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2022-03-17RISC-V: Improve /proc/cpuinfo output for ISA extensionsAtish Patra
Currently, the /proc/cpuinfo outputs the entire riscv,isa string which is not ideal when we have multiple ISA extensions present in the ISA string. Some of them may not be enabled in kernel as well. Same goes for the single letter extensions as well which prints the entire ISA string. Some of they may not be valid ISA extensions as well (e.g 'su') Parse only the valid & enabled ISA extension and print them. Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-17RISC-V: Do no continue isa string parsing without correct XLENAtish Patra
The isa string should begin with either rv64 or rv32. Otherwise, it is an incorrect isa string. Currently, the string parsing continues even if it doesnot begin with current XLEN. Fix this by checking if it found "rv64" or "rv32" in the beginning. Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-17RISC-V: Implement multi-letter ISA extension probing frameworkAtish Patra
Multi-letter extensions can be probed using exising riscv_isa_extension_available API now. It doesn't support versioning right now as there is no use case for it. Individual extension specific implementation will be added during each extension support. Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-17RISC-V: Extract multi-letter extension names from "riscv, isa"Tsukasa OI
Currently, there is no usage for version numbers in extensions as any ratified non base ISA extension will always at v1.0. Extract the extension names in place for future parsing. Tested-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Tsukasa OI <research_trasio@irq.a4lg.com> [Improved commit text and comments] Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-17RISC-V: Minimal parser for "riscv, isa" stringsTsukasa OI
Current hart ISA ("riscv,isa") parser don't correctly parse: 1. Multi-letter extensions 2. Version numbers All ISA extensions ratified recently has multi-letter extensions (except 'H'). The current "riscv,isa" parser that is easily confused by multi-letter extensions and "p" in version numbers can be a huge problem for adding new extensions through the device tree. Leaving it would create incompatible hacks and would make "riscv,isa" value unreliable. This commit implements minimal parser for "riscv,isa" strings. With this, we can safely ignore multi-letter extensions and version numbers. [Improved commit text and fixed a bug around 's' in base extension] Signed-off-by: Atish Patra <atishp@rivosinc.com> [Fixed workaround for QEMU] Signed-off-by: Tsukasa OI <research_trasio@irq.a4lg.com> Tested-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-17RISC-V: Correctly print supported extensionsTsukasa OI
This commit replaces BITS_PER_LONG with number of alphabet letters. Current ISA pretty-printing code expects extension 'a' (bit 0) through 'z' (bit 25). Although bit 26 and higher is not currently used (thus never cause an issue in practice), it will be an annoying problem if we start to use those in the future. This commit disables printing high bits for now. Reviewed-by: Anup Patel <anup@brainfault.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Tsukasa OI <research_trasio@irq.a4lg.com> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-11RISC-V: Add SBI HSM suspend related definesAnup Patel
We add defines related to SBI HSM suspend call and also update HSM states naming as-per the latest SBI specification. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-03-10riscv: Fix auipc+jalr relocation range checksEmil Renner Berthing
RISC-V can do PC-relative jumps with a 32bit range using the following two instructions: auipc t0, imm20 ; t0 = PC + imm20 * 2^12 jalr ra, t0, imm12 ; ra = PC + 4, PC = t0 + imm12 Crucially both the 20bit immediate imm20 and the 12bit immediate imm12 are treated as two's-complement signed values. For this reason the immediates are usually calculated like this: imm20 = (offset + 0x800) >> 12 imm12 = offset & 0xfff ..where offset is the signed offset from the auipc instruction. When the 11th bit of offset is 0 the addition of 0x800 doesn't change the top 20 bits and imm12 considered positive. When the 11th bit is 1 the carry of the addition by 0x800 means imm20 is one higher, but since imm12 is then considered negative the two's complement representation means it all cancels out nicely. However, this addition by 0x800 (2^11) means an offset greater than or equal to 2^31 - 2^11 would overflow so imm20 is considered negative and result in a backwards jump. Similarly the lower range of offset is also moved down by 2^11 and hence the true 32bit range is [-2^31 - 2^11, 2^31 - 2^11) Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> Fixes: e2c0cdfba7f6 ("RISC-V: User-facing API") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-10resume_user_mode: Move to resume_user_mode.hEric W. Biederman
