summaryrefslogtreecommitdiff
path: root/arch/loongarch/kernel
AgeCommit message (Collapse)AuthorFilesLines
2023-09-06LoongArch: Get partial stack information when providing regs parameterEnze Li1-8/+10
Currently, arch_stack_walk() can only get the full stack information including NMI. This is because the implementation of arch_stack_walk() is forced to ignore the information passed by the regs parameter and use the current stack information instead. For some detection systems like KFENCE, only partial stack information is needed. In particular, the stack frame where the interrupt occurred. To support KFENCE, this patch modifies the implementation of the arch_stack_walk() function so that if this function is called with the regs argument passed, it retains all the stack information in regs and uses it to provide accurate information. Before this patch: [ 1.531195 ] ================================================================== [ 1.531442 ] BUG: KFENCE: out-of-bounds read in stack_trace_save_regs+0x48/0x6c [ 1.531442 ] [ 1.531900 ] Out-of-bounds read at 0xffff800012267fff (1B left of kfence-#12): [ 1.532046 ] stack_trace_save_regs+0x48/0x6c [ 1.532169 ] kfence_report_error+0xa4/0x528 [ 1.532276 ] kfence_handle_page_fault+0x124/0x270 [ 1.532388 ] no_context+0x50/0x94 [ 1.532453 ] do_page_fault+0x1a8/0x36c [ 1.532524 ] tlb_do_page_fault_0+0x118/0x1b4 [ 1.532623 ] test_out_of_bounds_read+0xa0/0x1d8 [ 1.532745 ] kunit_generic_run_threadfn_adapter+0x1c/0x28 [ 1.532854 ] kthread+0x124/0x130 [ 1.532922 ] ret_from_kernel_thread+0xc/0xa4 <snip> After this patch: [ 1.320220 ] ================================================================== [ 1.320401 ] BUG: KFENCE: out-of-bounds read in test_out_of_bounds_read+0xa8/0x1d8 [ 1.320401 ] [ 1.320898 ] Out-of-bounds read at 0xffff800012257fff (1B left of kfence-#10): [ 1.321134 ] test_out_of_bounds_read+0xa8/0x1d8 [ 1.321264 ] kunit_generic_run_threadfn_adapter+0x1c/0x28 [ 1.321392 ] kthread+0x124/0x130 [ 1.321459 ] ret_from_kernel_thread+0xc/0xa4 <snip> Suggested-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Enze Li <lienze@kylinos.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Add basic KGDB & KDB supportQing Zhang4-0/+742
KGDB is intended to be used as a source level debugger for the Linux kernel. It is used along with gdb to debug a Linux kernel. GDB can be used to "break in" to the kernel to inspect memory, variables and regs similar to the way an application developer would use GDB to debug an application. KDB is a frontend of KGDB which is similar to GDB. By now, in addition to the generic KGDB features, the LoongArch KGDB implements the following features: - Hardware breakpoints/watchpoints; - Software single-step support for KDB. Signed-off-by: Qing Zhang <zhangqing@loongson.cn> # Framework & CoreFeature Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> # BreakPoint & SingleStep Signed-off-by: Hui Li <lihui@loongson.cn> # Some Minor Improvements Signed-off-by: Randy Dunlap <rdunlap@infradead.org> # Some Build Error Fixes Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Add Loongson Binary Translation (LBT) extension supportQi Hu9-14/+482
Loongson Binary Translation (LBT) is used to accelerate binary translation, which contains 4 scratch registers (scr0 to scr3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop). This patch support kernel to save/restore these registers, handle the LBT exception and maintain sigcontext. Signed-off-by: Qi Hu <huqi@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Allow usage of LSX/LASX in the kernelHuacai Chen1-4/+51
Allow usage of LSX/LASX in the kernel by extending kernel_fpu_begin() and kernel_fpu_end(). Reviewed-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Define symbol 'fault' as a local label in fpu.STiezhu Yang1-3/+2
The initial aim is to silence the following objtool warnings: arch/loongarch/kernel/fpu.o: warning: objtool: _save_fp_context() falls through to next function fault() arch/loongarch/kernel/fpu.o: warning: objtool: _restore_fp_context() falls through to next function fault() arch/loongarch/kernel/fpu.o: warning: objtool: _save_lsx_context() falls through to next function fault() arch/loongarch/kernel/fpu.o: warning: objtool: _restore_lsx_context() falls through to next function fault() arch/loongarch/kernel/fpu.o: warning: objtool: _save_lasx_context() falls through to next function fault() arch/loongarch/kernel/fpu.o: warning: objtool: _restore_lasx_context() falls through to next function fault() Currently, SYM_FUNC_START()/SYM_FUNC_END() defines the symbol 'fault' as SYM_T_FUNC which is STT_FUNC, the objtool warnings are generated through the following code: tools/objtool/include/objtool/check.h: static inline struct symbol *insn_func(struct instruction *insn) { struct symbol *sym = insn->sym; if (sym && sym->type != STT_FUNC) sym = NULL; return sym; } tools/objtool/check.c: static int validate_branch(struct objtool_file *file, struct symbol *func, struct instruction *insn, struct insn_state state) { ... if (func && insn_func(insn) && func != insn_func(insn)->pfunc) { ... WARN("%s() falls through to next function %s()", func->name, insn_func(insn)->name); return 1; } ... } We can see that the fixup can be a local label in the following code: arch/loongarch/include/asm/asm-extable.h: .pushsection __ex_table, "a"; \ .balign 4; \ .long ((insn) - .); \ .long ((fixup) - .); \ .short (type); \ .short (data); \ .popsection; .macro _asm_extable, insn, fixup __ASM_EXTABLE_RAW(\insn, \fixup, EX_TYPE_FIXUP, 0) .endm Like arch/loongarch/lib/*.S, just define the symbol 'fault' as a local label in fpu.S. Before: $ readelf -s arch/loongarch/kernel/fpu.o | awk -F: /fault/'{print $2}' 000000000000053c 8 FUNC GLOBAL DEFAULT 1 fault After: $ readelf -s arch/loongarch/kernel/fpu.o | awk -F: /fault/'{print $2}' 000000000000053c 0 NOTYPE LOCAL DEFAULT 1 .L_fpu_fault Co-developed-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Use static defined zero page rather than allocatedBibo Mao1-1/+0
On LoongArch system, there is only one page needed for zero page (no cache synonyms), and there is no COLOR_ZERO_PAGE, so zero_page_mask is useless and the macro __HAVE_COLOR_ZERO_PAGE is not necessary. Like other popular architectures, It is simpler to define the zero page in kernel BSS code segment rather than dynamically allocate. Signed-off-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: mm: Introduce unified function populate_kernel_pte()Bibo Mao1-35/+1
Function pcpu_populate_pte() and fixmap_pte() are similar, they populate one page from kernel address space. And there is confusion between pgd and p4d in the function fixmap_pte(), such as pgd_none() always returns zero. This patch introduces a unified function populate_kernel_pte() and then replaces pcpu_populate_pte() and fixmap_pte(). Signed-off-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Code improvements in function pcpu_populate_pte()Bibo Mao1-13/+15
Do some code improvements in function pcpu_populate_pte(): 1. Add memory allocation failure handling; 2. Replace pgd_populate() with p4d_populate(), it will be useful if there are four-level page tables. Signed-off-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-26LoongArch: Fix hw_breakpoint_control() for watchpointsHuacai Chen1-2/+1
In hw_breakpoint_control(), encode_ctrl_reg() has already encoded the MWPnCFG3_LoadEn/MWPnCFG3_StoreEn bits in info->ctrl. We don't need to add (1 << MWPnCFG3_LoadEn | 1 << MWPnCFG3_StoreEn) unconditionally. Otherwise we can't set read watchpoint and write watchpoint separately. Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-26LoongArch: Ensure FP/SIMD registers in the core dump file is up to dateHuacai Chen1-0/+4
This is a port of commit 379eb01c21795edb4c ("riscv: Ensure the value of FP registers in the core dump file is up to date"). The values of FP/SIMD registers in the core dump file come from the thread.fpu. However, kernel saves the FP/SIMD registers only before scheduling out the process. If no process switch happens during the exception handling, kernel will not have a chance to save the latest values of FP/SIMD registers. So it may cause their values in the core dump file incorrect. To solve this problem, force fpr_get()/simd_get() to save the FP/SIMD registers into the thread.fpu if the target task equals the current task. Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-25LoongArch: Put the body of play_dead() into arch_cpu_idle_dead()Tiezhu Yang2-8/+1
The initial aim is to silence the following objtool warning: arch/loongarch/kernel/process.o: warning: objtool: arch_cpu_idle_dead() falls through to next function start_thread() According to tools/objtool/Documentation/objtool.txt, this is because the last instruction of arch_cpu_idle_dead() is a call to a noreturn function play_dead(). In order to silence the warning, one simple way is to add the noreturn function play_dead() to objtool's hard-coded global_noreturns array, that is to say, just put "NORETURN(play_dead)" into tools/objtool/noreturns.h, it works well. But I noticed that play_dead() is only defined once and only called by arch_cpu_idle_dead(), so put the body of play_dead() into the caller arch_cpu_idle_dead(), then remove the noreturn function play_dead() is an alternative way which can reduce the overhead of the function call at the same time. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-25LoongArch: Return earlier in die() if notify_die() returns NOTIFY_STOPTiezhu Yang1-2/+4
After the call to oops_exit(), it should not panic or execute the crash kernel if the oops is to be suppressed. Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-25LoongArch: Do not kill the task in die() if notify_die() returns NOTIFY_STOPTiezhu Yang1-6/+6
