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2020-07-30riscv: Select ARCH_HAS_DEBUG_VM_PGTABLEEmil Renner Berthing1-0/+1
This allows the pgtable tests to be built. Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Use generic pgprot_* macros from <linux/pgtable.h>Pekka Enberg1-6/+0
The <linux/pgtable.h> header now defines generic pgprot_ macros also for the no-MMU configuration, so let's use them. Signed-off-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Cleanup unnecessary define in asm-offset.cGuo Ren2-8/+1
- TASK_THREAD_SP is duplicated define - TASK_STACK is no use at all - Don't worry about thread_info's offset in task_struct, have a look on comment in include/linux/sched.h: struct task_struct { /* * For reasons of header soup (see current_thread_info()), this * must be the first element of task_struct. */ struct thread_info thread_info; Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Add jump-label implementationEmil Renner Berthing8-0/+121
Add jump-label implementation based on the ARM64 version and add CONFIG_JUMP_LABEL=y to the defconfigs. Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> Reviewed-by: Björn Töpel <bjorn.topel@gmail.com> Tested-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Support R_RISCV_ADD64 and R_RISCV_SUB64 relocsEmil Renner Berthing1-0/+16
These are needed for the __jump_table in modules using static keys/jump-labels with the layout from HAVE_ARCH_JUMP_LABEL_RELATIVE on 64bit kernels. Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> Reviewed-by: Björn Töpel <bjorn.topel@gmail.com> Tested-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30Replace HTTP links with HTTPS ones: RISC-VAlexander A. Klimov1-1/+1
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Add STACKPROTECTOR supportedGuo Ren3-0/+40
The -fstack-protector & -fstack-protector-strong features are from gcc. The patch only add basic kernel support to stack-protector feature and some arch could have its own solution such as ARM64_PTR_AUTH. After enabling STACKPROTECTOR and STACKPROTECTOR_STRONG, the .text size is expanded from 0x7de066 to 0x81fb32 (only 5%) to add canary checking code. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Fix typo in asm/hwcap.h uapi headerTobias Klauser1-1/+1
s/userpsace/userspace/ Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Add kmemleak supportTobias Klauser1-0/+1
Tested using syzkaller in QEMU's riscv64 virt machine. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Allow building with kcov coverageTobias Klauser4-0/+7
Add ARCH_HAS_KCOV and HAVE_GCC_PLUGINS to the riscv Kconfig. Also disable instrumentation of some early boot code and vdso. Boot-tested on QEMU's riscv64 virt machine. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Enable context trackingGreentime Hu2-1/+16
This patch implements and enables context tracking for riscv (which is a prerequisite for CONFIG_NO_HZ_FULL support) It adds checking for previous state in the entry that all excepttions and interrupts goes to and calls context_tracking_user_exit() if it comes from user space. It also calls context_tracking_user_enter() if it will return to user space before restore_all. This patch is tested with the dynticks-testing testcase in qemu-system-riscv64 virt machine and Unleashed board. git://git.kernel.org/pub/scm/linux/kernel/git/frederic/dynticks-testing.git We can see the log here. The tick got mostly stopped during the execution of the user loop. _-----=> irqs-off / _----=> need-resched | / _---=> hardirq/softirq || / _--=> preempt-depth ||| / delay TASK-PID CPU# |||| TIMESTAMP FUNCTION | | | |||| | | <idle>-0 [001] d..2 604.183512: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=taskset next_pid=273 next_prio=120 user_loop-273 [001] d.h1 604.184788: hrtimer_expire_entry: hrtimer=000000002eda5fab function=tick_sched_timer now=604176096300 user_loop-273 [001] d.s2 604.184897: workqueue_queue_work: work struct=00000000383402c2 function=vmstat_update workqueue=00000000f36d35d4 req_cpu=1 cpu=1 user_loop-273 [001] dns2 604.185039: tick_stop: success=0 dependency=SCHED user_loop-273 [001] dn.1 604.185103: tick_stop: success=0 dependency=SCHED user_loop-273 [001] d..2 604.185154: sched_switch: prev_comm=taskset prev_pid=273 prev_prio=120 prev_state=R+ ==> next_comm=kworker/1:1 next_pid=46 next_prio=120 <...