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2021-01-14riscv/stacktrace: Fix stack output without ra on the stack topChen Huang
When a function doesn't have a callee, then it will not push ra into the stack, such as lkdtm_BUG() function, addi sp,sp,-16 sd s0,8(sp) addi s0,sp,16 ebreak The struct stackframe use {fp,ra} to get information from stack, if walk_stackframe() with pr_regs, we will obtain wrong value and bad stacktrace, [<ffffffe00066c56c>] lkdtm_BUG+0x6/0x8 ---[ end trace 18da3fbdf08e25d5 ]--- Correct the next fp and pc, after that, full stacktrace shown as expects, [<ffffffe00066c56c>] lkdtm_BUG+0x6/0x8 [<ffffffe0008b24a4>] lkdtm_do_action+0x14/0x1c [<ffffffe00066c372>] direct_entry+0xc0/0x10a [<ffffffe000439f86>] full_proxy_write+0x42/0x6a [<ffffffe000309626>] vfs_write+0x7e/0x214 [<ffffffe00030992a>] ksys_write+0x98/0xc0 [<ffffffe000309960>] sys_write+0xe/0x16 [<ffffffe0002014bc>] ret_from_syscall+0x0/0x2 ---[ end trace 61917f3d9a9fadcd ]--- Signed-off-by: Chen Huang <chenhuang5@huawei.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Improve __show_regsKefeng Wang
Show the function symbols of epc and ra to improve the readability of crash reports, and align the printing formats about the raw epc value. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Add dump stack in show_regsKefeng Wang
Like commit 1149aad10b1e ("arm64: Add dump_backtrace() in show_regs"), dump the stack in riscv show_regs as common code expects. Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Enable per-task stack canariesGuo Ren
This enables the use of per-task stack canary values if GCC has support for emitting the stack canary reference relative to the value of tp, which holds the task struct pointer in the riscv kernel. After compare arm64 and x86 implementations, seems arm64's is more flexible and readable. The key point is how gcc get the offset of stack_canary from gs/el0_sp. x86: Use a fix offset from gs, not flexible. struct fixed_percpu_data { /* * GCC hardcodes the stack canary as %gs:40. Since the * irq_stack is the object at %gs:0, we reserve the bottom * 48 bytes of the irq stack for the canary. */ char gs_base[40]; // :( unsigned long stack_canary; }; arm64: Use -mstack-protector-guard-offset & guard-reg gcc options: -mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=xxx riscv: Use -mstack-protector-guard-offset & guard-reg gcc options: -mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=xxx GCC's implementation has been merged: commit c931e8d5a96463427040b0d11f9c4352ac22b2b0 Author: Cooper Qu <cooper.qu@linux.alibaba.com> Date: Mon Jul 13 16:15:08 2020 +0800 RISC-V: Add support for TLS stack protector canary access In the end, these codes are inserted by gcc before return: * 0xffffffe00020b396 <+120>: ld a5,1008(tp) # 0x3f0 * 0xffffffe00020b39a <+124>: xor a5,a5,a4 * 0xffffffe00020b39c <+126>: mv a0,s5 * 0xffffffe00020b39e <+128>: bnez a5,0xffffffe00020b61c <_do_fork+766> 0xffffffe00020b3a2 <+132>: ld ra,136(sp) 0xffffffe00020b3a4 <+134>: ld s0,128(sp) 0xffffffe00020b3a6 <+136>: ld s1,120(sp) 0xffffffe00020b3a8 <+138>: ld s2,112(sp) 0xffffffe00020b3aa <+140>: ld s3,104(sp) 0xffffffe00020b3ac <+142>: ld s4,96(sp) 0xffffffe00020b3ae <+144>: ld s5,88(sp) 0xffffffe00020b3b0 <+146>: ld s6,80(sp) 0xffffffe00020b3b2 <+148>: ld s7,72(sp) 0xffffffe00020b3b4 <+150>: addi sp,sp,144 0xffffffe00020b3b6 <+152>: ret ... * 0xffffffe00020b61c <+766>: auipc ra,0x7f8 * 0xffffffe00020b620 <+770>: jalr -1764(ra) # 0xffffffe000a02f38 <__stack_chk_fail> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Cooper Qu <cooper.qu@linux.alibaba.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Add uprobes supportedGuo Ren
This patch adds support for uprobes on riscv architecture. Just like kprobe, it support single-step and simulate instructions. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Add KPROBES_ON_FTRACE supportedGuo Ren
This patch adds support for kprobes on ftrace call sites to avoids much of the overhead with regular kprobes. Try it with simple steps: echo 'p:myprobe sys_clone a0=%a0 a1=%a1 stack_val=+4($stack)' > /sys/kernel/de bug/tracing/kprobe_events echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable cat /sys/kernel/debug/tracing/trace tracer: nop entries-in-buffer/entries-written: 1/1 #P:1 _-----=> irqs-off / _----=> need-resched | / _---=> hardirq/softirq || / _--=> preempt-depth ||| / delay TASK-PID CPU# |||| TIMESTAMP FUNCTION | | | |||| | | sh-92 [000] .... 369.899962: myprobe: (sys_clone+0x0/0x28) a0=0x1200011 a1=0x0 stack_val=0x201c20ffffffe0 cat /sys/kernel/debug/kprobes/list ffffffe00020b584 k sys_clone+0x0 [FTRACE] ^^^^^^ Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Add kprobes supportedGuo Ren