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h. While doing that rename tracehook_notify_resume to resume_user_mode_work. Update all of the places that included tracehook.h for these functions to include resume_user_mode.h instead. Update all of the callers of tracehook_notify_resume to call resume_user_mode_work. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-10ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.hEric W. Biederman
Rename tracehook_report_syscall_{entry,exit} to ptrace_report_syscall_{entry,exit} and place them in ptrace.h There is no longer any generic tracehook infractructure so make these ptrace specific functions ptrace specific. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-3-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-10RISC-V: Add SBI HSM suspend related definesAnup Patel
We add defines related to SBI HSM suspend call and also update HSM states naming as-per latest SBI specification. Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-10RISC-V: Add arch functions for non-retentive suspend entry/exitAnup Patel
The hart registers and CSRs are not preserved in non-retentative suspend state so we provide arch specific helper functions which will save/restore hart context upon entry/exit to non-retentive suspend state. These helper functions can be used by cpuidle drivers for non-retentive suspend entry/exit. Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Guo Ren <guoren@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-10RISC-V: Rename relocate() and make it globalAnup Patel
The low-level relocate() function enables mmu and relocates execution to link-time addresses. We rename relocate() function to relocate_enable_mmu() function which is more informative. Also, the relocate_enable_mmu() function will be used in the resume path when a CPU wakes-up from a non-retentive suspend so we make it global symbol. Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-03-10RISC-V: Enable CPU_IDLE driversAnup Patel
We force select CPU_PM and provide asm/cpuidle.h so that we can use CPU IDLE drivers for Linux RISC-V kernel. Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Anup Patel <apatel@vetanamicro.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-25uaccess: fix type mismatch warnings from access_ok()Arnd Bergmann
On some architectures, access_ok() does not do any argument type checking, so replacing the definition with a generic one causes a few warnings for harmless issues that were never caught before. Fix the ones that I found either through my own test builds or that were reported by the 0-day bot. Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-24riscv: fix oops caused by irqsoff latency tracerChangbin Du
The trace_hardirqs_{on,off}() require the caller to setup frame pointer properly. This because these two functions use macro 'CALLER_ADDR1' (aka. __builtin_return_address(1)) to acquire caller info. If the $fp is used for other purpose, the code generated this macro (as below) could trigger memory access fault. 0xffffffff8011510e <+80>: ld a1,-16(s0) 0xffffffff80115112 <+84>: ld s2,-8(a1) # <-- paging fault here The oops message during booting if compiled with 'irqoff' tracer enabled: [ 0.039615][ T0] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000f8 [ 0.041925][ T0] Oops [#1] [ 0.042063][ T0] Modules linked in: [ 0.042864][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.17.0-rc1-00233-g9a20c48d1ed2 #29 [ 0.043568][ T0] Hardware name: riscv-virtio,qemu (DT) [ 0.044343][ T0] epc : trace_hardirqs_on+0x56/0xe2 [ 0.044601][ T0] ra : restore_all+0x12/0x6e [ 0.044721][ T0] epc : ffffffff80126a5c ra : ffffffff80003b94 sp : ffffffff81403db0 [ 0.044801][ T0] gp : ffffffff8163acd8 tp : ffffffff81414880 t0 : 0000000000000020 [ 0.044882][ T0] t1 : 0098968000000000 t2 : 0000000000000000 s0 : ffffffff81403de0 [ 0.044967][ T0] s1 : 0000000000000000 a0 : 0000000000000001 a1 : 0000000000000100 [ 0.045046][ T0] a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000 [ 0.045124][ T0] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000054494d45 [ 0.045210][ T0] s2 : ffffffff80003b94 s3 : ffffffff81a8f1b0 s4 : ffffffff80e27b50 [ 0.045289][ T0] s5 : ffffffff81414880 s6 : ffffffff8160fa00 s7 : 00000000800120e8 [ 0.045389][ T0] s8 : 0000000080013100 s9 : 000000000000007f s10: 0000000000000000 [ 0.045474][ T0] s11: 0000000000000000 t3 : 7fffffffffffffff t4 : 0000000000000000 [ 0.045548][ T0] t5 : 0000000000000000 t6 : ffffffff814aa368 [ 0.045620][ T0] status: 0000000200000100 badaddr: 00000000000000f8 cause: 000000000000000d [ 0.046402][ T0] [<ffffffff80003b94>] restore_all+0x12/0x6e This because the $fp(aka. $s0) register is not used as frame pointer in the assembly entry code. resume_kernel: REG_L s0, TASK_TI_PREEMPT_COUNT(tp) bnez s0, restore_all REG_L s0, TASK_TI_FLAGS(tp) andi s0, s0, _TIF_NEED_RESCHED beqz s0, restore_all call preempt_schedule_irq j restore_all To fix above issue, here we add one extra level wrapper for function trace_hardirqs_{on,off}() so they can be safely called by low level entry code. Signed-off-by: Changbin Du <changbin.du@gmail.com> Fixes: 3c4697982982 ("riscv: Enable LOCKDEP_SUPPORT & fixup TRACE_IRQFLAGS_SUPPORT") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-14riscv: mm: Set sv57 on defaultlyQinglin Pan
This patch sets sv57 on defaultly if CONFIG_64BIT. And do fallback to try to set sv48 on boot time if sv57 is not supported in current hardware. Signed-off-by: Qinglin Pan <panqinglin2020@iscas.ac.cn> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-14RISC-V: Fix IPI/RFENCE hmask on non-monotonic hartid orderingGeert Uytterhoeven
If the boot CPU does not have the lowest hartid, "hartid - hbase" can become negative, leading to an incorrect hmask, causing userspace to crash with SEGV. This is observed on e.g. Starlight Beta, where cpuid 1 maps to hartid 0, and cpuid 0 maps to hartid 1. Fix this by detecting this case, and shifting the accumulated mask and updating hbase, if possible. Fixes: 26fb751ca37846c9 ("RISC-V: Do not use cpumask data structure for hartid bitmap") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Tested-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-14RISC-V: Fix handling of empty cpu masksGeert Uytterhoeven
The cpumask rework slightly changed the behavior of the code. Fix this by treating an empty cpumask as meaning all online CPUs. Extracted from a patch by Atish Patra <atishp@rivosinc.com>. Reported-by: Jessica Clarke <jrtc27@jrtc27.com> Fixes: 26fb751ca37846c9 ("RISC-V: Do not use cpumask data structure for hartid bitmap") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-14RISC-V: Fix hartid mask handling for hartid 31 and upGeert Uytterhoeven
Jessica reports that using "1 << hartid" causes undefined behavior for hartid 31 and up. Fix this by using the BIT() helper instead of an explicit shift. Reported-by: Jessica Clarke <jrtc27@jrtc27.com> Fixes: 26fb751ca37846c9 ("RISC-V: Do not use cpumask data structure for hartid bitmap") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-10riscv: cpu-hotplug: clear cpu from numa map when teardownPingfan Liu
There is numa_add_cpu() when cpus online, accordingly, there should be numa_remove_cpu() when cpus offline. Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Fixes: 4f0e8eef772e ("riscv: Add numa support for riscv64 platform") Cc: stable@vger.kernel.org [Palmer: Add missing NUMA include] Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-04riscv: Fix XIP_FIXUP_FLASH_OFFSETMyrtle Shah
There were several problems with the calculation. Not only was an 'and' being computed into t1 but thrown away; but the 'and' itself would cause problems if the granularity of the XIP physical address was less than XIP_OFFSET - in my case I had the kernel image at 2MB in SPI flash. Fixes: f9ace4ede49b ("riscv: remove .text section size limitation for XIP") Cc: stable@vger.kernel.org Signed-off-by: Myrtle Shah <gatecat@ds0.me> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-02-04riscv: eliminate unreliable __builtin_frame_address(1)Changbin Du
I tried different pieces of code which uses __builtin_frame_address(1) (with both gcc version 7.5.0 and 10.3.0) to verify whether it works as expected on riscv64. The result is negative. What the compiler had generated is as below: 31 fp = (unsigned long)__builtin_frame_address(1); 0xffffffff80006024 <+200>: ld s1,0(s0) It takes '0(s0)' as the address of frame 1 (caller), but the actual address should be '-16(s0)'. | ... | <-+ +-----------------+ | | return address | | | previous fp | | | saved registers | | | local variables | | $fp --> | ... | | +-----------------+ | | return address | | | previous fp --------+ | saved registers | $sp --> | local variables | +-----------------+ This leads the kernel can not dump the full stack trace on riscv. [ 7.222126][ T1] Call Trace: [ 7.222804][ T1] [<ffffffff80006058>] dump_backtrace+0x2c/0x3a This problem is not exposed on most riscv builds just because the '0(s0)' occasionally