>-46 [001] .... 604.185194: workqueue_execute_start: work struct 00000000383402c2: function vmstat_update <...>-46 [001] d..2 604.185266: sched_switch: prev_comm=kworker/1:1 prev_pid=46 prev_prio=120 prev_state=I ==> next_comm=taskset next_pid=273 next_prio=120 user_loop-273 [001] d.h1 604.188812: hrtimer_expire_entry: hrtimer=000000002eda5fab function=tick_sched_timer now=604180133400 user_loop-273 [001] d..1 604.189050: tick_stop: success=1 dependency=NONE user_loop-273 [001] d..2 614.251386: sched_switch: prev_comm=user_loop prev_pid=273 prev_prio=120 prev_state=X ==> next_comm=swapper/1 next_pid=0 next_prio=120 <idle>-0 [001] d..2 614.315391: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=taskset next_pid=276 next_prio=120 Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Support irq_work via self IPIsGreentime Hu2-0/+25
Support for arch_irq_work_raise() and arch_irq_work_has_interrupt() was missing from riscv (a prerequisite for FULL_NOHZ). Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Enable LOCKDEP_SUPPORT & fixup TRACE_IRQFLAGS_SUPPORTGuo Ren2-1/+36
Lockdep is needed by proving the spinlocks and rwlocks. To suupport it, we need fixup TRACE_IRQFLAGS_SUPPORT in kernel/entry.S. This patch follow Documentation/irqflags-tracing.txt. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Fixup lockdep_assert_held with wrong param cpu_runningZong Li1-1/+0
The cpu_running is not a lock-class, it lacks the dep_map member in completion. It causes the error as follow: arch/riscv/kernel/smpboot.c: In function '__cpu_up': ./include/linux/lockdep.h:364:52: error: 'struct completion' has no member named 'dep_map' 364 | #define lockdep_is_held(lock) lock_is_held(&(lock)->dep_map) | ^~ ./include/asm-generic/bug.h:113:25: note: in definition of macro 'WARN_ON' 113 | int __ret_warn_on = !!(condition); \ | ^~~~~~~~~ ./include/linux/lockdep.h:390:27: note: in expansion of macro 'lockdep_is_held' 390 | WARN_ON(debug_locks && !lockdep_is_held(l)); \ | ^~~~~~~~~~~~~~~ arch/riscv/kernel/smpboot.c:118:2: note: in expansion of macro 'lockdep_assert_held' 118 | lockdep_assert_held(&cpu_running); There are a lot of archs which use cpu_running in smpboot.c (arm, arm64, openrisc, xtensa, s390, x86, mips), but none of them try lockdep_assert_held(&cpu_running.wait.lock). So Just remove it. Signed-off-by: Zong Li <zong.li@sifive.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Fixup static_obj() failGuo Ren1-1/+1
When enable LOCKDEP, static_obj() will cause error. Because some __initdata static variables is before _stext: static int static_obj(const void *obj) { unsigned long start = (unsigned long) &_stext, end = (unsigned long) &_end, addr = (unsigned long) obj; /* * static variable? */ if ((addr >= start) && (addr < end)) return 1; [ 0.067192] INFO: trying to register non-static key. [ 0.067325] the code is fine but needs lockdep annotation. [ 0.067449] turning off the locking correctness validator. [ 0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44 [ 0.067945] Call Trace: [ 0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4 [ 0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34 [ 0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca [ 0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc [ 0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c [ 0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312 [ 0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a [ 0.069357] [<ffffffe000247c64>] complete+0x1e/0x50 [ 0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a [ 0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2 [ 0.069779] [<ffffffe000001b84>] 0xffffffe000001b84 [ 0.069953] [<ffffffe000001092>] 0xffffffe000001092 static __initdata DECLARE_COMPLETION(kthreadd_done); noinline void __ref rest_init(void) { ... complete(&kthreadd_done); Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-29Merge branch 'locking/header'Peter Zijlstra1-2/+0
