- 16 Sep, 2024 8 commits
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Jisheng Zhang authored
Inspired by[1], modify the code to remove the code of modifying ra to avoid imbalance RAS (return address stack) which may lead to incorret predictions on return. Link: https://lore.kernel.org/linux-riscv/20240607061335.2197383-1-cyrilbur@tenstorrent.com/ [1] Signed-off-by:
Jisheng Zhang <jszhang@kernel.org> Reviewed-by:
Cyril Bur <cyrilbur@tenstorrent.com> Link: https://lore.kernel.org/r/20240720170659.1522-1-jszhang@kernel.orgSigned-off-by:
Palmer Dabbelt <palmer@rivosinc.com>
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Palmer Dabbelt authored
Alexandre Ghiti <alexghiti@rivosinc.com> says: In RISC-V, after a new mapping is established, a sfence.vma needs to be emitted for different reasons: - if the uarch caches invalid entries, we need to invalidate it otherwise we would trap on this invalid entry, - if the uarch does not cache invalid entries, a reordered access could fail to see the new mapping and then trap (sfence.vma acts as a fence). We can actually avoid emitting those (mostly) useless and costly sfence.vma by handling the traps instead: - for new kernel mappings: only vmalloc mappings need to be taken care of, other new mapping are rare and already emit the required sfence.vma if needed. That must be achieved very early in the exception path as explained in patch 3, and this also fixes our fragile way of dealing with vmalloc faults. - for new user mappings: Svvptc makes update_mmu_cache() a no-op but we can take some gratuitous page faults (which are very unlikely though). Patch 1 and 2 introduce Svvptc extension probing. On our uarch that does not cache invalid entries and a 6.5 kernel, the gains are measurable: * Kernel boot: 6% * ltp - mmapstress01: 8% * lmbench - lat_pagefault: 20% * lmbench - lat_mmap: 5% Here are the corresponding numbers of sfence.vma emitted: * Ubuntu boot to login: Before: ~630k sfence.vma After: ~200k sfence.vma * ltp - mmapstress01 Before: ~45k After: ~6.3k * lmbench - lat_pagefault Before: ~665k After: 832 (!) * lmbench - lat_mmap Before: ~546k After: 718 (!) Thanks to Ved and Matt Evans for triggering the discussion that led to this patchset! * b4-shazam-merge: riscv: Stop emitting preventive sfence.vma for new userspace mappings with Svvptc riscv: Stop emitting preventive sfence.vma for new vmalloc mappings dt-bindings: riscv: Add Svvptc ISA extension description riscv: Add ISA extension parsing for Svvptc Link: https://lore.kernel.org/r/20240717060125.139416-1-alexghiti@rivosinc.comSigned-off-by:
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Steffen Persvold authored
commit 5944ce09 (arch_topology: Build cacheinfo from primary CPU) removed the init_cache_level() function from arch/riscv/kernel/cacheinfo.c and relies on the init_cpu_topology() function in drivers/base/arch_topology.c to call fetch_cache_info() which in turn calls init_of_cache_level() to populate the cache hierarchy information. However, init_cpu_topology() is only called from smpboot.c:smp_prepare_cpus() and thus only available when CONFIG_SMP is defined. To support non-SMP enabled kernels to still detect cache hierarchy, we add back the init_cache_level() function. The init_level_allocate_ci() function handles this gracefully on SMP-enabled kernels anyway where fetch_cache_info() is called from init_cpu_topology() earlier in the boot phase. Signed-off-by:
Steffen Persvold <spersvold@gmail.com> Link: https://lore.kernel.org/r/20240707003515.5058-1-spersvold@gmail.comSigned-off-by:
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Jinjie Ruan authored
Since commit f0bddf50 ("riscv: entry: Convert to generic entry"), _TIF_WORK_MASK is no longer used, so remove it. Fixes: f0bddf50 ("riscv: entry: Convert to generic entry") Signed-off-by:
Jinjie Ruan <ruanjinjie@huawei.com> Reviewed-by:
Guo Ren <guoren@kernel.org> Reviewed-by:
Andy Chiu <andy.chiu@sifive.com> Link: https://lore.kernel.org/r/20240711111508.1373322-1-ruanjinjie@huawei.comSigned-off-by:
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Palmer Dabbelt authored
Jisheng Zhang <jszhang@kernel.org> says: commit 76329c69 ("riscv: Use SYM_*() assembly macros instead of deprecated ones"), most riscv has been to converted the new style SYM_ assembler annotations. The remaining one is sifive's errata_cip_453.S, so convert to new style SYM_ annotations as well. After that select ARCH_USE_SYM_ANNOTATIONS. * b4-shazam-merge: riscv: select ARCH_USE_SYM_ANNOTATIONS riscv: errata: sifive: Use SYM_*() assembly macros Link: https://lore.kernel.org/r/20240709160536.3690-1-jszhang@kernel.orgSigned-off-by:
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Xiao Wang authored
The macro CONFIG_RISCV_PMU must have been defined when riscv_pmu.c gets compiled, so this patch removes the redundant check. Signed-off-by:
Xiao Wang <xiao.w.wang@intel.com> Reviewed-by:
Atish Patra <atishp@rivosinc.com> Link: https://lore.kernel.org/r/20240708121224.1148154-1-xiao.w.wang@intel.comSigned-off-by:
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Palmer Dabbelt authored
Jinjie Ruan <ruanjinjie@huawei.com> says: Add RISC-V USER_STACKTRACE support, and fix the fp alignment bug in perf_callchain_user() by the way as Björn pointed out. * b4-shazam-merge: riscv: stacktrace: Add USER_STACKTRACE support riscv: Fix fp alignment bug in perf_callchain_user() Link: https://lore.kernel.org/r/20240708032847.2998158-1-ruanjinjie@huawei.comSigned-off-by:
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Jisheng Zhang authored
This is used in poison.h for poison pointer offset. Based on current SV39, SV48 and SV57 vm layout, 0xdead000000000000 is a proper value that is not mappable, this can avoid potentially turning an oops to an expolit. Signed-off-by:
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- 15 Sep, 2024 8 commits
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Alexandre Ghiti authored
The preventive sfence.vma were emitted because new mappings must be made visible to the page table walker but Svvptc guarantees that it will happen within a bounded timeframe, so no need to sfence.vma for the uarchs that implement this extension, we will then take gratuitous (but very unlikely) page faults, similarly to x86 and arm64. This allows to drastically reduce the number of sfence.vma emitted: * Ubuntu boot to login: Before: ~630k sfence.vma After: ~200k sfence.vma * ltp - mmapstress01 Before: ~45k After: ~6.3k * lmbench - lat_pagefault Before: ~665k After: 832 (!) * lmbench - lat_mmap Before: ~546k After: 718 (!) Signed-off-by:
Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240717060125.139416-5-alexghiti@rivosinc.comSigned-off-by:
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Alexandre Ghiti authored
In 6.5, we removed the vmalloc fault path because that can't work (see [1] [2]). Then in order to make sure that new page table entries were seen by the page table walker, we had to preventively emit a sfence.vma on all harts [3] but this solution is very costly since it relies on IPI. And even there, we could end up in a loop of vmalloc faults if a vmalloc allocation is done in the IPI path (for example if it is traced, see [4]), which could result in a kernel stack overflow. Those preventive sfence.vma needed to be emitted because: - if the uarch caches invalid entries, the new mapping may not be observed by the page table walker and an invalidation may be needed. - if the uarch does not cache invalid entries, a reordered access could "miss" the new mapping and traps: in that case, we would actually only need to retry the access, no sfence.vma is required. So this patch removes those preventive sfence.vma and actually handles the possible (and unlikely) exceptions. And since the kernel stacks mappings lie in the vmalloc area, this handling must be done very early when the trap is taken, at the very beginning of handle_exception: this also rules out the vmalloc allocations in the fault path. Link: https://lore.kernel.org/linux-riscv/20230531093817.665799-1-bjorn@kernel.org/ [1] Link: https://lore.kernel.org/linux-riscv/20230801090927.2018653-1-dylan@andestech.com [2] Link: https://lore.kernel.org/linux-riscv/20230725132246.817726-1-alexghiti@rivosinc.com/ [3] Link: https://lore.kernel.org/lkml/20200508144043.13893-1-joro@8bytes.org/ [4] Signed-off-by:
Yunhui Cui <cuiyunhui@bytedance.com> Link: https://lore.kernel.org/r/20240717060125.139416-4-alexghiti@rivosinc.comSigned-off-by:
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Alexandre Ghiti authored
Add description for the Svvptc ISA extension which was ratified recently. Signed-off-by:
Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20240717060125.139416-3-alexghiti@rivosinc.comSigned-off-by:
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Alexandre Ghiti authored
Add support to parse the Svvptc string in the riscv,isa string. Signed-off-by:
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Jisheng Zhang authored
Now, riscv has been converted to the new style SYM_ assembler annotations. So select ARCH_USE_SYM_ANNOTATIONS to ensure the deprecated macros such as ENTRY(), END(), WEAK() and so on are not available and we don't regress. Signed-off-by:
Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20240709160536.3690-3-jszhang@kernel.orgSigned-off-by:
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Jisheng Zhang authored
ENTRY()/END() macros are deprecated and we should make use of the new SYM_*() macros [1] for better annotation of symbols. Replace the deprecated ones with the new ones. [1] https://docs.kernel.org/core-api/asm-annotations.htmlSigned-off-by:
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Jinjie Ruan authored
Currently, userstacktrace is unsupported for riscv. So use the perf_callchain_user() code as blueprint to implement the arch_stack_walk_user() which add userstacktrace support on riscv. Meanwhile, we can use arch_stack_walk_user() to simplify the implementation of perf_callchain_user(). A ftrace test case is shown as below: # cd /sys/kernel/debug/tracing # echo 1 > options/userstacktrace # echo 1 > options/sym-userobj # echo 1 > events/sched/sched_process_fork/enable # cat trace ...... bash-178 [000] ...1. 97.968395: sched_process_fork: comm=bash pid=178 child_comm=bash child_pid=231 bash-178 [000] ...1. 97.970075: <user stack trace> => /lib/libc.so.6[+0xb5090] Also a simple perf test is ok as below: # perf record -e cpu-clock --call-graph fp top # perf report --call-graph ..... [[31m 66.54%[[m 0.00% top [kernel.kallsyms] [k] ret_from_exception | ---ret_from_exception | |--[[31m58.97%[[m--do_trap_ecall_u | | | |--[[31m17.34%[[m--__riscv_sys_read | | ksys_read | | | | | --[[31m16.88%[[m--vfs_read | | | | | |--[[31m10.90%[[m--seq_read Signed-off-by: -
Jinjie Ruan authored
The standard RISC-V calling convention said: "The stack grows downward and the stack pointer is always kept 16-byte aligned". So perf_callchain_user() should check whether 16-byte aligned for fp. Link: https://riscv.org/wp-content/uploads/2015/01/riscv-calling.pdf Fixes: dbeb90b0 ("riscv: Add perf callchain support") Signed-off-by:
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- 14 Sep, 2024 2 commits
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Stuart Menefy authored
The original reason for reserving the top 4GiB of the direct map (space for modules/BPF/kernel) hasn't applied since the address map was reworked for KASAN. Signed-off-by:
Stuart Menefy <stuart.menefy@codasip.com> Reviewed-by:
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Changbin Du authored
The vdso.so.dbg is a debug version of vdso and could be used for debugging purpose. For example, perf-annotate requires debugging info to show source lines. So let's keep its debugging info. Signed-off-by:
Changbin Du <changbin.du@huawei.com> Reviewed-by:
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- 12 Sep, 2024 9 commits
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Palmer Dabbelt authored
Nam Cao <namcao@linutronix.de> says: Hi, For XIP kernel, the writable data section is always at offset specified in XIP_OFFSET, which is hard-coded to 32MB. Unfortunately, this means the read-only section (placed before the writable section) is restricted in size. This causes build failure if the kernel gets too large. This series remove the use of XIP_OFFSET one by one, then remove this macro entirely at the end, with the goal of lifting this size restriction. Also some cleanup and documentation along the way. * b4-shazam-merge riscv: remove limit on the size of read-only section for XIP kernel riscv: drop the use of XIP_OFFSET in create_kernel_page_table() riscv: drop the use of XIP_OFFSET in kernel_mapping_va_to_pa() riscv: drop the use of XIP_OFFSET in XIP_FIXUP_FLASH_OFFSET riscv: drop the use of XIP_OFFSET in XIP_FIXUP_OFFSET riscv: replace misleading va_kernel_pa_offset on XIP kernel riscv: don't export va_kernel_pa_offset in vmcoreinfo for XIP kernel riscv: cleanup XIP_FIXUP macro riscv: change XIP's kernel_map.size to be size of the entire kernel ... Link: https://lore.kernel.org/r/cover.1717789719.git.namcao@linutronix.deSigned-off-by:
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Nam Cao authored