is the address frame 2 (caller's caller), if only ra and fp are stored in frame 1 (caller). | ... | <-+ +-----------------+ | | return address | | $fp --> | previous fp | | +-----------------+ | | return address | | | previous fp --------+ | saved registers | $sp --> | local variables | +-----------------+ This could be a *bug* of gcc that should be fixed. But as noted in gcc manual "Calling this function with a nonzero argument can have unpredictable effects, including crashing the calling program.", let's remove the '__builtin_frame_address(1)' in backtrace code. With this fix now it can show full stack trace: [ 10.444838][ T1] Call Trace: [ 10.446199][ T1] [<ffffffff8000606c>] dump_backtrace+0x2c/0x3a [ 10.447711][ T1] [<ffffffff800060ac>] show_stack+0x32/0x3e [ 10.448710][ T1] [<ffffffff80a005c0>] dump_stack_lvl+0x58/0x7a [ 10.449941][ T1] [<ffffffff80a005f6>] dump_stack+0x14/0x1c [ 10.450929][ T1] [<ffffffff804c04ee>] ubsan_epilogue+0x10/0x5a [ 10.451869][ T1] [<ffffffff804c092e>] __ubsan_handle_load_invalid_value+0x6c/0x78 [ 10.453049][ T1] [<ffffffff8018f834>] __pagevec_release+0x62/0x64 [ 10.455476][ T1] [<ffffffff80190830>] truncate_inode_pages_range+0x132/0x5be [ 10.456798][ T1] [<ffffffff80190ce0>] truncate_inode_pages+0x24/0x30 [ 10.457853][ T1] [<ffffffff8045bb04>] kill_bdev+0x32/0x3c ... Signed-off-by: Changbin Du <changbin.du@gmail.com> Fixes: eac2f3059e02 ("riscv: stacktrace: fix the riscv stacktrace when CONFIG_FRAME_POINTER enabled") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Remove redundant err variableMinghao Chi
Return value from user_regset_copyin() directly instead of taking this in another redundant variable. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn> Signed-off-by: CGEL ZTE <cgel.zte@gmail.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Do not use cpumask data structure for hartid bitmapAtish Patra
Currently, SBI APIs accept a hartmask that is generated from struct cpumask. Cpumask data structure can hold upto NR_CPUs value. Thus, it is not the correct data structure for hartids as it can be higher than NR_CPUs for platforms with sparse or discontguous hartids. Remove all association between hartid mask and struct cpumask. Reviewed-by: Anup Patel <anup@brainfault.org> (For Linux RISC-V changes) Acked-by: Anup Patel <anup@brainfault.org> (For KVM RISC-V changes) Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Move spinwait booting method to its own configAtish Patra
The spinwait booting method should only be used for platforms with older firmware without SBI HSM extension or M-mode firmware because spinwait method can't support cpu hotplug, kexec or sparse hartid. It is better to move the entire spinwait implementation to its own config which can be disabled if required. It is enabled by default to maintain backward compatibility and M-mode Linux. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Move the entire hart selection via lottery to SMPAtish Patra
The booting hart selection via lottery is only useful for SMP systems. Moreover, the lottery selection is only necessary for systems using spinwait booting method. It is better to keep the entire lottery selection together so that it can be disabled in future. Move the lottery selection code to under CONFIG_SMP. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Use __cpu_up_stack/task_pointer only for spinwait methodAtish Patra
The __cpu_up_stack/task_pointer array is only used for spinwait method now. The per cpu array based lookup is also fragile for platforms with discontiguous/sparse hartids. The spinwait method is only used for M-mode Linux or older firmwares without SBI HSM extension. For general Linux systems, ordered booting method is preferred anyways to support cpu hotplug and kexec. Make sure that __cpu_up_stack/task_pointer is only used for spinwait method. Take this opportunity to rename it to __cpu_spinwait_stack/task_pointer to emphasize the purpose as well. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Do not print the SBI version during HSM extension boot printAtish Patra
The HSM extension information log also prints the SBI version v0.2. This is misleading as the underlying firmware SBI version may be different from v0.2. Remove the unncessary printing of SBI version. Signed-off-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Avoid using per cpu array for ordered bootingAtish Patra