2020-07-29locking/atomic: Move ATOMIC_INIT into linux/types.hHerbert Xu1-2/+0
This patch moves ATOMIC_INIT from asm/atomic.h into linux/types.h. This allows users of atomic_t to use ATOMIC_INIT without having to include atomic.h as that way may lead to header loops. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Link: https://lkml.kernel.org/r/20200729123105.GB7047@gondor.apana.org.au
2020-07-27riscv: switch to ->regset_get()Al Viro1-22/+11
Note: riscv_fpr_get() used to forget to zero-pad at the end. Not worth -stable... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-07-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller8-33/+71
The UDP reuseport conflict was a little bit tricky. The net-next code, via bpf-next, extracted the reuseport handling into a helper so that the BPF sk lookup code could invoke it. At the same time, the logic for reuseport handling of unconnected sockets changed via commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace which changed the logic to carry on the reuseport result into the rest of the lookup loop if we do not return immediately. This requires moving the reuseport_has_conns() logic into the callers. While we are here, get rid of inline directives as they do not belong in foo.c files. The other changes were cases of more straightforward overlapping modifications. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-25riscv: Parse all memory blocks to remove unusable memoryAtish Patra1-14/+17
Currently, maximum physical memory allowed is equal to -PAGE_OFFSET. That's why we remove any memory blocks spanning beyond that size. However, it is done only for memblock containing linux kernel which will not work if there are multiple memblocks. Process all memory blocks to figure out how much memory needs to be removed and remove at the end instead of updating the memblock list in place. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-25RISC-V: Do not rely on initrd_start/end computed during early dt parsingAtish Patra1-6/+27
Currently, initrd_start/end are computed during early_init_dt_scan but used during arch_setup. We will get the following panic if initrd is used and CONFIG_DEBUG_VIRTUAL is turned on. [ 0.000000] ------------[ cut here ]------------ [ 0.000000] kernel BUG at arch/riscv/mm/physaddr.c:33! [ 0.000000] Kernel BUG [#1] [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.8.0-rc4-00015-ged0b226fed02 #886 [ 0.000000] epc: ffffffe0002058d2 ra : ffffffe0000053f0 sp : ffffffe001001f40 [ 0.000000] gp : ffffffe00106e250 tp : ffffffe001009d40 t0 : ffffffe00107ee28 [ 0.000000] t1 : 0000000000000000 t2 : ffffffe000a2e880 s0 : ffffffe001001f50 [ 0.000000] s1 : ffffffe0001383e8 a0 : ffffffe00c087e00 a1 : 0000000080200000 [ 0.000000] a2 : 00000000010bf000 a3 : ffffffe00106f3c8 a4 : ffffffe0010bf000 [ 0.000000] a5 : ffffffe000000000 a6 : 0000000000000006 a7 : 0000000000000001 [ 0.000000] s2 : ffffffe00106f068 s3 : ffffffe00106f070 s4 : 0000000080200000 [ 0.000000] s5 : 0000000082200000 s6 : 0000000000000000 s7 : 0000000000000000 [ 0.000000] s8 : 0000000080011010 s9 : 0000000080012700 s10: 0000000000000000 [ 0.000000] s11: 0000000000000000 t3 : 000000000001fe30 t4 : 000000000001fe30 [ 0.000000] t5 : 0000000000000000 t6 : ffffffe00107c471 [ 0.000000] status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003 [ 0.000000] random: get_random_bytes called from print_oops_end_marker+0x22/0x46 with crng_init=0 To avoid the error, initrd_start/end can be computed from phys_initrd_start/size in setup itself. It also improves the initrd placement by aligning the start and size with the page size. Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code") Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-25RISC-V: Set maximum number of mapped pages correctlyAtish Patra1-1/+1
Currently, maximum number of mapper pages are set to the pfn calculated from the memblock size of the memblock containing kernel. This will work until that memblock spans the entire memory. However, it will be set to a wrong value if there are multiple memblocks defined in kernel (e.g. with efi runtime services). Set the the maximum value to the pfn calculated from dram size. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-21bpf, riscv: Use compressed instructions in the rv64 JITLuke Nelson1-134/+147