This patch enables "kprobe & kretprobe" to work with ftrace interface. It utilized software breakpoint as single-step mechanism. Some instructions which can't be single-step executed must be simulated in kernel execution slot, such as: branch, jal, auipc, la ... Some instructions should be rejected for probing and we use a blacklist to filter, such as: ecall, ebreak, ... We use ebreak & c.ebreak to replace origin instruction and the kprobe handler prepares an executable memory slot for out-of-line execution with a copy of the original instruction being probed. In execution slot we add ebreak behind original instruction to simulate a single-setp mechanism. The patch is based on packi's work [1] and csky's work [2]. - The kprobes_trampoline.S is all from packi's patch - The single-step mechanism is new designed for riscv without hw single-step trap - The simulation codes are from csky - Frankly, all codes refer to other archs' implementation [1] https://lore.kernel.org/linux-riscv/20181113195804.22825-1-me@packi.ch/ [2] https://lore.kernel.org/linux-csky/20200403044150.20562-9-guoren@kernel.org/ Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Patrick Stählin <me@packi.ch> Signed-off-by: Patrick Stählin <me@packi.ch> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Zong Li <zong.li@sifive.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Cc: Patrick Stählin <me@packi.ch> Cc: Palmer Dabbelt <palmerdabbelt@google.com> Cc: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Using PATCHABLE_FUNCTION_ENTRY instead of MCOUNTGuo Ren
This patch changes the current detour mechanism of dynamic ftrace which has been discussed during LPC 2020 RISCV-MC [1]. Before the patch, we used mcount for detour: <funca>: addi sp,sp,-16 sd ra,8(sp) sd s0,0(sp) addi s0,sp,16 mv a5,ra mv a0,a5 auipc ra,0x0 -> nop jalr -296(ra) <_mcount@plt> ->nop ... After the patch, we use nop call site area for detour: <funca>: nop -> REG_S ra, -SZREG(sp) nop -> auipc ra, 0x? nop -> jalr ?(ra) nop -> REG_L ra, -SZREG(sp) ... The mcount mechanism is mixed with gcc function prologue which is not very clear. The patchable function entry just put 16 bytes nop before the front of the function prologue which could be filled with a separated detour mechanism. [1] https://www.linuxplumbersconf.org/event/7/contributions/807/ Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Fixup patch_text panic in ftraceGuo Ren
Just like arm64, we can't trace the function in the patch_text path. Here is the bug log: [ 45.234334] Unable to handle kernel paging request at virtual address ffffffd38ae80900 [ 45.242313] Oops [#1] [ 45.244600] Modules linked in: [ 45.247678] CPU: 0 PID: 11 Comm: migration/0 Not tainted 5.9.0-00025-g9b7db83-dirty #215 [ 45.255797] epc: ffffffe00021689a ra : ffffffe00021718e sp : ffffffe01afabb58 [ 45.262955] gp : ffffffe00136afa0 tp : ffffffe01af94d00 t0 : 0000000000000002 [ 45.270200] t1 : 0000000000000000 t2 : 0000000000000001 s0 : ffffffe01afabc08 [ 45.277443] s1 : ffffffe0013718a8 a0 : 0000000000000000 a1 : ffffffe01afabba8 [ 45.284686] a2 : 0000000000000000 a3 : 0000000000000000 a4 : c4c16ad38ae80900 [ 45.291929] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000052464e43 [ 45.299173] s2 : 0000000000000001 s3 : ffffffe000206a60 s4 : ffffffe000206a60 [ 45.306415] s5 : 00000000000009ec s6 : ffffffe0013718a8 s7 : c4c16ad38ae80900 [ 45.313658] s8 : 0000000000000004 s9 : 0000000000000001 s10: 0000000000000001 [ 45.320902] s11: 0000000000000003 t3 : 0000000000000001 t4 : ffffffffd192fe79 [ 45.328144] t5 : ffffffffb8f80000 t6 : 0000000000040000 [ 45.333472] status: 0000000200000100 badaddr: ffffffd38ae80900 cause: 000000000000000f [ 45.341514] ---[ end trace d95102172248fdcf ]--- [ 45.346176] note: migration/0[11] exited with preempt_count 1 (gdb) x /2i $pc => 0xffffffe00021689a <__do_proc_dointvec+196>: sd zero,0(s7) 0xffffffe00021689e <__do_proc_dointvec+200>: li s11,0 (gdb) bt 0 __do_proc_dointvec (tbl_data=0x0, table=0xffffffe01afabba8, write=0, buffer=0x0, lenp=0x7bf897061f9a0800, ppos=0x4, conv=0x0, data=0x52464e43) at kernel/sysctl.c:581 1 0xffffffe00021718e in do_proc_dointvec (data=<optimized out>, conv=<optimized out>, ppos=<optimized out>, lenp=<optimized out>, buffer=<optimized out>, write=<optimized out>, table=<optimized out>) at kernel/sysctl.c:964 2 proc_dointvec_minmax (ppos=<optimized out>, lenp=<optimized out>, buffer=<optimized out>, write=<optimized out>, table=<optimized out>) at kernel/sysctl.c:964 3 proc_do_static_key (table=<optimized out>, write=1, buffer=0x0, lenp=0x0, ppos=0x7bf897061f9a0800) at kernel/sysctl.c:1643 4 0xffffffe000206792 in ftrace_make_call (rec=<optimized out>, addr=<optimized out>) at arch/riscv/kernel/ftrace.c:109 5 0xffffffe0002c9c04 in __ftrace_replace_code (rec=0xffffffe01ae40c30, enable=3) at kernel/trace/ftrace.c:2503 6 0xffffffe0002ca0b2 in ftrace_replace_code (mod_flags=<optimized out>) at kernel/trace/ftrace.c:2530 7 0xffffffe0002ca26a in ftrace_modify_all_code (command=5) at kernel/trace/ftrace.c:2677 8 0xffffffe0002ca30e in __ftrace_modify_code (data=<optimized out>) at kernel/trace/ftrace.c:2703 9 0xffffffe0002c13b0 in multi_cpu_stop (data=0x0) at kernel/stop_machine.c:224 10 0xffffffe0002c0fde in cpu_stopper_thread (cpu=<optimized out>) at kernel/stop_machine.c:491 11 0xffffffe0002343de in smpboot_thread_fn (data=0x0) at kernel/smpboot.c:165 12 0xffffffe00022f8b4 in kthread (_create=0xffffffe01af0c040) at kernel/kthread.c:292 13 0xffffffe000201fac in handle_exception () at arch/riscv/kernel/entry.S:236 0xffffffe00020678a <+114>: auipc ra,0xffffe 0xffffffe00020678e <+118>: jalr -118(ra) # 0xffffffe000204714 <patch_text_nosync> 0xffffffe000206792 <+122>: snez a0,a0 (gdb) disassemble patch_text_nosync Dump of assembler code for function patch_text_nosync: 0xffffffe000204714 <+0>: addi sp,sp,-32 0xffffffe000204716 <+2>: sd s0,16(sp) 0xffffffe000204718 <+4>: sd ra,24(sp) 0xffffffe00020471a <+6>: addi s0,sp,32 0xffffffe00020471c <+8>: auipc ra,0x0 0xffffffe000204720 <+12>: jalr -384(ra) # 0xffffffe00020459c <patch_insn_write> 0xffffffe000204724 <+16>: beqz a0,0xffffffe00020472e <patch_text_nosync+26> 0xffffffe000204726 <+18>: ld ra,24(sp) 0xffffffe000204728 <+20>: ld s0,16(sp) 0xffffffe00020472a <+22>: addi sp,sp,32 0xffffffe00020472c <+24>: ret 0xffffffe00020472e <+26>: sd a0,-24(s0) 0xffffffe000204732 <+30>: auipc ra,0x4 0xffffffe000204736 <+34>: jalr -1464(ra) # 0xffffffe00020817a <flush_icache_all> 0xffffffe00020473a <+38>: ld a0,-24(s0) 0xffffffe00020473e <+42>: ld ra,24(sp) 0xffffffe000204740 <+44>: ld s0,16(sp) 0xffffffe000204742 <+46>: addi sp,sp,32 0xffffffe000204744 <+48>: ret (gdb) disassemble flush_icache_all-4 Dump of assembler code for function flush_icache_all: 0xffffffe00020817a <+0>: addi sp,sp,-8 0xffffffe00020817c <+2>: sd ra,0(sp) 0xffffffe00020817e <+4>: auipc ra,0xfffff 0xffffffe000208182 <+8>: jalr -1822(ra) # 0xffffffe000206a60 <ftrace_caller> 0xffffffe000208186 <+12>: ld ra,0(sp) 0xffffffe000208188 <+14>: addi sp,sp,8 0xffffffe00020818a <+0>: addi sp,sp,-16 0xffffffe00020818c <+2>: sd s0,0(sp) 0xffffffe00020818e <+4>: sd ra,8(sp) 0xffffffe000208190 <+6>: addi s0,sp,16 0xffffffe000208192 <+8>: li a0,0 0xffffffe000208194 <+10>: auipc ra,0xfffff 0xffffffe000208198 <+14>: jalr -410(ra) # 0xffffffe000206ffa <sbi_remote_fence_i> 0xffffffe00020819c <+18>: ld s0,0(sp) 0xffffffe00020819e <+20>: ld ra,8(sp) 0xffffffe0002081a0 <+22>: addi sp,sp,16 0xffffffe0002081a2 <+24>: ret (gdb) frame 5 (rec=0xffffffe01ae40c30, enable=3) at kernel/trace/ftrace.c:2503 2503 return ftrace_make_call(rec, ftrace_addr); (gdb) p /x rec->ip $2 = 0xffffffe00020817a -> flush_icache_all ! When we modified flush_icache_all's patchable-entry with ftrace_caller: - Insert ftrace_caller at flush_icache_all prologue. - Call flush_icache_all to sync I/Dcache, but flush_icache_all is just we modified by half. Link: https://lore.kernel.org/linux-riscv/CAJF2gTT=oDWesWe0JVWvTpGi60-gpbNhYLdFWN_5EbyeqoEDdw@mail.gmail.com/T/#t Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Fixup wrong ftrace remove cflagGuo Ren
We must use $(CC_FLAGS_FTRACE) instead of directly using -pg. It will cause -fpatchable-function-entry error. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Fixup compile error BUILD_BUG_ON failedGuo Ren
Unfortunately, the current code couldn't be compiled: CC arch/riscv/kernel/patch.o In file included from ./include/linux/kernel.h:11, from ./include/linux/list.h:9, from ./include/linux/preempt.h:11, from ./include/linux/spinlock.h:51, from arch/riscv/kernel/patch.c:6: In function ‘fix_to_virt’, inlined from ‘patch_map’ at arch/riscv/kernel/patch.c:37:17: ./include/linux/compiler.h:392:38: error: call to ‘__compiletime_assert_205’ declared with attribute error: BUILD_BUG_ON failed: idx >= __end_of_fixed_addresses _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ ./include/linux/compiler.h:373:4: note: in definition of macro ‘__compiletime_assert’ prefix ## suffix(); \ ^~~~~~ ./include/linux/compiler.h:392:2: note: in expansion of macro ‘_compiletime_assert’ _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^~~~~~~~~~~~~~~~~~~ ./include/linux/build_bug.h:39:37: note: in expansion of macro ‘compiletime_assert’ #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^~~~~~~~~~~~~~~~~~ ./include/linux/build_bug.h:50:2: note: in expansion of macro ‘BUILD_BUG_ON_MSG’ BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) ^~~~~~~~~~~~~~~~ ./include/asm-generic/fixmap.h:32:2: note: in expansion of macro ‘BUILD_BUG_ON’ BUILD_BUG_ON(idx >= __end_of_fixed_addresses); ^~~~~~~~~~~~ Because fix_to_virt(, idx) needs a const value, not a dynamic variable of reg-a0 or BUILD_BUG_ON failed with "idx >= __end_of_fixed_addresses". Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14RISC-V: Implement ptrace regs and stack APIPatrick Stählin