Currently both order booting and spinwait approach uses a per cpu array to update stack & task pointer. This approach will not work for the following cases. 1. If NR_CPUs are configured to be less than highest hart id. 2. A platform has sparse hartid. This issue can be fixed for ordered booting as the booting cpu brings up one cpu at a time using SBI HSM extension which has opaque parameter that is unused until now. Introduce a common secondary boot data structure that can store the stack and task pointer. Secondary harts will use this data while booting up to setup the sp & tp. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-19RISC-V: Introduce sv48 support without relocatable kernelPalmer Dabbelt
This patchset allows to have a single kernel for sv39 and sv48 without being relocatable. The idea comes from Arnd Bergmann who suggested to do the same as x86, that is mapping the kernel to the end of the address space, which allows the kernel to be linked at the same address for both sv39 and sv48 and then does not require to be relocated at runtime. This implements sv48 support at runtime. The kernel will try to boot with 4-level page table and will fallback to 3-level if the HW does not support it. Folding the 4th level into a 3-level page table has almost no cost at runtime. Note that kasan region had to be moved to the end of the address space since its location must be known at compile-time and then be valid for both sv39 and sv48 (and sv57 that is coming). * riscv-sv48-v3: riscv: Explicit comment about user virtual address space size riscv: Use pgtable_l4_enabled to output mmu_type in cpuinfo riscv: Implement sv48 support asm-generic: Prepare for riscv use of pud_alloc_one and pud_free riscv: Allow to dynamically define VA_BITS riscv: Introduce functions to switch pt_ops riscv: Split early kasan mapping to prepare sv48 introduction riscv: Move KASAN mapping next to the kernel mapping riscv: Get rid of MAXPHYSMEM configs Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-19riscv: Use pgtable_l4_enabled to output mmu_type in cpuinfoAlexandre Ghiti
Now that the mmu type is determined at runtime using SATP characteristic, use the global variable pgtable_l4_enabled to output mmu type of the processor through /proc/cpuinfo instead of relying on device tree infos. Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-19riscv: Implement sv48 supportAlexandre Ghiti
By adding a new 4th level of page table, give the possibility to 64bit kernel to address 2^48 bytes of virtual address: in practice, that offers 128TB of virtual address space to userspace and allows up to 64TB of physical memory. If the underlying hardware does not support sv48, we will automatically fallback to a standard 3-level page table by folding the new PUD level into PGDIR level. In order to detect HW capabilities at runtime, we use SATP feature that ignores writes with an unsupported mode. Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-19Merge tag 'riscv-for-linus-5.17-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the DA9063 as used on the HiFive Unmatched. - Support for relative extables, which puts us in line with other architectures and save some space in vmlinux. - A handful of kexec fixes/improvements, including the ability to run crash kernels from PCI-addressable memory on the HiFive Unmatched. - Support for the SBI SRST extension, which allows systems that do not have an explicit driver in Linux to reboot. - A handful of fixes and cleanups, including to the defconfigs and device trees. * tag 'riscv-for-linus-5.17-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (52 commits) RISC-V: Use SBI SRST extension when available riscv: mm: fix wrong phys_ram_base value for RV64 RISC-V: Use common riscv_cpuid_to_hartid_mask() for both SMP=y and SMP=n riscv: head: remove useless __PAGE_ALIGNED_BSS and .balign riscv: errata: alternative: mark vendor_patch_func __initdata riscv: head: make secondary_start_common() static riscv: remove cpu_stop() riscv: try to allocate crashkern region from 32bit addressible memory riscv: use hart id instead of cpu id on machine_kexec riscv: Don't use va_pa_offset on kdump riscv: dts: sifive: fu540-c000: Fix PLIC node riscv: dts: sifive: fu540-c000: Drop bogus soc node compatible values riscv: dts: sifive: Group tuples in register properties riscv: dts: sifive: Group tuples in interrupt properties riscv: dts: microchip: mpfs: Group tuples in interrupt properties riscv: dts: microchip: mpfs: Fix clock controller node riscv: dts: microchip: mpfs: Fix reference clock node riscv: dts: microchip: mpfs: Fix PLIC node riscv: dts: microchip: mpfs: Drop empty chosen node riscv: dts: canaan: Group tuples in interrupt properties ...
2022-01-17Merge branch 'signal-for-v5.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc/<pid>/stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...