This patch uses the RVC support and encodings from bpf_jit.h to optimize the rv64 jit. The optimizations work by replacing emit(rv_X(...)) with a call to a helper function emit_X, which will emit a compressed version of the instruction when possible, and when RVC is enabled. The JIT continues to pass all tests in lib/test_bpf.c, and introduces no new failures to test_verifier; both with and without RVC being enabled. Most changes are straightforward replacements of emit(rv_X(...), ctx) with emit_X(..., ctx), with the following exceptions bearing mention; * Change emit_imm to sign-extend the value in "lower", since the checks for RVC (and the instructions themselves) treat the value as signed. Otherwise, small negative immediates will not be recognized as encodable using an RVC instruction. For example, without this change, emit_imm(rd, -1, ctx) would cause lower to become 4095, which is not a 6b int even though a "c.li rd, -1" instruction suffices. * For {BPF_MOV,BPF_ADD} BPF_X, drop using addiw,addw in the 32-bit cases since the values are zero-extended into the upper 32 bits in the following instructions anyways, and the addition commutes with zero-extension. (BPF_SUB BPF_X must still use subw since subtraction does not commute with zero-extension.) This patch avoids optimizing branches and jumps to use RVC instructions since surrounding code often makes assumptions about the sizes of emitted instructions. Optimizing these will require changing these functions (e.g., emit_branch) to dynamically compute jump offsets. The following are examples of the JITed code for the verifier selftest "direct packet read test#3 for CGROUP_SKB OK", without and with RVC enabled, respectively. The former uses 178 bytes, and the latter uses 112, for a ~37% reduction in code size for this example. Without RVC: 0: 02000813 addi a6,zero,32 4: fd010113 addi sp,sp,-48 8: 02813423 sd s0,40(sp) c: 02913023 sd s1,32(sp) 10: 01213c23 sd s2,24(sp) 14: 01313823 sd s3,16(sp) 18: 01413423 sd s4,8(sp) 1c: 03010413 addi s0,sp,48 20: 03056683 lwu a3,48(a0) 24: 02069693 slli a3,a3,0x20 28: 0206d693 srli a3,a3,0x20 2c: 03456703 lwu a4,52(a0) 30: 02071713 slli a4,a4,0x20 34: 02075713 srli a4,a4,0x20 38: 03856483 lwu s1,56(a0) 3c: 02049493 slli s1,s1,0x20 40: 0204d493 srli s1,s1,0x20 44: 03c56903 lwu s2,60(a0) 48: 02091913 slli s2,s2,0x20 4c: 02095913 srli s2,s2,0x20 50: 04056983 lwu s3,64(a0) 54: 02099993 slli s3,s3,0x20 58: 0209d993 srli s3,s3,0x20 5c: 09056a03 lwu s4,144(a0) 60: 020a1a13 slli s4,s4,0x20 64: 020a5a13 srli s4,s4,0x20 68: 00900313 addi t1,zero,9 6c: 006a7463 bgeu s4,t1,0x74 70: 00000a13 addi s4,zero,0 74: 02d52823 sw a3,48(a0) 78: 02e52a23 sw a4,52(a0) 7c: 02952c23 sw s1,56(a0) 80: 03252e23 sw s2,60(a0) 84: 05352023 sw s3,64(a0) 88: 00000793 addi a5,zero,0 8c: 02813403 ld s0,40(sp) 90: 02013483 ld s1,32(sp) 94: 01813903 ld s2,24(sp) 98: 01013983 ld s3,16(sp) 9c: 00813a03 ld s4,8(sp) a0: 03010113 addi sp,sp,48 a4: 00078513 addi a0,a5,0 a8: 00008067 jalr zero,0(ra) With RVC: 0: 02000813 addi a6,zero,32 4: 7179 c.addi16sp sp,-48 6: f422 c.sdsp s0,40(sp) 8: f026 c.sdsp s1,32(sp) a: ec4a c.sdsp s2,24(sp) c: e84e c.sdsp s3,16(sp) e: e452 c.sdsp s4,8(sp) 10: 1800 c.addi4spn s0,sp,48 12: 03056683 lwu a3,48(a0) 16: 1682 c.slli a3,0x20 18: 9281 c.srli a3,0x20 1a: 03456703 lwu a4,52(a0) 1e: 1702 c.slli a4,0x20 20: 9301 c.srli a4,0x20 22: 03856483 lwu s1,56(a0) 26: 1482 c.slli s1,0x20 28: 9081 c.srli s1,0x20 2a: 03c56903 lwu s2,60(a0) 2e: 1902 c.slli s2,0x20 30: 02095913 srli s2,s2,0x20 34: 04056983 lwu s3,64(a0) 38: 1982 c.slli s3,0x20 3a: 0209d993 srli s3,s3,0x20 3e: 09056a03 lwu s4,144(a0) 42: 1a02 c.slli s4,0x20 44: 020a5a13 srli s4,s4,0x20 48: 4325 c.li t1,9 4a: 006a7363 bgeu s4,t1,0x50 4e: 4a01 c.li s4,0 50: d914 c.sw a3,48(a0) 52: d958 c.sw a4,52(a0) 54: dd04 c.sw s1,56(a0) 56: 03252e23 sw s2,60(a0) 5a: 05352023 sw s3,64(a0) 5e: 4781 c.li a5,0 60: 7422 c.ldsp s0,40(sp) 62: 7482 c.ldsp s1,32(sp) 64: 6962 c.ldsp s2,24(sp) 66: 69c2 c.ldsp s3,16(sp) 68: 6a22 c.ldsp s4,8(sp) 6a: 6145 c.addi16sp sp,48 6c: 853e c.mv a0,a5 6e: 8082 c.jr ra Signed-off-by: Luke Nelson <luke.r.nels@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Björn Töpel <bjorn.topel@gmail.com> Link: https://lore.kernel.org/bpf/20200721025241.8077-4-luke.r.nels@gmail.com