XIP_OFFSET is the hard-coded offset of writable data section within the kernel. By hard-coding this value, the read-only section of the kernel (which is placed before the writable data section) is restricted in size. This causes build failures if the kernel gets too big [1]. Remove this limit. Reported-by:
kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202404211031.J6l2AfJk-lkp@intel.com [1] Signed-off-by:
Nam Cao <namcao@linutronix.de> Reviewed-by:
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Nam Cao authored
XIP_OFFSET is the hard-coded offset of writable data section within the kernel. By hard-coding this value, the read-only section of the kernel (which is placed before the writable data section) is restricted in size. As a preparation to remove this hard-coded value entirely, stop using XIP_OFFSET in create_kernel_page_table(). Instead use _sdata and _start to do the same thing. Signed-off-by:
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Nam Cao authored
XIP_OFFSET is the hard-coded offset of writable data section within the kernel. By hard-coding this value, the read-only section of the kernel (which is placed before the writable data section) is restricted in size. As a preparation to remove this hard-coded macro XIP_OFFSET entirely, remove the use of XIP_OFFSET in kernel_mapping_va_to_pa(). The macro XIP_OFFSET is used in this case to check if the virtual address is mapped to Flash or to RAM. The same check can be done with kernel_map.xiprom_sz. Signed-off-by:
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Nam Cao authored
XIP_OFFSET is the hard-coded offset of writable data section within the kernel. By hard-coding this value, the read-only section of the kernel (which is placed before the writable data section) is restricted in size. As a preparation to remove this hard-coded macro XIP_OFFSET entirely, stop using XIP_OFFSET in XIP_FIXUP_FLASH_OFFSET. Instead, use __data_loc and _sdata to do the same thing. While at it, also add a description for XIP_FIXUP_FLASH_OFFSET. Signed-off-by:
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Nam Cao authored
XIP_OFFSET is the hard-coded offset of writable data section within the kernel. By hard-coding this value, the read-only section of the kernel (which is placed before the writable data section) is restricted in size. As a preparation to remove this hard-coded macro XIP_OFFSET entirely, stop using XIP_OFFSET in XIP_FIXUP_OFFSET. Instead, use CONFIG_PHYS_RAM_BASE and _sdata to do the same thing. While at it, also add a description for XIP_FIXUP_OFFSET. Signed-off-by:
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Nam Cao authored
On XIP kernel, the name "va_kernel_pa_offset" is misleading: unlike "normal" kernel, it is not the virtual-physical address offset of kernel mapping, it is the offset of kernel mapping's first virtual address to first physical address in DRAM, which is not meaningful because the kernel's first physical address is not in DRAM. For XIP kernel, there are 2 different offsets because the read-only part of the kernel resides in ROM while the rest is in RAM. The offset to ROM is in kernel_map.va_kernel_xip_pa_offset, while the offset to RAM is not stored anywhere: it is calculated on-the-fly. Remove this confusing "va_kernel_pa_offset" and add "va_kernel_xip_data_pa_offset" as its replacement. This new variable is the offset of virtual mapping of the kernel's data portion to the corresponding physical addresses. With the introduction of this new variable, also rename va_kernel_xip_pa_offset -> va_kernel_xip_text_pa_offset to make it clear that this one is about the .text section. Signed-off-by:
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Nam Cao authored
The crash utility uses va_kernel_pa_offset to translate virtual addresses. This is incorrect in the case of XIP kernel, because va_kernel_pa_offset is not the virtual-physical address offset (yes, the name is misleading; this variable will be removed for XIP in a following commit). Stop exporting this variable for XIP kernel. The replacement is to be determined, note it as a TODO for now. Signed-off-by:
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Nam Cao authored
The XIP_FIXUP macro is used to fix addresses early during boot before MMU: generated code "thinks" the data section is in ROM while it is actually in RAM. So this macro corrects the addresses in the data section. This macro determines if the address needs to be fixed by checking if it is within the range starting from ROM address up to the size of (2 * XIP_OFFSET). This means if the kernel size is bigger than (2 * XIP_OFFSET), some addresses would not be fixed up. XIP kernel can still work if the above scenario does not happen. But this macro is obviously incorrect. Rewrite this macro to only fix up addresses within the data section. Signed-off-by:
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- 03 Sep, 2024 2 commits
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Charlie Jenkins authored
Add a missing license to vmalloc.h. Signed-off-by:
Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240729-riscv_fence_license-v1-2-7d5648069640@rivosinc.comSigned-off-by:
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Charlie Jenkins authored
Add a missing license to fence.h. Signed-off-by:
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- 15 Aug, 2024 2 commits
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Jinjie Ruan authored
Currently x86, ARM and ARM64 support generic CPU vulnerabilites, but RISC-V not, such as: # cd /sys/devices/system/cpu/vulnerabilities/ x86: # cat spec_store_bypass Mitigation: Speculative Store Bypass disabled via prctl and seccomp # cat meltdown Not affected ARM64: # cat spec_store_bypass Mitigation: Speculative Store Bypass disabled via prctl and seccomp # cat meltdown Mitigation: PTI RISC-V: # cat /sys/devices/system/cpu/vulnerabilities # ... No such file or directory As SiFive RISC-V Core IP offerings are not affected by Meltdown and Spectre, it can use the default weak function as below: # cat spec_store_bypass Not affected # cat meltdown Not affected Link: https://www.sifive.cn/blog/sifive-statement-on-meltdown-and-spectreSigned-off-by:
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Ying Sun authored
Runs on the kernel with CONFIG_RISCV_ALTERNATIVE enabled: kexec -sl vmlinux Error: kexec_image: Unknown rela relocation: 34 kexec_image: Error loading purgatory ret=-8 and kexec_image: Unknown rela relocation: 38 kexec_image: Error loading purgatory ret=-8 The purgatory code uses the 16-bit addition and subtraction relocation type, but not handled, resulting in kexec_file_load failure. So add handle to arch_kexec_apply_relocations_add(). Tested on RISC-V64 Qemu-virt, issue fixed. Co-developed-by:
Petr Tesarik <petr@tesarici.cz> Signed-off-by:
Ying Sun <sunying@isrc.iscas.ac.cn> Reviewed-by:
Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20240711083236.2859632-1-sunying@isrc.iscas.ac.cnSigned-off-by:
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- 14 Aug, 2024 2 commits
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Nam Cao authored
With XIP kernel, kernel_map.size is set to be only the size of data part of the kernel. This is inconsistent with "normal" kernel, who sets it to be the size of the entire kernel. More importantly, XIP kernel fails to boot if CONFIG_DEBUG_VIRTUAL is enabled, because there are checks on virtual addresses with the assumption that kernel_map.size is the size of the entire kernel (these checks are in arch/riscv/mm/physaddr.c). Change XIP's kernel_map.size to be the size of the entire kernel. Signed-off-by:
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Celeste Liu authored
Otherwise when the tracer changes syscall number to -1, the kernel fails to initialize a0 with -ENOSYS and subsequently fails to return the error code of the failed syscall to userspace. For example, it will break strace syscall tampering. Fixes: 52449c17 ("riscv: entry: set a0 = -ENOSYS only when syscall != -1") Reported-by:
"Dmitry V. Levin" <ldv@strace.io> Reviewed-by:
Björn Töpel <bjorn@rivosinc.com> Cc: stable@vger.kernel.org Signed-off-by:
Celeste Liu <CoelacanthusHex@gmail.com> Link: https://lore.kernel.org/r/20240627142338.5114-2-CoelacanthusHex@gmail.comSigned-off-by:
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- 07 Aug, 2024 1 commit
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Ryo Takakura authored