If notify_die() returns NOTIFY_STOP, honor the return value from the handler chain invocation in die() and return without killing the task as, through a debugger, the fault may have been fixed. It makes sense even if ignoring the event will make the system unstable: by allowing access through a debugger it has been compromised already anyway. It makes our port consistent with x86, arm64, riscv and csky. Commit 20c0d2d44029 ("[PATCH] i386: pass proper trap numbers to die chain handlers") may be the earliest of similar changes. Link: https://lore.kernel.org/r/43DDF02E.76F0.0078.0@novell.com/ Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-25LoongArch: Replace #include <asm/export.h> with #include <linux/export.h>Masahiro Yamada2-2/+2
Commit ddb5cdbafaaad ("kbuild: generate KSYMTAB entries by modpost") deprecated <asm/export.h>, which is now a wrapper of <linux/export.h>. Replace #include <asm/export.h> with #include <linux/export.h>. After all the <asm/export.h> lines are converted, <asm/export.h> and <asm-generic/export.h> will be removed. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-25LoongArch: Remove unneeded #include <asm/export.h>Masahiro Yamada1-1/+0
There is no EXPORT_SYMBOL() line there, hence #include <asm/export.h> is unneeded. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-07-28LoongArch: Fix CMDLINE_EXTEND and CMDLINE_BOOTLOADER handlingZhihong Dong1-0/+16
On FDT systems these command line processing are already taken care of by early_init_dt_scan_chosen(). Add similar handling to the ACPI (non- FDT) code path to allow these config options to work for ACPI (non-FDT) systems too. Signed-off-by: Zhihong Dong <donmor3000@hotmail.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-30Merge tag 'trace-v6.5' of ↵Linus Torvalds3-14/+30
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - Add new feature to have function graph tracer record the return value. Adds a new option: funcgraph-retval ; when set, will show the return value of a function in the function graph tracer. - Also add the option: funcgraph-retval-hex where if it is not set, and the return value is an error code, then it will return the decimal of the error code, otherwise it still reports the hex value. - Add the file /sys/kernel/tracing/osnoise/per_cpu/cpu<cpu>/timerlat_fd That when a application opens it, it becomes the task that the timer lat tracer traces. The application can also read this file to find out how it's being interrupted. - Add the file /sys/kernel/tracing/available_filter_functions_addrs that works just the same as available_filter_functions but also shows the addresses of the functions like kallsyms, except that it gives the address of where the fentry/mcount jump/nop is. This is used by BPF to make it easier to attach BPF programs to ftrace hooks. - Replace strlcpy with strscpy in the tracing boot code. * tag 'trace-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Fix warnings when building htmldocs for function graph retval riscv: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL tracing/boot: Replace strlcpy with strscpy tracing/timerlat: Add user-space interface tracing/osnoise: Skip running osnoise if all instances are off tracing/osnoise: Switch from PF_NO_SETAFFINITY to migrate_disable ftrace: Show all functions with addresses in available_filter_functions_addrs selftests/ftrace: Add funcgraph-retval test case LoongArch: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL x86/ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL arm64: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL tracing: Add documentation for funcgraph-retval and funcgraph-retval-hex function_graph: Support recording and printing the return value of function fgraph: Add declaration of "struct fgraph_ret_regs"
2023-06-30Merge tag 'loongarch-6.5' of ↵Linus Torvalds22-144/+1273
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - preliminary ClangBuiltLinux enablement - add support to clone a time namespace - add vector extensions support - add SMT (Simultaneous Multi-Threading) support - support dbar with different hints - introduce hardware page table walker - add jump-label implementation - add rethook and uprobes support - some bug fixes and other small changes * tag 'loongarch-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (28 commits) LoongArch: Remove five DIE_* definitions in kdebug.h LoongArch: Add uprobes support LoongArch: Use larch_insn_gen_break() for kprobes LoongArch: Add larch_insn_gen_break() to generate break insns LoongArch: Check for AMO instructions in insns_not_supported() LoongArch: Move three functions from kprobes.c to inst.c LoongArch: Replace kretprobe with rethook LoongArch: Add jump-label implementation LoongArch: Select HAVE_DEBUG_KMEMLEAK to support kmemleak LoongArch: Export some arch-specific pm interfaces LoongArch: Introduce hardware page table walker LoongArch: Support dbar with different hints LoongArch: Add SMT (Simultaneous Multi-Threading) support LoongArch: Add vector extensions support LoongArch: Add support to clone a time namespace Makefile: Add loongarch target flag for Clang compilation LoongArch: Mark Clang LTO as working LoongArch: Include KBUILD_CPPFLAGS in CHECKFLAGS invocation LoongArch: vDSO: Use CLANG_FLAGS instead of filtering out '--target=' LoongArch: Tweak CFLAGS for Clang compatibility ...