Needed for kprobes support. Copied and adapted from arm64 code. Guo Ren fixup pt_regs type for linux-5.8-rc1. Signed-off-by: Patrick Stählin <me@packi.ch> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Reviewed-by: Zong Li <zong.li@sifive.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Add machine name to kernel boot log and stack dump outputKefeng Wang
Add the machine name to kernel boot-up log, and install the machine name to stack dump for DT boot mode. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Add numa support for riscv64 platformAtish Patra
Use the generic numa implementation to add NUMA support for RISC-V. This is based on Greentime's patch[1] but modified to use generic NUMA implementation and few more fixes. [1] https://lkml.org/lkml/2020/1/10/233 Co-developed-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14riscv: Separate memory init from paging initAtish Patra
Currently, we perform some memory init functions in paging init. But, that will be an issue for NUMA support where DT needs to be flattened before numa initialization and memblock_present can only be called after numa initialization. Move memory initialization related functions to a separate function. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-12riscv: Fixup CONFIG_GENERIC_TIME_VSYSCALLGuo Ren
The patch fix commit: ad5d112 ("riscv: use vDSO common flow to reduce the latency of the time-related functions"). The GENERIC_TIME_VSYSCALL should be CONFIG_GENERIC_TIME_VSYSCALL or vgettimeofday won't work. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-12riscv: cacheinfo: Fix using smp_processor_id() in preemptibleKefeng Wang
Use raw_smp_processor_id instead of smp_processor_id() to fix warning, BUG: using smp_processor_id() in preemptible [00000000] code: init/1 caller is debug_smp_processor_id+0x1c/0x26 CPU: 0 PID: 1 Comm: init Not tainted 5.10.0-rc4 #211 Call Trace: walk_stackframe+0x0/0xaa show_stack+0x32/0x3e dump_stack+0x76/0x90 check_preemption_disabled+0xaa/0xac debug_smp_processor_id+0x1c/0x26 get_cache_size+0x18/0x68 load_elf_binary+0x868/0xece bprm_execve+0x224/0x498 kernel_execve+0xdc/0x142 run_init_process+0x90/0x9e try_to_run_init_process+0x12/0x3c kernel_init+0xb4/0xf8 ret_from_exception+0x0/0xc The issue is found when CONFIG_DEBUG_PREEMPT enabled. Reviewed-by: Atish Patra <atish.patra@wdc.com> Tested-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> [Palmer: Added a comment.] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-12riscv: Trace irq on only interrupt is enabledAtish Patra
We should call irq trace only if interrupt is going to be enabled during excecption handling. Otherwise, it results in following warning during boot with lock debugging enabled. [ 0.000000] ------------[ cut here ]------------ [ 0.000000] DEBUG_LOCKS_WARN_ON(early_boot_irqs_disabled) [ 0.000000] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:4085 lockdep_hardirqs_on_prepare+0x22a/0x22e [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.10.0-00022-ge20097fb37e2-dirty #548 [ 0.000000] epc: c005d5d4 ra : c005d5d4 sp : c1c01e80 [ 0.000000] gp : c1d456e0 tp : c1c0a980 t0 : 00000000 [ 0.000000] t1 : ffffffff t2 : 00000000 s0 : c1c01ea0 [ 0.000000] s1 : c100f360 a0 : 0000002d a1 : c00666ee [ 0.000000] a2 : 00000000 a3 : 00000000 a4 : 00000000 [ 0.000000] a5 : 00000000 a6 : c1c6b390 a7 : 3ffff00e [ 0.000000] s2 : c2384fe8 s3 : 00000000 s4 : 00000001 [ 0.000000] s5 : c1c0a980 s6 : c1d48000 s7 : c1613b4c [ 0.000000] s8 : 00000fff s9 : 80000200 s10: c1613b40 [ 0.000000] s11: 00000000 t3 : 00000000 t4 : 00000000 [ 0.000000] t5 : 00000001 t6 : 00000000 Fixes: 3c4697982982 ("riscv:Enable LOCKDEP_SUPPORT & fixup TRACE_IRQFLAGS_SUPPORT") Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07riscv: Fix builtin DTB handlingDamien Le Moal
All SiPeed K210 MAIX boards have the exact same vendor, arch and implementation IDs, preventing differentiation to select the correct device tree to use through the SOC_BUILTIN_DTB_DECLARE() macro. This result in this macro to be useless and mandates changing the code of the sysctl driver to change the builtin device tree suitable for the target board. Fix this problem by removing the SOC_BUILTIN_DTB_DECLARE() macro since it is used only for the K210 support. The code searching the builtin DTBs using the vendor, arch an implementation IDs is also removed. Support for builtin DTB falls back to the simpler and more traditional handling of builtin DTB using the CONFIG_BUILTIN_DTB option, similarly to other architectures. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07riscv: Enable interrupts during syscalls with M-ModeDamien Le Moal
When running is M-Mode (no MMU config), MPIE does not get set. This results in all syscalls being executed with interrupts disabled as handle_exception never sets SR_IE as it always sees SR_PIE being cleared. Fix this by always force enabling interrupts in handle_syscall when CONFIG_RISCV_M_MODE is enabled. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07riscv: Fix kernel time_init()Damien Le Moal