2020-07-21bpf, riscv: Add encodings for compressed instructionsLuke Nelson1-0/+452
This patch adds functions for encoding and emitting compressed riscv (RVC) instructions to the BPF JIT. Some regular riscv instructions can be compressed into an RVC instruction if the instruction fields meet some requirements. For example, "add rd, rs1, rs2" can be compressed into "c.add rd, rs2" when rd == rs1. To make using RVC encodings simpler, this patch also adds helper functions that selectively emit either a regular instruction or a compressed instruction if possible. For example, emit_add will produce a "c.add" if possible and regular "add" otherwise. Signed-off-by: Luke Nelson <luke.r.nels@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200721025241.8077-3-luke.r.nels@gmail.com
2020-07-21bpf, riscv: Modify JIT ctx to support compressed instructionsLuke Nelson4-19/+44
This patch makes the necessary changes to struct rv_jit_context and to bpf_int_jit_compile to support compressed riscv (RVC) instructions in the BPF JIT. It changes the JIT image to be u16 instead of u32, since RVC instructions are 2 bytes as opposed to 4. It also changes ctx->offset and ctx->ninsns to refer to 2-byte instructions rather than 4-byte ones. The riscv PC is required to be 16-bit aligned with or without RVC, so this is sufficient to refer to any valid riscv offset. The code for computing jump offsets in bytes is updated accordingly, and factored into a new "ninsns_rvoff" function to simplify the code. Signed-off-by: Luke Nelson <luke.r.nels@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200721025241.8077-2-luke.r.nels@gmail.com
2020-07-21asm/rwonce: Don't pull <asm/barrier.h> into 'asm-generic/rwonce.h'Will Deacon1-0/+1
Now that 'smp_read_barrier_depends()' has gone the way of the Norwegian Blue, drop the inclusion of <asm/barrier.h> in 'asm-generic/rwonce.h'. This requires fixups to some architecture vdso headers which were previously relying on 'asm/barrier.h' coming in via 'linux/compiler.h'. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Will Deacon <will@kernel.org>
2020-07-21riscv: kasan: use local_tlb_flush_all() to avoid uninitialized __sbi_rfenceVincent Chen1-2/+2
It fails to boot the v5.8-rc4 kernel with CONFIG_KASAN because kasan_init and kasan_early_init use uninitialized __sbi_rfence as executing the tlb_flush_all(). Actually, at this moment, only the CPU which is responsible for the system initialization enables the MMU. Other CPUs are parking at the .Lsecondary_start. Hence the tlb_flush_all() is able to be replaced by local_tlb_flush_all() to avoid using uninitialized __sbi_rfence. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-17RISC-V: Upgrade smp_mb__after_spinlock() to iorw,iorwPalmer Dabbelt1-1/+9
While digging through the recent mmiowb preemption issue it came up that we aren't actually preventing IO from crossing a scheduling boundary. While it's a bit ugly to overload smp_mb__after_spinlock() with this behavior, it's what PowerPC is doing so there's some precedent. Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-14riscv: use 16KB kernel stack on 64-bitAndreas Schwab1-0/+4
With the current 8KB stack size there are frequent overflows in a 64-bit configuration. We may split IRQ stacks off in the future, but this fixes a number of issues right now. Signed-off-by: Andreas Schwab <schwab@suse.de> Reviewed-by: Anup Patel <anup@brainfault.org> [Palmer: mention irqstack in the commit text] Fixes: 7db91e57a0ac ("RISC-V: Task implementation") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-10riscv: Avoid kgdb.h including gdb_xml.h to solve unused-const-variable warningVincent Chen2-3/+4