2022-01-12Merge tag 'perf_core_for_v5.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Borislav Petkov: "Cleanup of the perf/kvm interaction." * tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Drop guest callback (un)register stubs KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c KVM: arm64: Hide kvm_arm_pmu_available behind CONFIG_HW_PERF_EVENTS=y KVM: arm64: Convert to the generic perf callbacks KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c KVM: Move x86's perf guest info callbacks to generic KVM KVM: x86: More precisely identify NMI from guest when handling PMI KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu variable perf/core: Use static_call to optimize perf_guest_info_callbacks perf: Force architectures to opt-in to guest callbacks perf: Add wrappers for invoking guest callbacks perf/core: Rework guest callbacks to prepare for static_call support perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscv perf: Stop pretending that perf can handle multiple guest callbacks KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest KVM: x86: Register perf callbacks after calling vendor's hardware_setup() perf: Protect perf_guest_cbs with RCU
2022-01-11RISC-V: Use SBI SRST extension when availableAnup Patel
The SBI SRST extension provides a standard way to poweroff and reboot the system irrespective to whether Linux RISC-V S-mode is running natively (HS-mode) or inside Guest/VM (VS-mode). The SBI SRST extension is available in the SBI v0.3 specification. (Refer, https://github.com/riscv/riscv-sbi-doc/releases/tag/v0.3.0-rc1) This patch extends Linux RISC-V SBI implementation to detect and use SBI SRST extension. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-09RISC-V: Use common riscv_cpuid_to_hartid_mask() for both SMP=y and SMP=nSean Christopherson
Use what is currently the SMP=y version of riscv_cpuid_to_hartid_mask() for both SMP=y and SMP=n to fix a build failure with KVM=m and SMP=n due to boot_cpu_hartid not being exported. This also fixes a second bug where the SMP=n version assumes the sole CPU in the system is in the incoming mask, which may not hold true in kvm_riscv_vcpu_sbi_ecall() if the KVM guest VM has multiple vCPUs (on a SMP=n system). Fixes: 1ef46c231df4 ("RISC-V: Implement new SBI v0.2 extensions") Reported-by: Adam Borowski <kilobyte@angband.pl> Reviewed-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-09riscv: head: remove useless __PAGE_ALIGNED_BSS and .balignJisheng Zhang
After commit 83e7b8769a08 ("RISC-V: move empty_zero_page definition to C and export it"), the empty_zero_page has been moved outside head.S, the __PAGE_ALIGNED_BSS and .balign LoCs are useless, clean up them. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-09riscv: head: make secondary_start_common() staticJisheng Zhang
There are no users outside head.S so make secondary_start_common() static. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-09riscv: remove cpu_stop()Jisheng Zhang
Except arch_cpu_idle_dead(), no users of this function. So remove cpu_stop() and fold its code into arch_cpu_idle_dead(). Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-09riscv: use hart id instead of cpu id on machine_kexecNick Kossifidis
raw_smp_processor_id() doesn't return the hart id as stated in arch/riscv/include/asm/smp.h, use smp_processor_id() instead to get the cpu id, and cpuid_to_hartid_map() to pass the hart id to the next kernel. This fixes kexec on HiFive Unleashed/Unmatched where cpu ids and hart ids don't match (on qemu-virt they match). Fixes: fba8a8674f68 ("RISC-V: Add kexec support") Signed-off-by: Nick Kossifidis <mick@ics.forth.gr> Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-09riscv: Don't use va_pa_offset on kdumpNick Kossifidis
On kdump instead of using an intermediate step to relocate the kernel, that lives in a "control buffer" outside the current kernel's mapping, we jump to the crash kernel directly by calling riscv_kexec_norelocate(). The current implementation uses va_pa_offset while switching to physical addressing, however since we moved the kernel outside the linear mapping this won't work anymore since riscv_kexec_norelocate() is part of the kernel mapping and we should use kernel_map.va_kernel_pa_offset, and also take XIP kernel into account. We don't really need to use va_pa_offset on riscv_kexec_norelocate, we can just set STVEC to the physical address of the new kernel instead and let the hart jump to the new kernel on the next instruction after setting SATP to zero. This fixes kdump and is also simpler/cleaner. I tested this on the latest qemu and HiFive Unmatched and works as expected. Fixes: 2bfc6cd81bd1 ("riscv: Move kernel mapping outside of linear mapping") Signed-off-by: Nick Kossifidis <mick@ics.forth.gr> Reviewed-by: Alexandre Ghiti <alex@ghiti.fr> Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-07riscv/head: fix misspelling of guaranteedhasheddan