2023-06-29LoongArch: Add uprobes supportTiezhu Yang3-5/+158
Uprobes is the user-space counterpart to kprobes, this patch adds uprobes support for LoongArch. Here is a simple example with CONFIG_UPROBE_EVENTS=y: # cat test.c #include <stdio.h> int add(int a, int b) { return a + b; } int main() { return add(2, 7); } # gcc test.c -o /tmp/test # nm /tmp/test | grep add 0000000120004194 T add # cd /sys/kernel/debug/tracing # echo > uprobe_events # echo "p:myuprobe /tmp/test:0x4194 %r4 %r5" > uprobe_events # echo "r:myuretprobe /tmp/test:0x4194 %r4" >> uprobe_events # echo 1 > events/uprobes/enable # echo 1 > tracing_on # /tmp/test # cat trace ... # TASK-PID CPU# ||||| TIMESTAMP FUNCTION # | | | ||||| | | test-1060 [001] DNZff 1015.770620: myuprobe: (0x120004194) arg1=0x2 arg2=0x7 test-1060 [001] DNZff 1015.770930: myuretprobe: (0x1200041f0 <- 0x120004194) arg1=0x9 Tested-by: Jeff Xie <xiehuan09@gmail.com> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Use larch_insn_gen_break() for kprobesTiezhu Yang1-19/+14
For now, we can use larch_insn_gen_break() to define KPROBE_BP_INSN and KPROBE_SSTEPBP_INSN. Because larch_insn_gen_break() returns instruction word, define kprobe_opcode_t as u32, then do some small changes related with type conversion, no functional change intended. Tested-by: Jeff Xie <xiehuan09@gmail.com> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Add larch_insn_gen_break() to generate break insnsTiezhu Yang1-0/+14
There exist various break insns such as BRK_KPROBE_BP, BRK_KPROBE_SSTEPBP, BRK_UPROBE_BP and BRK_UPROBE_XOLBP, add larch_insn_gen_break() to generate break insns simpler, this is preparation for later patch. Tested-by: Jeff Xie <xiehuan09@gmail.com> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Check for AMO instructions in insns_not_supported()Tiezhu Yang1-0/+6
Like llsc instructions, the atomic memory access instructions shouldn't be supported for probing, so check for them in insns_not_supported(). Closes: https://lore.kernel.org/all/SY4P282MB351877A70A0333C790FE85A5C09C9@SY4P282MB3518.AUSP282.PROD.OUTLOOK.COM/ Tested-by: Jeff Xie <xiehuan09@gmail.com> Reported-by: Hengqi Chen <hengqi.chen@gmail.com> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Move three functions from kprobes.c to inst.cTiezhu Yang2-44/+41
The three functions insns_not_supported(), insns_need_simulation() and arch_simulate_insn() will be used for uprobes, move them from kprobes.c to inst.c, this is preparation for later patch, no functionality change. Tested-by: Jeff Xie <xiehuan09@gmail.com> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Replace kretprobe with rethookHaoran Jiang5-25/+43
This is an adaptation of commit f3a112c0c40d ("x86,rethook,kprobes: Replace kretprobe with rethook on x86") and commit b57c2f124098 ("riscv: add riscv rethook implementation") to LoongArch. Mainly refer to commit b57c2f124098 ("riscv: add riscv rethook implementation"). Replaces the kretprobe code with rethook on LoongArch. With this patch, kretprobe on LoongArch uses the rethook instead of kretprobe specific trampoline code. Signed-off-by: Haoran Jiang <jianghaoran@kylinos.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Add jump-label implementationYouling Tang2-0/+24
Add support for jump labels based on the ARM64 version. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Introduce hardware page table walkerHuacai Chen2-0/+5
Loongson-3A6000 and newer processors have hardware page table walker (PTW) support. PTW can handle all fastpaths of TLBI/TLBL/TLBS/TLBM exceptions by hardware, software only need to handle slowpaths (page faults). BTW, PTW doesn't append _PAGE_MODIFIED for page table entries, so we change pmd_dirty() and pte_dirty() to also check _PAGE_DIRTY for the "dirty" attribute. Signed-off-by: Liang Gao <gaoliang@loongson.cn> Signed-off-by: Jun Yi <yijun@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Support dbar with different hintsHuacai Chen1-1/+1
Traditionally, LoongArch uses "dbar 0" (full completion barrier) for everything. But the full completion barrier is a performance killer, so Loongson-3A6000 and newer processors have made finer granularity hints available: Bit4: ordering or completion (0: completion, 1: ordering) Bit3: barrier for previous read (0: true, 1: false) Bit2: barrier for previous write (0: true, 1: false) Bit1: barrier for succeeding read (0: true, 1: false) Bit0: barrier for succeeding write (0: true, 1: false) Hint 0x700: barrier for "read after read" from the same address, which is needed by LL-SC loops on old models (dbar 0x700 behaves the same as nop if such reordering is disabled on new models). This patch makes use of the various new hints for different kinds of memory barriers. It brings performance improvements on Loongson-3A6000 series, while not affecting the existing models because all variants are treated as 'dbar 0' there. Why override queued_spin_unlock()? After commit 01e3b958efe85a26d9b ("drivers: Remove explicit invocations of mmiowb()") we need a completion barrier in queued_spin_unlock(), but the generic implementation use smp_store_release() which only provide an ordering barrier. Signed-off-by: Jun Yi <yijun@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Add SMT (Simultaneous Multi-Threading) supportHuacai Chen3-14/+43