The constant arrays in gdb_xml.h are only used in arch/riscv/kernel/kgdb.c, but other c files may include the gdb_xml.h indirectly via including the kgdb.h. Hence, It will cause many unused-const-variable warnings. This patch makes the kgdb.h not to include the gdb_xml.h to solve this problem. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-10kgdb: Move the extern declaration kgdb_has_hit_break() to generic kgdb.hVincent Chen1-1/+0
Currently, only riscv kgdb.c uses the kgdb_has_hit_break() to identify the kgdb breakpoint. It causes other architectures will encounter the "no previous prototype" warnings if the compile option has W=1. Moving the declaration of extern kgdb_has_hit_break() from risc-v kgdb.h to generic kgdb.h to avoid generating these warnings. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-10riscv: Fix "no previous prototype" compile warning in kgdb.c fileVincent Chen1-5/+5
Some functions are only used in the kgdb.c file. Add static properities to these functions to avoid "no previous prototype" compile warnings Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-10riscv: enable the Kconfig prompt of STRICT_KERNEL_RWXVincent Chen1-0/+2
Due to lack of hardware breakpoint support, the kernel option CONFIG_STRICT_KERNEL_RWX should be disabled when using KGDB. However, CONFIG_STRICT_KERNEL_RWX is always enabled now. Therefore, select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT to enable CONFIG_STRICT_KERNEL_RWX by default, and then select ARCH_OPTIONAL_KERNEL_RWX to enable the Kconfig prompt of CONFIG_STRICT_KERNEL_RWX so that users can turn it off. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-09riscv: Register System RAM as iomem resourcesZong Li1-0/+27
Add System RAM to /proc/iomem, various tools expect it such as kdump. It is also needed for page_is_ram API which checks the specified address whether registered as System RAM in iomem_resource list. Signed-off-by: Zong Li <zong.li@sifive.com> [Palmer: check MEMBLOCK_NOMAP] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-05arch: rename copy_thread_tls() back to copy_thread()Christian Brauner1-2/+2
Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls() back simply copy_thread(). It's a simpler name, and doesn't imply that only tls is copied here. This finishes an outstanding chunk of internal process creation work since we've added clone3(). Cc: linux-arch@vger.kernel.org Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>A Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Greentime Hu <green.hu@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>A Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-07-05arch: remove HAVE_COPY_THREAD_TLSChristian Brauner1-1/+0
All architectures support copy_thread_tls() now, so remove the legacy copy_thread() function and the HAVE_COPY_THREAD_TLS config option. Everyone uses the same process creation calling convention based on copy_thread_tls() and struct kernel_clone_args. This will make it easier to maintain the core process creation code under kernel/, simplifies the callpaths and makes the identical for all architectures. Cc: linux-arch@vger.kernel.org Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Acked-by: Greentime Hu <green.hu@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-06-30RISC-V: Use a local variable instead of smp_processor_id()Greentime Hu1-3/+4
Store the smp_processor_id() in a local variable to save some pointer chasing. Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-30riscv: Select ARCH_SUPPORTS_ATOMIC_RMW by defaultChenxi Mao1-0/+1
Select ARCH_SUPPORTS_ATOMIC_RMW by default to enable osqlocks. Signed-off-by: Chenxi Mao <maochenxi@eswin.com> [Palmer: commit text] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-26riscv: Fixup __vdso_gettimeofday broke dynamic ftraceGuo Ren1-0/+3