If of_clk_init() is not called in time_init(), clock providers defined in the system device tree are not initialized, resulting in failures for other devices to initialize due to missing clocks. Similarly to other architectures and to the default kernel time_init() implementation, call of_clk_init() before executing timer_probe() in time_init(). Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Acked-by: Stephen Boyd <sboyd@kernel.org> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07riscv: return -ENOSYS for syscall -1Andreas Schwab
Properly return -ENOSYS for syscall -1 instead of leaving the return value uninitialized. This fixes the strace teststuite. Fixes: 5340627e3fe0 ("riscv: add support for SECCOMP and SECCOMP_FILTER") Cc: stable@vger.kernel.org Signed-off-by: Andreas Schwab <schwab@suse.de> Reviewed-by: Tycho Andersen <tycho@tycho.pizza> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07riscv: Cleanup sbi function stubs when RISCV_SBI disabledKefeng Wang
Fix sbi_init() function declaration mismatch between RISCV_SBI enable and disable, as it always returned 0, make it void function. Drop some stubs which won't be used if RISCV_SBI disabled. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-18Merge tag 'riscv-for-linus-5.11-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "We have a handful of new kernel features for 5.11: - Support for the contiguous memory allocator. - Support for IRQ Time Accounting - Support for stack tracing - Support for strict /dev/mem - Support for kernel section protection I'm being a bit conservative on the cutoff for this round due to the timing, so this is all the new development I'm going to take for this cycle (even if some of it probably normally would have been OK). There are, however, some fixes on the list that I will likely be sending along either later this week or early next week. There is one issue in here: one of my test configurations (PREEMPT{,_DEBUG}=y) fails to boot on QEMU 5.0.0 (from April) as of the .text.init alignment patch. With any luck we'll sort out the issue, but given how many bugs get fixed all over the place and how unrelated those features seem my guess is that we're just running into something that's been lurking for a while and has already been fixed in the newer QEMU (though I wouldn't be surprised if it's one of these implicit assumptions we have in the boot flow). If it was hardware I'd be strongly inclined to look more closely, but given that users can upgrade their simulators I'm less worried about it" * tag 'riscv-for-linus-5.11-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: arm64: Use the generic devmem_is_allowed() arm: Use the generic devmem_is_allowed() RISC-V: Use the new generic devmem_is_allowed() lib: Add a generic version of devmem_is_allowed() riscv: Fixed kernel test robot warning riscv: kernel: Drop unused clean rule riscv: provide memmove implementation RISC-V: Move dynamic relocation section under __init RISC-V: Protect all kernel sections including init early RISC-V: Align the .init.text section RISC-V: Initialize SBI early riscv: Enable ARCH_STACKWALK riscv: Make stack walk callback consistent with generic code riscv: Cleanup stacktrace riscv: Add HAVE_IRQ_TIME_ACCOUNTING riscv: Enable CMA support riscv: Ignore Image.* and loader.bin riscv: Clean up boot dir riscv: Fix compressed Image formats build RISC-V: Add kernel image sections to the resource tree
2020-12-16Merge tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull TIF_NOTIFY_SIGNAL updates from Jens Axboe: "This sits on top of of the core entry/exit and x86 entry branch from the tip tree, which contains the generic and x86 parts of this work. Here we convert the rest of the archs to support TIF_NOTIFY_SIGNAL. With that done, we can get rid of JOBCTL_TASK_WORK from task_work and signal.c, and also remove a deadlock work-around in io_uring around knowing that signal based task_work waking is invoked with the sighand wait queue head lock. The motivation for this work is to decouple signal notify based task_work, of which io_uring is a heavy user of, from sighand. The sighand lock becomes a huge contention point, particularly for threaded workloads where it's shared between threads. Even outside of threaded applications it's slower than it needs to be. Roman Gershman <romger@amazon.com> reported that his networked workload dropped from 1.6M QPS at 80% CPU to 1.0M QPS at 100% CPU after io_uring was changed to use TIF_NOTIFY_SIGNAL. The time was all spent hammering on the sighand lock, showing 57% of the CPU time there [1]. There are further cleanups possible on top of this. One example is TIF_PATCH_PENDING, where a patch already exists to use TIF_NOTIFY_SIGNAL instead. Hopefully this will also lead to more consolidation, but the work stands on its own as well" [1] https://github.com/axboe/liburing/issues/215 * tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block: (28 commits) io_uring: remove 'twa_signal_ok' deadlock work-around kernel: remove checking for TIF_NOTIFY_SIGNAL signal: kill JOBCTL_TASK_WORK io_uring: JOBCTL_TASK_WORK is no longer used by task_work task_work: remove legacy TWA_SIGNAL path sparc: add support for TIF_NOTIFY_SIGNAL riscv: add support for TIF_NOTIFY_SIGNAL nds32: add support for TIF_NOTIFY_SIGNAL ia64: add support for TIF_NOTIFY_SIGNAL h8300: add support for TIF_NOTIFY_SIGNAL c6x: add support for TIF_NOTIFY_SIGNAL alpha: add support for TIF_NOTIFY_SIGNAL xtensa: add support for TIF_NOTIFY_SIGNAL arm: add support for TIF_NOTIFY_SIGNAL microblaze: add support for TIF_NOTIFY_SIGNAL hexagon: add support for TIF_NOTIFY_SIGNAL csky: add support for TIF_NOTIFY_SIGNAL openrisc: add support for TIF_NOTIFY_SIGNAL sh: add support for TIF_NOTIFY_SIGNAL um: add support for TIF_NOTIFY_SIGNAL ...
2020-12-12riscv: add support for TIF_NOTIFY_SIGNALJens Axboe
Wire up TIF_NOTIFY_SIGNAL handling for riscv. Cc: linux-riscv@lists.infradead.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-10riscv: Fixed kernel test robot warningSouptick Joarder
Kernel test robot throws below warning - arch/riscv/kernel/asm-offsets.c:14:6: warning: no previous prototype for 'asm_offsets' [-Wmissing-prototypes] 14 | void asm_offsets(void) | ^~~~~~~~~~~ This patch should fixed it. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-10riscv: kernel: Drop unused clean ruleKefeng Wang
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-10riscv: provide memmove implementationNylon Chen
The memmove used by the kernel feature like KASAN. Signed-off-by: Nick Hu <nickhu@andestech.com> Signed-off-by: Nick Hu <nick650823@gmail.com> Signed-off-by: Nylon Chen <nylon7@andestech.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-29Merge tag 'locking-urgent-2020-11-29' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "Two more places which invoke tracing from RCU disabled regions in the idle path. Similar to the entry path the low level idle functions have to be non-instrumentable" * tag 'locking-urgent-2020-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: intel_idle: Fix intel_idle() vs tracing sched/idle: Fix arch_cpu_idle() vs tracing
2020-11-25RISC-V: Move dynamic relocation section under __initAtish Patra
Dynamic relocation section are only required during boot. Those sections can be freed after init. Thus, it can be moved to __init section. Signed-off-by: Atish Patra <atish.patra@wdc.com> Tested-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25RISC-V: Protect all kernel sections including init earlyAtish Patra
Currently, .init.text & .init.data are intermixed which makes it impossible apply different permissions to them. .init.data shouldn't need exec permissions while .init.text shouldn't have write permission. Moreover, the strict permission are only enforced /init starts. This leaves the kernel vulnerable from possible buggy built-in modules. Keep .init.text & .data in separate sections so that different permissions are applied to each section. Apply permissions to individual sections as early as possible. This improves the kernel protection under CONFIG_STRICT_KERNEL_RWX. We also need to restore the permissions for the entire _init section after it is freed so that those pages can be used for other purpose. Signed-off-by: Atish Patra <atish.patra@wdc.com> Tested-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25RISC-V: Align the .init.text sectionAtish Patra
In order to improve kernel text protection, we need separate .init.text/ .init.data/.text in separate sections. However, RISC-V linker relaxation code is not aware of any alignment between sections. As a result, it may relax any RISCV_CALL relocations between sections to JAL without realizing that an inter section alignment may move the address farther. That may lead to a relocation truncated fit error. However, linker relaxation code is aware of the individual section alignments. The detailed discussion on this issue can be found here. https://github.com/riscv/riscv-gnu-toolchain/issues/738 Keep the .init.text section aligned so that linker relaxation will take that as a hint while relaxing inter section calls. Here are the code size changes for each section because of this change. section change in size (in bytes) .head.text +4 .text +40 .init.text +6530 .exit.text +84 The only significant increase in size happened for .init.text because all intra relocations also use 2MB alignment. Suggested-by: Jim Wilson <jimw@sifive.com> Signed-off-by: Atish Patra <atish.patra@wdc.com> Tested-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25RISC-V: Initialize SBI earlyAtish Patra
