that no other booting stage exist prior to the No-MMU kernel. Example use of a SoC early initialization is as follows: static void vendor_abc_early_init(const void *fdt) { /* * some early init code here that can use simple matches * against the flat device tree file. */ } SOC_EARLY_INIT_DECLARE("vendor,abc", abc_early_init); This early initialization function is executed only if the flat device tree for the board has a 'compatible = "vendor,abc"' entry; Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-03riscv: Unaligned load/store handling for M_MODEDamien Le Moal
Add handlers for unaligned load and store traps that may be generated by applications. Code heavily inspired from the OpenSBI project. Handling of the unaligned access traps is suitable for applications compiled with or without compressed instructions and is independent of the kernel CONFIG_RISCV_ISA_C option value. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Support cpu hotplugAtish Patra
This patch enable support for cpu hotplug in RISC-V. It uses SBI HSM extension to online/offline any hart. As a result, the harts are returned to firmware once they are offline. If the harts are brought online afterwards, they re-enter Linux kernel as if a secondary hart booted for the first time. All booting requirements are honored during this process. Tested both on QEMU and HighFive Unleashed board with. Test result follows. --------------------------------------------------- Offline cpu 2 --------------------------------------------------- $ echo 0 > /sys/devices/system/cpu/cpu2/online [ 32.828684] CPU2: off $ cat /proc/cpuinfo processor : 0 hart : 0 isa : rv64imafdcsu mmu : sv48 processor : 1 hart : 1 isa : rv64imafdcsu mmu : sv48 processor : 3 hart : 3 isa : rv64imafdcsu mmu : sv48 processor : 4 hart : 4 isa : rv64imafdcsu mmu : sv48 processor : 5 hart : 5 isa : rv64imafdcsu mmu : sv48 processor : 6 hart : 6 isa : rv64imafdcsu mmu : sv48 processor : 7 hart : 7 isa : rv64imafdcsu mmu : sv48 --------------------------------------------------- online cpu 2 --------------------------------------------------- $ echo 1 > /sys/devices/system/cpu/cpu2/online $ cat /proc/cpuinfo processor : 0 hart : 0 isa : rv64imafdcsu mmu : sv48 processor : 1 hart : 1 isa : rv64imafdcsu mmu : sv48 processor : 2 hart : 2 isa : rv64imafdcsu mmu : sv48 processor : 3 hart : 3 isa : rv64imafdcsu mmu : sv48 processor : 4 hart : 4 isa : rv64imafdcsu mmu : sv48 processor : 5 hart : 5 isa : rv64imafdcsu mmu : sv48 processor : 6 hart : 6 isa : rv64imafdcsu mmu : sv48 processor : 7 hart : 7 isa : rv64imafdcsu mmu : sv48 Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org>
2020-03-31RISC-V: Add supported for ordered booting method using HSMAtish Patra
Currently, all harts have to jump Linux in RISC-V. This complicates the multi-stage boot process as every transient stage also has to ensure all harts enter to that stage and jump to Linux afterwards. It also obstructs a clean Kexec implementation. SBI HSM extension provides alternate solutions where only a single hart need to boot and enter Linux. The booting hart can bring up secondary harts one by one afterwards. Add SBI HSM based cpu_ops that implements an ordered booting method in RISC-V. This change is also backward compatible with older firmware not implementing HSM extension. If a latest kernel is used with older firmware, it will continue to use the default spinning booting method. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Export SBI error to linux error mapping functionAtish Patra
All SBI related extensions will not be implemented in sbi.c to avoid bloating. Thus, sbi_err_map_linux_errno() will be used in other files implementing that specific extension. Export the function so that it can be used later. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Add cpu_ops and modify default booting methodAtish Patra
Currently, all non-booting harts start booting after the booting hart updates the per-hart stack pointer. This is done in a way that, it's difficult to implement any other booting method without breaking the backward compatibility. Define a cpu_ops method that allows to introduce other booting methods in future. Modify the current booting method to be compatible with cpu_ops. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Move relocate and few other functions out of __initAtish Patra
The secondary hart booting and relocation code are under .init section. As a result, it will be freed once kernel booting is done. However, ordered booting protocol and CPU hotplug always requires these functions to be present to bringup harts after initial kernel boot. Move the required functions to a different section and make sure that they are in memory within first 2MB offset as trampoline page directory only maps first 2MB. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Implement new SBI v0.2 extensionsAtish Patra
Few v0.1 SBI calls are being replaced by new SBI calls that follows v0.2 calling convention. Implement the replacement extensions and few additional new SBI function calls that makes way for a better SBI interface in future. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Introduce a new config for SBI v0.1Atish Patra
We now have SBI v0.2 which is more scalable and extendable to handle future needs for RISC-V supervisor interfaces. Introduce a new config and move all SBI v0.1 code under that config. This allows to implement the new replacement SBI extensions cleanly and remove v0.1 extensions easily in future. Currently, the config is enabled by default. Once all M-mode software, with v0.1, is no longer in use, this config option and all relevant code can be easily removed. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Add basic support for SBI v0.2Atish Patra