For linux-5.8-rc1, enable ftrace of riscv will cause boot panic: [ 2.388980] Run /sbin/init as init process [ 2.529938] init[39]: unhandled signal 4 code 0x1 at 0x0000003ff449e000 [ 2.531078] CPU: 0 PID: 39 Comm: init Not tainted 5.8.0-rc1-dirty #13 [ 2.532719] epc: 0000003ff449e000 ra : 0000003ff449e954 sp : 0000003fffedb900 [ 2.534005] gp : 00000000000e8528 tp : 0000003ff449d800 t0 : 000000000000001e [ 2.534965] t1 : 000000000000000a t2 : 0000003fffedb89e s0 : 0000003fffedb920 [ 2.536279] s1 : 0000003fffedb940 a0 : 0000003ff43d4b2c a1 : 0000000000000000 [ 2.537334] a2 : 0000000000000001 a3 : 0000000000000000 a4 : fffffffffbad8000 [ 2.538466] a5 : 0000003ff449e93a a6 : 0000000000000000 a7 : 0000000000000000 [ 2.539511] s2 : 0000000000000000 s3 : 0000003ff448412c s4 : 0000000000000010 [ 2.541260] s5 : 0000000000000016 s6 : 00000000000d0a30 s7 : 0000003fffedba70 [ 2.542152] s8 : 0000000000000000 s9 : 0000000000000000 s10: 0000003fffedb960 [ 2.543335] s11: 0000000000000000 t3 : 0000000000000000 t4 : 0000003fffedb8a0 [ 2.544471] t5 : 0000000000000000 t6 : 0000000000000000 [ 2.545730] status: 0000000000004020 badaddr: 00000000464c457f cause: 0000000000000002 [ 2.549867] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 [ 2.551267] CPU: 0 PID: 1 Comm: init Not tainted 5.8.0-rc1-dirty #13 [ 2.552061] Call Trace: [ 2.552626] [<ffffffe00020374a>] walk_stackframe+0x0/0xc4 [ 2.553486] [<ffffffe0002039f4>] show_stack+0x40/0x4c [ 2.553995] [<ffffffe00054a6ae>] dump_stack+0x7a/0x98 [ 2.554615] [<ffffffe00020b9b8>] panic+0x114/0x2f4 [ 2.555395] [<ffffffe00020ebd6>] do_exit+0x89c/0x8c2 [ 2.555949] [<ffffffe00020f930>] do_group_exit+0x3a/0x90 [ 2.556715] [<ffffffe000219e08>] get_signal+0xe2/0x6e6 [ 2.557388] [<ffffffe000202d72>] do_notify_resume+0x6a/0x37a [ 2.558089] [<ffffffe000201c16>] ret_from_exception+0x0/0xc "ra:0x3ff449e954" is the return address of "call _mcount" in the prologue of __vdso_gettimeofday(). Without proper relocate, pc jmp to 0x0000003ff449e000 (vdso map base) with a illegal instruction trap. The solution comes from arch/arm64/kernel/vdso/Makefile: CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) - CC_FLAGS_SCS is ShadowCallStack feature in Clang and only implemented for arm64, no use for riscv. Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Cc: stable@vger.kernel.org Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-26riscv: Add extern declarations for vDSO time-related functionsVincent Chen1-0/+6
Add extern declarations for vDSO time-related functions to notify the compiler these functions will be used in somewhere to avoid "no previous prototype" compile warning. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-26riscv: Add -fPIC option to CFLAGS_vgettimeofday.oVincent Chen1-1/+1
The time related vDSO functions use a variable, vdso_data, to access the vDSO data page to get the system time information. Because the vdso_data for CFLAGS_vgettimeofday.o is an external variable defined in vdso.o, the CFLAGS_vgettimeofday.o should be compiled with -fPIC to ensure that vdso_data is addressable. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-20Merge tag 'riscv-for-linus-5.8-rc2' of ↵Linus Torvalds3-6/+22
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - a workaround for a compiler surprise related to the "r" inline assembly that allows LLVM to boot. - a fix to avoid WX-only mappings, which the ISA does not allow. While this probably manifests in many ways, the bug was found in stress-ng. - a missing lock in set_direct_map_*(), which due to a recent lockdep change started asserting. * tag 'riscv-for-linus-5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: RISC-V: Acquire mmap lock before invoking walk_page_range RISC-V: Don't allow write+exec only page mapping request in mmap riscv/atomic: Fix sign extension for RV64I
2020-06-19RISC-V: Acquire mmap lock before invoking walk_page_rangeAtish Patra1-2/+12
As per walk_page_range documentation, mmap lock should be acquired by the caller before invoking walk_page_range. mmap_assert_locked gets triggered without that. The details can be found here. http://lists.infradead.org/pipermail/linux-riscv/2020-June/010335.html Fixes: 395a21ff859c(riscv: add ARCH_HAS_SET_DIRECT_MAP support) Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Michel Lespinasse <walken@google.com> Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-19RISC-V: Don't allow write+exec only page mapping request in mmapYash Shah1-0/+6