Loongson-3A6000 has SMT (Simultaneous Multi-Threading) support, each physical core has two logical cores (threads). This patch add SMT probe and scheduler support via ACPI PPTT. If SCHED_SMT enabled, Loongson-3A6000 is treated as 4 cores, 8 threads; If SCHED_SMT disabled, Loongson-3A6000 is treated as 8 cores, 8 threads. Remove smp_num_siblings to support HMP (Heterogeneous Multi-Processing). Signed-off-by: Liupu Wang <wangliupu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Add vector extensions supportHuacai Chen6-9/+803
Add LoongArch's vector extensions support, which including 128bit LSX (i.e., Loongson SIMD eXtension) and 256bit LASX (i.e., Loongson Advanced SIMD eXtension). Linux kernel doesn't use vector itself, it only handle exceptions and context save/restore. So it only needs a subset of these instructions: * Vector load/store: vld vst vldx vstx xvld xvst xvldx xvstx * 8bit-elements move: vpickve2gr.b xvpickve2gr.b vinsgr2vr.b xvinsgr2vr.b * 16bit-elements move: vpickve2gr.h xvpickve2gr.h vinsgr2vr.h xvinsgr2vr.h * 32bit-elements move: vpickve2gr.w xvpickve2gr.w vinsgr2vr.w xvinsgr2vr.w * 64bit-elements move: vpickve2gr.d xvpickve2gr.d vinsgr2vr.d xvinsgr2vr.d * Elements permute: vpermi.w vpermi.d xvpermi.w xvpermi.d xvpermi.q Introduce AS_HAS_LSX_EXTENSION and AS_HAS_LASX_EXTENSION to avoid non- vector toolchains complains unsupported instructions. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Add support to clone a time namespaceTiezhu Yang2-17/+83
We can see that "Time namespaces are not supported" on LoongArch: (1) clone3 test # cd tools/testing/selftests/clone3 && make && ./clone3 ... # Time namespaces are not supported ok 18 # SKIP Skipping clone3() with CLONE_NEWTIME # Totals: pass:17 fail:0 xfail:0 xpass:0 skip:1 error:0 (2) timens test # cd tools/testing/selftests/timens && make && ./timens ... 1..0 # SKIP Time namespaces are not supported On LoongArch the current kernel does not support CONFIG_TIME_NS which depends on GENERIC_VDSO_TIME_NS, select GENERIC_VDSO_TIME_NS to enable CONFIG_TIME_NS to build kernel/time/namespace.c. Additionally, it needs to define some arch-dependent functions for the timens, such as __arch_get_timens_vdso_data(), arch_get_vdso_data() and vdso_join_timens(). At the same time, modify the layout of vvar to use one page size for generic vdso data, expand another page size for timens vdso data and assign LOONGARCH_VDSO_DATA_SIZE (maybe exceeds a page size if expand in the future) for loongarch vdso data, at last add the callback function vvar_fault() and modify stack_top(). With this patch under CONFIG_TIME_NS: (1) clone3 test # cd tools/testing/selftests/clone3 && make && ./clone3 ... ok 18 [739] Result (0) matches expectation (0) # Totals: pass:18 fail:0 xfail:0 xpass:0 skip:0 error:0 (2) timens test # cd tools/testing/selftests/timens && make && ./timens ... # Totals: pass:10 fail:0 xfail:0 xpass:0 skip:0 error:0 Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Make the CPUCFG&CSR ops simple aliases of compiler built-insWANG Xuerui1-1/+1
In addition to less visual clutter, this also makes Clang happy regarding the const-ness of arguments. In the original approach, all Clang gets to see is the incoming arguments whose const-ness cannot be proven without first being inlined; so Clang errors out here while GCC is fine. While at it, tweak several printk format strings because the return type of csr_read64 becomes effectively unsigned long, instead of unsigned long long. Signed-off-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Calculate various sizes in the linker scriptWANG Rui3-7/+16
Taking the address delta between symbols in different sections is not supported by the LLVM IAS. Instead, do this in the linker script, so the same data can be properly referenced in assembly. Signed-off-by: WANG Rui <wangrui@loongson.cn> Signed-off-by: WANG Xuerui <git@xen0n.name> [chenhuacai: Fix build with !CONFIG_EFI_STUB] Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Add guard for the larch_insn_gen_xxx functionsWANG Rui1-2/+22
Add guard for the larch_insn_gen_xxx functions to verify whether the immediate operand is within the acceptable range. Signed-off-by: WANG Rui <wangrui@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Delete unnecessary debugfs checkingDan Carpenter1-2/+0
Debugfs functions are not supposed to be checked for errors. This is sort of unusual but it is described in the comments for the debugfs_create_dir() function. Also debugfs_create_dir() can never return NULL. Reviewed-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Set CPU#0 as the io master for FDTHuacai Chen1-0/+1