The SBI v0.2 introduces a base extension which is backward compatible with v0.1. Implement all helper functions and minimum required SBI calls from v0.2 for now. All other base extension function will be added later as per need. As v0.2 calling convention is backward compatible with v0.1, remove the v0.1 helper functions and just use v0.2 calling convention. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-30Merge tag 'irq-core-2020-03-30' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Updates for the interrupt subsystem: Treewide: - Cleanup of setup_irq() which is not longer required because the memory allocator is available early. Most cleanup changes come through the various maintainer trees, so the final removal of setup_irq() is postponed towards the end of the merge window. Core: - Protection against unsafe invocation of interrupt handlers and unsafe interrupt injection including a fixup of the offending PCI/AER error injection mechanism. Invoking interrupt handlers from arbitrary contexts, i.e. outside of an actual interrupt, can cause inconsistent state on the fragile x86 interrupt affinity changing hardware trainwreck. Drivers: - Second wave of support for the new ARM GICv4.1 - Multi-instance support for Xilinx and PLIC interrupt controllers - CPU-Hotplug support for PLIC - The obligatory new driver for X1000 TCU - Enhancements, cleanups and fixes all over the place" * tag 'irq-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) unicore32: Replace setup_irq() by request_irq() sh: Replace setup_irq() by request_irq() hexagon: Replace setup_irq() by request_irq() c6x: Replace setup_irq() by request_irq() alpha: Replace setup_irq() by request_irq() irqchip/gic-v4.1: Eagerly vmap vPEs irqchip/gic-v4.1: Add VSGI property setup irqchip/gic-v4.1: Add VSGI allocation/teardown irqchip/gic-v4.1: Move doorbell management to the GICv4 abstraction layer irqchip/gic-v4.1: Plumb set_vcpu_affinity SGI callbacks irqchip/gic-v4.1: Plumb get/set_irqchip_state SGI callbacks irqchip/gic-v4.1: Plumb mask/unmask SGI callbacks irqchip/gic-v4.1: Add initial SGI configuration irqchip/gic-v4.1: Plumb skeletal VSGI irqchip irqchip/stm32: Retrigger both in eoi and unmask callbacks irqchip/gic-v3: Move irq_domain_update_bus_token to after checking for NULL domain irqchip/xilinx: Do not call irq_set_default_host() irqchip/xilinx: Enable generic irq multi handler irqchip/xilinx: Fill error code when irq domain registration fails irqchip/xilinx: Add support for multiple instances ...
2020-03-26riscv: patch code by fixmap mappingZong Li
On strict kernel memory permission, the ftrace have to change the permission of text for dynamic patching the intructions. Use riscv_patch_text_nosync() to patch code instead of probe_kernel_write. Signed-off-by: Zong Li <zong.li@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26riscv: introduce interfaces to patch kernel codeZong Li
On strict kernel memory permission, we couldn't patch code without writable permission. Preserve two holes in fixmap area, so we can map the kernel code temporarily to fixmap area, then patch the instructions. We need two pages here because we support the compressed instruction, so the instruction might be align to 2 bytes. When patching the 32-bit length instruction which is 2 bytes alignment, it will across two pages. Introduce two interfaces to patch kernel code: riscv_patch_text_nosync: - patch code without synchronization, it's caller's responsibility to synchronize all CPUs if needed. riscv_patch_text: - patch code and always synchronize with stop_machine() Signed-off-by: Zong Li <zong.li@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26riscv: add macro to get instruction lengthZong Li
Extract the calculation of instruction length for common use. Signed-off-by: Zong Li <zong.li@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26riscv: add alignment for text, rodata and data sectionsZong Li
The kernel mapping will tried to optimize its mapping by using bigger size. In rv64, it tries to use PMD_SIZE, and tryies to use PGDIR_SIZE in rv32. To ensure that the start address of these sections could fit the mapping entry size, make them align to the biggest alignment. Define a macro SECTION_ALIGN because the HPAGE_SIZE or PMD_SIZE, etc., are invisible in linker script. This patch is prepared for STRICT_KERNEL_RWX support. Signed-off-by: Zong Li <zong.li@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26riscv: move exception table immediately after RO_DATAZong Li
Move EXCEPTION_TABLE immediately after RO_DATA. Make it easy to set the attribution of the sections which should be read-only at a time. Add _data to specify the start of data section with write permission. This patch is prepared for STRICT_KERNEL_RWX support. Signed-off-by: Zong Li <zong.li@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-25.gitignore: add SPDX License IdentifierMasahiro Yamada
Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18riscv: fix the IPI missing issue in nommu modeGreentime Hu