As per the table 4.4 of version "20190608-Priv-MSU-Ratified" of the RISC-V instruction set manual[0], the PTE permission bit combination of "write+exec only" is reserved for future use. Hence, don't allow such mapping request in mmap call. An issue is been reported by David Abdurachmanov, that while running stress-ng with "sysbadaddr" argument, RCU stalls are observed on RISC-V specific kernel. This issue arises when the stress-sysbadaddr request for pages with "write+exec only" permission bits and then passes the address obtain from this mmap call to various system call. For the riscv kernel, the mmap call should fail for this particular combination of permission bits since it's not valid. [0]: http://dabbelt.com/~palmer/keep/riscv-isa-manual/riscv-privileged-20190608-1.pdf Signed-off-by: Yash Shah <yash.shah@sifive.com> Reported-by: David Abdurachmanov <david.abdurachmanov@gmail.com> [Palmer: Refer to the latest ISA specification at the only link I could find, and update the terminology.] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-18maccess: rename probe_kernel_address to get_kernel_nofaultChristoph Hellwig2-4/+4
Better describe what this helper does, and match the naming of copy_from_kernel_nofault. Also switch the argument order around, so that it acts and looks like get_user(). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofaultChristoph Hellwig3-5/+6
Better describe what these functions do. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-12riscv/atomic: Fix sign extension for RV64INathan Huckleberry1-4/+4
The argument passed to cmpxchg is not guaranteed to be sign extended, but lr.w sign extends on RV64I. This makes cmpxchg fail on clang built kernels when __old is negative. To fix this, we just cast __old to long which sign extends on RV64I. With this fix, clang built RISC-V kernels now boot. Link: https://github.com/ClangBuiltLinux/linux/issues/867 Signed-off-by: Nathan Huckleberry <nhuck@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-11Merge tag 'riscv-for-linus-5.8-mw1' of ↵Linus Torvalds25-157/+284
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - Kconfig select statements are now sorted alphanumerically - first-level interrupts are now handled via a full irqchip driver - CPU hotplug is fixed - vDSO calls now use the common vDSO infrastructure * tag 'riscv-for-linus-5.8-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: set the permission of vdso_data to read-only riscv: use vDSO common flow to reduce the latency of the time-related functions riscv: fix build warning of missing prototypes RISC-V: Don't mark init section as non-executable RISC-V: Force select RISCV_INTC for CONFIG_RISCV RISC-V: Remove do_IRQ() function clocksource/drivers/timer-riscv: Use per-CPU timer interrupt irqchip: RISC-V per-HART local interrupt controller driver RISC-V: Rename and move plic_find_hart_id() to arch directory RISC-V: self-contained IPI handling routine RISC-V: Sort select statements alphanumerically
2020-06-11riscv: set the permission of vdso_data to read-onlyVincent Chen1-2/+14
The original vdso_data page is empty, so the permission of the vdso_data page can be the same with the vdso text page. After introducing the vDSO common flow, the vdso_data is not empty and the permission should be changed to read-only. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-11riscv: use vDSO common flow to reduce the latency of the time-related functionsVincent Chen16-69/+199
Even if RISC-V has supported the vDSO feature, the latency of the functions for obtaining the system time is still expensive. It is because these functions still trigger a corresponding system call in the process, which slows down the response time. If we want to remove the system call to reduce the latency, the kernel should have the ability to output the system clock information to userspace. This patch introduces the vDSO common flow to enable the kernel to achieve the above feature and uses "rdtime" instruction to obtain the current time in the user space. Under this condition, the latency cost by the ecall from U-mode to S-mode can be eliminated. After applying this patch, the latency of gettimeofday() measured on the HiFive unleashed board can be reduced by %61. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>