ACPI systems set io masters by parsing ACPI MADT, FDT systems have no MADT so we explicitly set CPU#0 as the io master. Otherwise CPU#0 will be considered as hotpluggable. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-28Merge tag 'sched-core-2023-06-27' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Scheduler SMP load-balancer improvements: - Avoid unnecessary migrations within SMT domains on hybrid systems. Problem: On hybrid CPU systems, (processors with a mixture of higher-frequency SMT cores and lower-frequency non-SMT cores), under the old code lower-priority CPUs pulled tasks from the higher-priority cores if more than one SMT sibling was busy - resulting in many unnecessary task migrations. Solution: The new code improves the load balancer to recognize SMT cores with more than one busy sibling and allows lower-priority CPUs to pull tasks, which avoids superfluous migrations and lets lower-priority cores inspect all SMT siblings for the busiest queue. - Implement the 'runnable boosting' feature in the EAS balancer: consider CPU contention in frequency, EAS max util & load-balance busiest CPU selection. This improves CPU utilization for certain workloads, while leaves other key workloads unchanged. Scheduler infrastructure improvements: - Rewrite the scheduler topology setup code by consolidating it into the build_sched_topology() helper function and building it dynamically on the fly. - Resolve the local_clock() vs. noinstr complications by rewriting the code: provide separate sched_clock_noinstr() and local_clock_noinstr() functions to be used in instrumentation code, and make sure it is all instrumentation-safe. Fixes: - Fix a kthread_park() race with wait_woken() - Fix misc wait_task_inactive() bugs unearthed by the -rt merge: - Fix UP PREEMPT bug by unifying the SMP and UP implementations - Fix task_struct::saved_state handling - Fix various rq clock update bugs, unearthed by turning on the rq clock debugging code. - Fix the PSI WINDOW_MIN_US trigger limit, which was easy to trigger by creating enough cgroups, by removing the warnign and restricting window size triggers to PSI file write-permission or CAP_SYS_RESOURCE. - Propagate SMT flags in the topology when removing degenerate domain - Fix grub_reclaim() calculation bug in the deadline scheduler code - Avoid resetting the min update period when it is unnecessary, in psi_trigger_destroy(). - Don't balance a task to its current running CPU in load_balance(), which was possible on certain NUMA topologies with overlapping groups. - Fix the sched-debug printing of rq->nr_uninterruptible Cleanups: - Address various -Wmissing-prototype warnings, as a preparation to (maybe) enable this warning in the future. - Remove unused code - Mark more functions __init - Fix shadow-variable warnings" * tag 'sched-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) sched/core: Avoid multiple calling update_rq_clock() in __cfsb_csd_unthrottle() sched/core: Avoid double calling update_rq_clock() in __balance_push_cpu_stop() sched/core: Fixed missing rq clock update before calling set_rq_offline() sched/deadline: Update GRUB description in the documentation sched/deadline: Fix bandwidth reclaim equation in GRUB sched/wait: Fix a kthread_park race with wait_woken() sched/topology: Mark set_sched_topology() __init sched/fair: Rename variable cpu_util eff_util arm64/arch_timer: Fix MMIO byteswap sched/fair, cpufreq: Introduce 'runnable boosting' sched/fair: Refactor CPU utilization functions cpuidle: Use local_clock_noinstr() sched/clock: Provide local_clock_noinstr() x86/tsc: Provide sched_clock_noinstr() clocksource: hyper-v: Provide noinstr sched_clock() clocksource: hyper-v: Adjust hv_read_tsc_page_tsc() to avoid special casing U64_MAX x86/vdso: Fix gettimeofday masking math64: Always inline u128 version of mul_u64_u64_shr() s390/time: Provide sched_clock_noinstr() loongarch: Provide noinstr sched_clock_read() ...
2023-06-26Merge tag 'x86-boot-2023-06-26' of ↵Linus Torvalds1-2/+2
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Thomas Gleixner: "Initialize FPU late. Right now FPU is initialized very early during boot. There is no real requirement to do so. The only requirement is to have it done before alternatives are patched. That's done in check_bugs() which does way more than what the function name suggests. So first rename check_bugs() to arch_cpu_finalize_init() which makes it clear what this is about. Move the invocation of arch_cpu_finalize_init() earlier in start_kernel() as it has to be done before fork_init() which needs to know the FPU register buffer size. With those prerequisites the FPU initialization can be moved into arch_cpu_finalize_init(), which removes it from the early and fragile part of the x86 bringup" * tag 'x86-boot-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mem_encrypt: Unbreak the AMD_MEM_ENCRYPT=n build x86/fpu: Move FPU initialization into arch_cpu_finalize_init() x86/fpu: Mark init functions __init x86/fpu: Remove cpuinfo argument from init functions x86/init: Initialize signal frame size late init, x86: Move mem_encrypt_init() into arch_cpu_finalize_init() init: Invoke arch_cpu_finalize_init() earlier init: Remove check_bugs() leftovers um/cpu: Switch to arch_cpu_finalize_init() sparc/cpu: Switch to arch_cpu_finalize_init() sh/cpu: Switch to arch_cpu_finalize_init() mips/cpu: Switch to arch_cpu_finalize_init() m68k/cpu: Switch to arch_cpu_finalize_init() loongarch/cpu: Switch to arch_cpu_finalize_init() ia64/cpu: Switch to arch_cpu_finalize_init() ARM: cpu: Switch to arch_cpu_finalize_init() x86/cpu: Switch to arch_cpu_finalize_init() init: Provide arch_cpu_finalize_init()