This patch fixes the IPI(inner processor interrupt) missing issue. It failed because it used hartid_mask to iterate for_each_cpu(), however the cpu_mask and hartid_mask may not be always the same. It will never send the IPI to hartid 4 because it will be skipped in for_each_cpu loop in my case. We can reproduce this case in Qemu sifive_u machine by this command. qemu-system-riscv64 -nographic -smp 5 -m 1G -M sifive_u -kernel \ arch/riscv/boot/loader It will hang in csd_lock_wait(csd) because the csd_unlock(csd) is not called. It is not called because hartid 4 doesn't receive the IPI to release this lock. The caller hart doesn't send the IPI to hartid 4 is because of hartid 4 is skipped in for_each_cpu(). It will be skipped is because "(cpu) < nr_cpu_ids" is not true. The hartid is 4 and nr_cpu_ids is 4. Therefore it should use cpumask in for_each_cpu() instead of hartid_mask. /* Send a message to all CPUs in the map */ arch_send_call_function_ipi_mask(cfd->cpumask_ipi); if (wait) { for_each_cpu(cpu, cfd->cpumask) { call_single_data_t *csd; csd = per_cpu_ptr(cfd->csd, cpu); csd_lock_wait(csd); } } for ((cpu) = -1; \ (cpu) = cpumask_next((cpu), (mask)), \ (cpu) < nr_cpu_ids;) It could boot to login console after this patch applied. Fixes: b2d36b5668f6 ("riscv: provide native clint access for M-mode") Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-16irqchip/sifive-plic: Enable/Disable external interrupts upon cpu online/offlineAtish Patra
Currently, PLIC threshold is only initialized once in the beginning. However, threshold can be set to disabled if a CPU is marked offline with CPU hotplug feature. This will not allow to change the irq affinity to a CPU that just came online. Add PLIC specific CPU hotplug callbacks and enable the threshold when a CPU comes online. Take this opportunity to move the external interrupt enable code from trap init to PLIC driver as well. On cpu offline path, the driver performs the exact opposite operations i.e. disable the interrupt and the threshold. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20200302231146.15530-2-atish.patra@wdc.com
2020-03-05riscv: fix seccomp reject syscall code pathTycho Andersen
If secure_computing() rejected a system call, we were previously setting the system call number to -1, to indicate to later code that the syscall failed. However, if something (e.g. a user notification) was sleeping, and received a signal, we may set a0 to -ERESTARTSYS and re-try the system call again. In this case, seccomp "denies" the syscall (because of the signal), and we would set a7 to -1, thus losing the value of the system call we want to restart. Instead, let's return -1 from do_syscall_trace_enter() to indicate that the syscall was rejected, so we don't clobber the value in case of -ERESTARTSYS or whatever. This commit fixes the user_notification_signal seccomp selftest on riscv to no longer hang. That test expects the system call to be re-issued after the signal, and it wasn't due to the above bug. Now that it is, everything works normally. Note that in the ptrace (tracer) case, the tracer can set the register values to whatever they want, so we still need to keep the code that handles out-of-bounds syscalls. However, we can drop the comment. We can also drop syscall_set_nr(), since it is no longer used anywhere, and the code that re-loads the value in a7 because of it. Reported in: https://lore.kernel.org/bpf/CAEn-LTp=ss0Dfv6J00=rCAy+N78U2AmhqJNjfqjr2FDpPYjxEQ@mail.gmail.com/ Reported-by: David Abdurachmanov <david.abdurachmanov@gmail.com> Signed-off-by: Tycho Andersen <tycho@tycho.ws> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03RISC-V: Inline the assembly register save/restore macrosPalmer Dabbelt
These are only used once, and when reading the code I've always found them to be more of a headache than a benefit. While they were never worth removing before, LLVM's integrated assembler doesn't support LOCAL so rather that trying to figure out how to refactor the macros it seems saner to just inline them. Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03RISC-V: Stop relying on GCC's register allocator's hueristicsPalmer Dabbelt
GCC allows users to hint to the register allocation that a variable should be placed in a register by using a syntax along the lines of function(...) { register long in_REG __asm__("REG"); } We've abused this a bit throughout the RISC-V port to access fixed registers directly as C variables. In practice it's never going to blow up because GCC isn't going to allocate these registers, but it's not a well defined syntax so we really shouldn't be relying upon this. Luckily there is a very similar but well defined syntax that allows us to still access these registers directly as C variables, which is to simply declare the register variables globally. For fixed variables this doesn't change the ABI. LLVM disallows this ambiguous syntax, so this isn't just strictly a formatting change. Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03RISC-V: Stop putting .sbss in .sdataPalmer Dabbelt
I don't know why we were doing this, as it's been there since the beginning. After d841f729e655 ("riscv: force hart_lottery to put in .sdata section") my guess would be that it made the kernel boot and we forgot to fix it more cleanly. The default .bss segment already contains the .sbss section, so we don't need to do anything additional to ensure the symbols in .sbss continue to work. Tested-by: Zong Li <zong.li@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03riscv: force hart_lottery to put in .sdata sectionZong Li
In PIC code model, the zero initialized data always be put in .bss section, so when building kernel as PIE, the hart_lottery won't present in small data section, and it causes more than one harts to get the lottery, because the main hart clears the content of .bss section immediately after it getting the lottery. Signed-off-by: Zong Li <zong.li@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> [Palmer: added a comment] Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>