Currently, SBI is initialized towards the end of arch setup. This prevents the set memory operations to be invoked earlier as it requires a full tlb flush. Initialize SBI as early as possible. Signed-off-by: Atish Patra <atish.patra@wdc.com> Tested-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25riscv: Enable ARCH_STACKWALKKefeng Wang
Convert to ARCH_STACKWALK to reduce duplicated code in stack trace. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25RISC-V: Add missing jump label initializationAnup Patel
The jump_label_init() should be called from setup_arch() very early for proper functioning of jump label support. Fixes: ebc00dde8a97 ("riscv: Add jump-label implementation") Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25riscv: Explicitly specify the build id style in vDSO Makefile againNathan Chancellor
Commit a96843372331 ("kbuild: explicitly specify the build id style") explicitly set the build ID style to SHA1. Commit c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+") undid this change, likely unintentionally. Restore it so that the build ID style stays consistent across the tree regardless of linker. Fixes: c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+") Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Bill Wendling <morbo@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-24sched/idle: Fix arch_cpu_idle() vs tracingPeter Zijlstra
We call arch_cpu_idle() with RCU disabled, but then use local_irq_{en,dis}able(), which invokes tracing, which relies on RCU. Switch all arch_cpu_idle() implementations to use raw_local_irq_{en,dis}able() and carefully manage the lockdep,rcu,tracing state like we do in entry. (XXX: we really should change arch_cpu_idle() to not return with interrupts enabled) Reported-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
2020-11-20riscv: Make stack walk callback consistent with generic codeKefeng Wang
In order to use generic arch_stack_walk() code, make stack walk callback consistent with it. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-20riscv: Cleanup stacktraceKefeng Wang
1. add asm/stacktrace.h for walk_stackframe and struct stackframe 2. remove unnecessary blank lines in stacktrace.c 3. fix warning "no previous prototype for ‘fill_callchain’" Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-15Merge tag 'perf-urgent-2020-11-15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "A set of fixes for perf: - A set of commits which reduce the stack usage of various perf event handling functions which allocated large data structs on stack causing stack overflows in the worst case - Use the proper mechanism for detecting soft interrupts in the recursion protection - Make the resursion protection simpler and more robust - Simplify the scheduling of event groups to make the code more robust and prepare for fixing the issues vs. scheduling of exclusive event groups - Prevent event multiplexing and rotation for exclusive event groups - Correct the perf event attribute exclusive semantics to take pinned events, e.g. the PMU watchdog, into account - Make the anythread filtering conditional for Intel's generic PMU counters as it is not longer guaranteed to be supported on newer CPUs. Check the corresponding CPUID leaf to make sure - Fixup a duplicate initialization in an array which was probably caused by the usual 'copy & paste - forgot to edit' mishap" * tag 'perf-urgent-2020-11-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/uncore: Fix Add BW copypasta perf/x86/intel: Make anythread filter support conditional perf: Tweak perf_event_attr::exclusive semantics perf: Fix event multiplexing for exclusive groups perf: Simplify group_sched_in() perf: Simplify group_sched_out() perf/x86: Make dummy_iregs static perf/arch: Remove perf_sample_data::regs_user_copy perf: Optimize get_recursion_context() perf: Fix get_recursion_context() perf/x86: Reduce stack usage for x86_pmu::drain_pebs() perf: Reduce stack usage of perf_output_begin()
2020-11-09RISC-V: Add kernel image sections to the resource treeNick Kossifidis
This patch (previously part of my kexec/kdump series) populates /proc/iomem with the various sections of the kernel image. We need this for kexec-tools to be able to prepare the crashkernel image for kdump to work. Since resource tree initialization is not related to memory initialization I added the code to kernel/setup.c and removed the original code (derived from the arm64 tree) from mm/init.c. Signed-off-by: Nick Kossifidis <mick@ics.forth.gr> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-09perf/arch: Remove perf_sample_data::regs_user_copyPeter Zijlstra
struct perf_sample_data lives on-stack, we should be careful about it's size. Furthermore, the pt_regs copy in there is only because x86_64 is a trainwreck, solve it differently. Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Steven Rostedt <rostedt@goodmis.org> Link: https://lkml.kernel.org/r/20201030151955.258178461@infradead.org
2020-11-06RISC-V: Fix the VDSO symbol generaton for binutils-2.35+Palmer Dabbelt