2023-06-21LoongArch: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVALDonglin Peng3-14/+30
The previous patch ("function_graph: Support recording and printing the return value of function") has laid the groundwork for the for the funcgraph-retval, and this modification makes it available on the LoongArch platform. We introduce a new structure called fgraph_ret_regs for the LoongArch platform to hold return registers and the frame pointer. We then fill its content in the return_to_handler and pass its address to the function ftrace_return_to_handler to record the return value. Link: https://lkml.kernel.org/r/c5462255e435fab363895c2d7433bc0f5a140411.1680954589.git.pengdonglin@sangfor.com.cn Reviewed-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-16loongarch/cpu: Switch to arch_cpu_finalize_init()Thomas Gleixner1-2/+2
check_bugs() is about to be phased out. Switch over to the new arch_cpu_finalize_init() implementation. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230613224545.195288218@linutronix.de
2023-06-15LoongArch: Fix debugfs_create_dir() error checkingImmad Mir1-1/+1
The debugfs_create_dir() returns ERR_PTR in case of an error and the correct way of checking it is using the IS_ERR_OR_NULL inline function rather than the simple null comparision. This patch fixes the issue. Cc: stable@vger.kernel.org Suggested-By: Ivan Orlov <ivan.orlov0322@gmail.com> Signed-off-by: Immad Mir <mirimmad17@gmail.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-15LoongArch: Avoid uninitialized alignment_maskQing Zhang1-0/+2
The hardware monitoring points for instruction fetching and load/store operations need to align 4 bytes and 1/2/4/8 bytes respectively. Reported-by: Colin King <colin.i.king@gmail.com> Signed-off-by: Qing Zhang <zhangqing@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-15LoongArch: Fix perf event id calculationHuacai Chen1-3/+3
LoongArch PMCFG has 10bit event id rather than 8 bit, so fix it. Cc: stable@vger.kernel.org Signed-off-by: Jun Yi <yijun@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-05loongarch: Provide noinstr sched_clock_read()Peter Zijlstra1-3/+3
With the intent to provide local_clock_noinstr(), a variant of local_clock() that's safe to be called from noinstr code (with the assumption that any such code will already be non-preemptible), prepare for things by providing a noinstr sched_clock_read() function. Specifically, preempt_enable_*() calls out to schedule(), which upsets noinstr validation efforts. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> # Hyper-V Link: https://lore.kernel.org/r/20230519102715.502547082@infradead.org
2023-05-04Merge tag 'loongarch-6.4' of ↵Linus Torvalds9-101/+410
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Better backtraces for humanization - Relay BCE exceptions to userland as SIGSEGV - Provide kernel fpu functions - Optimize memory ops (memset/memcpy/memmove) - Optimize checksum and crc32(c) calculation - Add ARCH_HAS_FORTIFY_SOURCE selection - Add function error injection support - Add ftrace with direct call support - Add basic perf tools support * tag 'loongarch-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (24 commits) tools/perf: Add basic support for LoongArch LoongArch: ftrace: Add direct call trampoline samples support LoongArch: ftrace: Add direct call support LoongArch: ftrace: Implement ftrace_find_callable_addr() to simplify code LoongArch: ftrace: Fix build error if DYNAMIC_FTRACE_WITH_REGS is not set LoongArch: ftrace: Abstract DYNAMIC_FTRACE_WITH_ARGS accesses LoongArch: Add support for function error injection LoongArch: Add ARCH_HAS_FORTIFY_SOURCE selection LoongArch: crypto: Add crc32 and crc32c hw acceleration LoongArch: Add checksum optimization for 64-bit system LoongArch: Optimize memory ops (memset/memcpy/memmove) LoongArch: Provide kernel fpu functions LoongArch: Relay BCE exceptions to userland as SIGSEGV with si_code=SEGV_BNDERR LoongArch: Tweak the BADV and CPUCFG.PRID lines in show_regs() LoongArch: Humanize the ESTAT line when showing registers LoongArch: Humanize the ECFG line when showing registers LoongArch: Humanize the EUEN line when showing registers LoongArch: Humanize the PRMD line when showing registers LoongArch: Humanize the CRMD line when showing registers LoongArch: Fix format of CSR lines during show_regs() ...