Fixes misspelling of guaranteed in comment describing why fetching fence is guaranteed to work when switching to kernel page tables. Signed-off-by: hasheddan <georgedanielmangum@gmail.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-05riscv: vmlinux.lds.S|vmlinux-xip.lds.S: remove `.fixup` sectionJisheng Zhang
These are no longer necessary now that we have a more standard extable mechanism. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-05riscv: extable: add `type` and `data` fieldsJisheng Zhang
This is a riscv port of commit d6e2cc564775 ("arm64: extable: add `type` and `data` fields"). Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2021-12-13exit: Add and use make_task_dead.Eric W. Biederman
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>
2021-12-10arch: Make ARCH_STACKWALK independent of STACKTRACEPeter Zijlstra
Make arch_stack_walk() available for ARCH_STACKWALK architectures without it being entangled in STACKTRACE. Link: https://lore.kernel.org/lkml/20211022152104.356586621@infradead.org/ Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> [Mark: rebase, drop unnecessary arm change] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/20211129142849.3056714-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-11-17perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscvSean Christopherson
Drop "support" for guest callbacks from architectures that don't implement the guest callbacks. Future patches will convert the callbacks to static_call; rather than churn a bunch of arch code (that was presumably copy+pasted from x86), remove it wholesale as it's useless and at best wasting cycles. A future patch will also add a Kconfig to force architcture to opt into the callbacks to make it more difficult for uses "support" to sneak in in the future. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20211111020738.2512932-6-seanjc@google.com
2021-11-17perf: Protect perf_guest_cbs with RCUSean Christopherson
Protect perf_guest_cbs with RCU to fix multiple possible errors. Luckily, all paths that read perf_guest_cbs already require RCU protection, e.g. to protect the callback chains, so only the direct perf_guest_cbs touchpoints need to be modified. Bug #1 is a simple lack of WRITE_ONCE/READ_ONCE behavior to ensure perf_guest_cbs isn't reloaded between a !NULL check and a dereference. Fixed via the READ_ONCE() in rcu_dereference(). Bug #2 is that on weakly-ordered architectures, updates to the callbacks themselves are not guaranteed to be visible before the pointer is made visible to readers. Fixed by the smp_store_release() in rcu_assign_pointer() when the new pointer is non-NULL. Bug #3 is that, because the callbacks are global, it's possible for readers to run in parallel with an unregisters, and thus a module implementing the callbacks can be unloaded while readers are in flight, resulting in a use-after-free. Fixed by a synchronize_rcu() call when unregistering callbacks. Bug #1 escaped notice because it's extremely unlikely a compiler will reload perf_guest_cbs in this sequence. perf_guest_cbs does get reloaded for future derefs, e.g. for ->is_user_mode(), but the ->is_in_guest() guard all but guarantees the consumer will win the race, e.g. to nullify perf_guest_cbs, KVM has to completely exit the guest and teardown down all VMs before KVM start its module unload / unregister sequence. This also makes it all but impossible to encounter bug #3. Bug #2 has not been a problem because all architectures that register callbacks are strongly ordered and/or have a static set of callbacks. But with help, unloading kvm_intel can trigger bug #1 e.g. wrapping perf_guest_cbs with READ_ONCE in perf_misc_flags() while spamming kvm_intel module load/unload leads to: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 6 PID: 1825 Comm: stress Not tainted 5.14.0-rc2+ #459 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:perf_misc_flags+0x1c/0x70 Call Trace: perf_prepare_sample+0x53/0x6b0 perf_event_output_forward+0x67/0x160 __perf_event_overflow+0x52/0xf0 handle_pmi_common+0x207/0x300 intel_pmu_handle_irq+0xcf/0x410 perf_event_nmi_handler+0x28/0x50 nmi_handle+0xc7/0x260 default_do_nmi+0x6b/0x170 exc_nmi+0x103/0x130 asm_exc_nmi+0x76/0xbf Fixes: 39447b386c84 ("perf: Enhance perf to allow for guest statistic collection from host") Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20211111020738.2512932-2-seanjc@google.com