We were relying on GNU ld's ability to re-link executable files in order to extract our VDSO symbols. This behavior was deemed a bug as of binutils-2.35 (specifically the binutils-gdb commit a87e1817a4 ("Have the linker fail if any attempt to link in an executable is made."), but as that has been backported to at least Debian's binutils-2.34 in may manifest in other places. The previous version of this was a bit of a mess: we were linking a static executable version of the VDSO, containing only a subset of the input symbols, which we then linked into the kernel. This worked, but certainly wasn't a supported path through the toolchain. Instead this new version parses the textual output of nm to produce a symbol table. Both rely on near-zero addresses being linkable, but as we rely on weak undefined symbols being linkable elsewhere I don't view this as a major issue. Fixes: e2c0cdfba7f6 ("RISC-V: User-facing API") Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-05riscv: Set text_offset correctly for M-ModeSean Anderson
M-Mode Linux is loaded at the start of RAM, not 2MB later. Perhaps this should be calculated based on PAGE_OFFSET somehow? Even better would be to deprecate text_offset and instead introduce something absolute. Signed-off-by: Sean Anderson <seanga2@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-04risc-v: kernel: ftrace: Fixes improper SPDX comment styleRyan Kosta
Signed-off-by: Ryan Kosta <ryanpkosta@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches
Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-24Merge tag 'riscv-for-linus-5.10-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: "Just a single patch set: the remainder of Christoph's work to remove set_fs, including the RISC-V portion" * tag 'riscv-for-linus-5.10-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: remove address space overrides using set_fs() riscv: implement __get_kernel_nofault and __put_user_nofault riscv: refactor __get_user and __put_user riscv: use memcpy based uaccess for nommu again asm-generic: make the set_fs implementation optional asm-generic: add nommu implementations of __{get,put}_kernel_nofault asm-generic: improve the nommu {get,put}_user handling uaccess: provide a generic TASK_SIZE_MAX definition
2020-10-23Merge tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull arch task_work cleanups from Jens Axboe: "Two cleanups that don't fit other categories: - Finally get the task_work_add() cleanup done properly, so we don't have random 0/1/false/true/TWA_SIGNAL confusing use cases. Updates all callers, and also fixes up the documentation for task_work_add(). - While working on some TIF related changes for 5.11, this TIF_NOTIFY_RESUME cleanup fell out of that. Remove some arch duplication for how that is handled" * tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block: task_work: cleanup notification modes tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume()
2020-10-22Merge tag 'kbuild-v5.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Support 'make compile_commands.json' to generate the compilation database more easily, avoiding stale entries - Support 'make clang-analyzer' and 'make clang-tidy' for static checks using clang-tidy - Preprocess scripts/modules.lds.S to allow CONFIG options in the module linker script - Drop cc-option tests from compiler flags supported by our minimal GCC/Clang versions - Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y - Use sha1 build id for both BFD linker and LLD - Improve deb-pkg for reproducible builds and rootless builds - Remove stale, useless scripts/namespace.pl - Turn -Wreturn-type warning into error - Fix build error of deb-pkg when CONFIG_MODULES=n - Replace 'hostname' command with more portable 'uname -n' - Various Makefile cleanups * tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits) kbuild: Use uname for LINUX_COMPILE_HOST detection kbuild: Only add -fno-var-tracking-assignments for old GCC versions kbuild: remove leftover comment for filechk utility treewide: remove DISABLE_LTO kbuild: deb-pkg: clean up package name variables kbuild: deb-pkg: do not build linux-headers package if CONFIG_MODULES=n kbuild: enforce -Werror=return-type scripts: remove namespace.pl builddeb: Add support for all required debian/rules targets builddeb: Enable rootless builds builddeb: Pass -n to gzip for reproducible packages kbuild: split the build log of kallsyms kbuild: explicitly specify the build id style scripts/setlocalversion: make git describe output more reliable kbuild: remove cc-option test of -Werror=date-time kbuild: remove cc-option test of -fno-stack-check kbuild: remove cc-option test of -fno-strict-overflow kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles kbuild: remove redundant CONFIG_KASAN check from scripts/Makefile.kasan kbuild: do not create built-in objects for external module builds ...