2023-05-01LoongArch: ftrace: Add direct call supportYouling Tang2-1/+20
Select the HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS to provide the register_ftrace_direct[_multi] interfaces allowing users to register the customed trampoline (direct_caller) as the mcount for one or more target functions. And modify_ftrace_direct[_multi] are also provided for modifying direct_caller. There are a few cases to distinguish: - If a direct call ops is the only one tracing a function AND the direct called trampoline is within the reach of a 'bl' instruction -> the ftrace patchsite jumps to the trampoline - Else -> the ftrace patchsite jumps to the ftrace_regs_caller trampoline points to ftrace_list_ops so it iterates over all registered ftrace ops, including the direct call ops and calls its call_direct_funcs handler which stores the direct called trampoline's address in the ftrace_regs and the ftrace_regs_caller trampoline will return to that address instead of returning to the traced function Signed-off-by: Qing Zhang <zhangqing@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-05-01LoongArch: ftrace: Implement ftrace_find_callable_addr() to simplify codeYouling Tang1-59/+57
In the module processing functions, the same logic can be reused by implementing ftrace_find_callable_addr(). Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-05-01LoongArch: ftrace: Fix build error if DYNAMIC_FTRACE_WITH_REGS is not setYouling Tang1-3/+1
We can see the following build error if CONFIG_DYNAMIC_FTRACE_WITH_REGS is not set on LoongArch: arch/loongarch/kernel/ftrace_dyn.c: In function ‘ftrace_make_call’: arch/loongarch/kernel/ftrace_dyn.c:167:23: error: implicit declaration of function ‘__get_mod’ 167 | ret = __get_mod(&mod, pc); | ^~~~~~~~~ arch/loongarch/kernel/ftrace_dyn.c:171:24: error: implicit declaration of function ‘get_plt_addr’ 171 | addr = get_plt_addr(mod, addr); | ^~~~~~~~~~~~ The reason is that the __get_mod() and get_plt_addr() may be called in ftrace_make_{call,nop}. Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-05-01LoongArch: Provide kernel fpu functionsHuacai Chen2-1/+44
Provide kernel_fpu_begin()/kernel_fpu_end() to allow the kernel itself to use fpu. They can be used by some other kernel components, e.g., the AMDGPU graphic driver for DCN. Reported-by: WANG Xuerui <kernel@xen0n.name> Tested-by: WANG Xuerui <kernel@xen0n.name> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-05-01LoongArch: Relay BCE exceptions to userland as SIGSEGV with si_code=SEGV_BNDERRWANG Xuerui2-0/+93
SEGV_BNDERR was introduced initially for supporting the Intel MPX, but fell into disuse after the MPX support was removed. The LoongArch bounds-checking instructions behave very differently than MPX, but overall the interface is still kind of suitable for conveying the information to userland when bounds-checking assertions trigger, so we wouldn't have to invent more UAPI. Specifically, when the BCE triggers, a SEGV_BNDERR is sent to userland, with si_addr set to the out-of-bounds address or value (in asrt{gt,le}'s case), and one of si_lower or si_upper set to the configured bound depending on the faulting instruction. The other bound is set to either 0 or ULONG_MAX to resemble a range with both lower and upper bounds. Note that it is possible to have si_addr == si_lower in case of a failing asrtgt or {ld,st}gt, because those instructions test for strict greater-than relationship. This should not pose a problem for userland, though, because the faulting PC is available for the application to associate back to the exact instruction for figuring out the expectation. Example exception context generated by a faulting `asrtgt.d t0, t1` (assert t0 > t1 or BCE) with t0=100 and t1=200: > pc 00005555558206a4 ra 00007ffff2d854fc tp 00007ffff2f2f180 sp 00007ffffbf9fb80 > a0 0000000000000002 a1 00007ffffbf9fce8 a2 00007ffffbf9fd00 a3 00007ffff2ed4558 > a4 0000000000000000 a5 00007ffff2f044c8 a6 00007ffffbf9fce0 a7 fffffffffffff000 > t0 0000000000000064 t1 00000000000000c8 t2 00007ffffbfa2d5e t3 00007ffff2f12aa0 > t4 00007ffff2ed6158 t5 00007ffff2ed6158 t6 000000000000002e t7 0000000003d8f538 > t8 0000000000000005 u0 0000000000000000 s9 0000000000000000 s0 00007ffffbf9fce8 > s1 0000000000000002 s2 0000000000000000 s3 00007ffff2f2c038 s4 0000555555820610 > s5 00007ffff2ed5000 s6 0000555555827e38 s7 00007ffffbf9fd00 s8 0000555555827e38 > ra: 00007ffff2d854fc > ERA: 00005555558206a4 > CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) > PRMD: 00000007 (PPLV3 +PIE -PWE) > EUEN: 00000000 (-FPE -SXE -ASXE -BTE) > ECFG: 0007181c (LIE=2-4,11-12 VS=7) > ESTAT: 000a0000 [BCE] (IS= ECode=10 EsubCode=0) > PRID: 0014c010 (Loongson-64bit, Loongson-3A5000) Signed-off-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-05-01LoongArch: Tweak the BADV and CPUCFG.PRID lines in show_regs()WANG Xuerui1-3/+3
Use ISA manual names for BADV and CPUCFG.PRID lines in show_regs(), for stylistic consistency with the other lines already touched. While at it, also include current CPU's full name in show_regs() output. It may be more helpful for developers looking at the resulting dumps, because multiple distinct CPU models may share the same PRID. Not having this info available may hide problems only found on some but not all of the models sharing one specific PRID. Signed-off-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>