Add arch_trigger_cpumask_backtrace() which is a generic infrastructure for sampling other CPUs' backtrace using IPI. The feature is used when lockups are detected or in case of oops/panic if parameters are set accordingly. Below is the case of oops with the oops_all_cpu_backtrace enabled. $ sysctl kernel.oops_all_cpu_backtrace=1 triggering oops shows: [ 212.214237] NMI backtrace for cpu 1 [ 212.214390] CPU: 1 PID: 610 Comm: in:imklog Tainted: G OE 6.10.0-rc6 #1 [ 212.214570] Hardware name: riscv-virtio,qemu (DT) [ 212.214690] epc : fallback_scalar_usercopy+0x8/0xdc [ 212.214809] ra : _copy_to_user+0x20/0x40 [ 212.214913] epc : ffffffff80c3a930 ra : ffffffff8059ba7e sp : ff20000000eabb50 [ 212.215061] gp : ffffffff82066f90 tp : ff6000008e958000 t0 : 3463303866660000 [ 212.215210] t1 : 000000000000005b t2 : 3463303866666666 s0 : ff20000000eabb60 [ 212.215358] s1 : 0000000000000386 a0 : 00007ff6e81df926 a1 : ff600000824df800 [ 212.215505] a2 : 000000000000003f a3 : 7fffffffffffffc0 a4 : 0000000000000000 [ 212.215651] a5 : 000000000000003f a6 : 0000000000000000 a7 : 0000000000000000 [ 212.215857] s2 : ff600000824df800 s3 : ffffffff82066cc0 s4 : 0000000000001c1a [ 212.216074] s5 : ffffffff8206a5a8 s6 : 00007ff6e81df926 s7 : ffffffff8206a5a0 [ 212.216278] s8 : ff600000824df800 s9 : ffffffff81e25de0 s10: 000000000000003f [ 212.216471] s11: ffffffff8206a59d t3 : ff600000824df812 t4 : ff600000824df812 [ 212.216651] t5 : ff600000824df818 t6 : 0000000000040000 [ 212.216796] status: 0000000000040120 badaddr: 0000000000000000 cause: 8000000000000001 [ 212.217035] [<ffffffff80c3a930>] fallback_scalar_usercopy+0x8/0xdc [ 212.217207] [<ffffffff80095f56>] syslog_print+0x1f4/0x2b2 [ 212.217362] [<ffffffff80096e5c>] do_syslog.part.0+0x94/0x2d8 [ 212.217502] [<ffffffff800979e8>] do_syslog+0x66/0x88 [ 212.217636] [<ffffffff803a5dda>] kmsg_read+0x44/0x5c [ 212.217764] [<ffffffff80392dbe>] proc_reg_read+0x7a/0xa8 [ 212.217952] [<ffffffff802ff726>] vfs_read+0xb0/0x24e [ 212.218090] [<ffffffff803001ba>] ksys_read+0x64/0xe4 [ 212.218264] [<ffffffff8030025a>] __riscv_sys_read+0x20/0x2c [ 212.218453] [<ffffffff80c4af9a>] do_trap_ecall_u+0x60/0x1d4 [ 212.218664] [<ffffffff80c56998>] ret_from_exception+0x0/0x64 Signed-off-by:
Ryo Takakura <takakura@valinux.co.jp> Link: https://lore.kernel.org/r/20240718093659.158912-1-takakura@valinux.co.jpSigned-off-by:
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- 06 Aug, 2024 1 commit
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Alexandre Ghiti authored
commit edf2d546 ("riscv: patch: Flush the icache right after patching to avoid illegal insns") mistakenly removed the global icache flush in patch_text_nosync() and patch_text_set_nosync() functions, so reintroduce them. Fixes: edf2d546 ("riscv: patch: Flush the icache right after patching to avoid illegal insns") Reported-by:
Samuel Holland <samuel.holland@sifive.com> Closes: https://lore.kernel.org/linux-riscv/a28ddc26-d77a-470a-a33f-88144f717e86@sifive.com/Signed-off-by:
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- 05 Aug, 2024 5 commits
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Palmer Dabbelt authored
Jesse Taube <jesse@rivosinc.com> says: Add functions to pi/fdt_early.c to help parse the FDT to check if the isa string has the Zkr extension. Then use the Zkr extension to seed the KASLR base address. The first two patches fix the visibility of symbols. * b4-shazam-merge: RISC-V: Use Zkr to seed KASLR base address RISC-V: pi: Add kernel/pi/pi.h RISC-V: lib: Add pi aliases for string functions RISC-V: pi: Force hidden visibility for all symbol references Link: https://lore.kernel.org/r/20240709173937.510084-1-jesse@rivosinc.comSigned-off-by:
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Jesse Taube authored
Parse the device tree for Zkr in the isa string. If Zkr is present, use it to seed the kernel base address. On an ACPI system, as of this commit, there is no easy way to check if Zkr is present. Blindly running the instruction isn't an option as; we have to be able to trust the firmware. Signed-off-by:
Jesse Taube <jesse@rivosinc.com> Reviewed-by:
Zong Li <zong.li@sifive.com> Reviewed-by:
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Jesse Taube authored
Add pi.h header for declarations of the kernel/pi prefixed functions and any other related declarations. Suggested-by:
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Jesse Taube authored
memset, strcmp, and strncmp are all used in the __pi_ section, add SYM_FUNC_ALIAS for them. When KASAN is enabled in <asm/string.h> __pi___memset is also needed. Suggested-by:
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Jesse Taube authored
Eliminate all GOT entries in the .pi section, by forcing hidden visibility for all symbol references, which informs the compiler that such references will be resolved at link time without the need for allocating GOT entries. Include linux/hidden.h in Makefile, like arm64, for the hidden visibility attribute. Signed-off-by:
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