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2021-06-10riscv: xip: support runtime trap patchingVitaly Wool2-5/+23
RISCV_ERRATA_ALTERNATIVE patches text at runtime which is currently not possible when the kernel is executed from the flash in XIP mode. Since runtime patching concerns only traps at the moment, let's just have all the traps reside in RAM anyway if RISCV_ERRATA_ALTERNATIVE is set. Thus, these functions will be patch-able even when the .text section is in flash. Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-06-01RISC-V: Fix memblock_free() usages in init_resources()Wende Tan1-2/+2
`memblock_free()` takes a physical address as its first argument. Fix the wrong usages in `init_resources()`. Fixes: ffe0e526126884cf036a6f724220f1f9b4094fd2 ("RISC-V: Improve init_resources()") Fixes: 797f0375dd2ef5cdc68ac23450cbae9a5c67a74e ("RISC-V: Do not allocate memblock while iterating reserved memblocks") Signed-off-by: Wende Tan <twd2.me@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-22riscv: kexec: Fix W=1 build warningsJisheng Zhang1-5/+6
Fixes the following W=1 build warning(s): In file included from include/linux/kexec.h:28, from arch/riscv/kernel/machine_kexec.c:7: arch/riscv/include/asm/kexec.h:45:1: warning: ‘extern’ is not at beginning of declaration [-Wold-style-declaration] 45 | const extern unsigned char riscv_kexec_relocate[]; | ^~~~~ arch/riscv/include/asm/kexec.h:46:1: warning: ‘extern’ is not at beginning of declaration [-Wold-style-declaration] 46 | const extern unsigned int riscv_kexec_relocate_size; | ^~~~~ arch/riscv/kernel/machine_kexec.c:125:6: warning: no previous prototype for ‘machine_shutdown’ [-Wmissing-prototypes] 125 | void machine_shutdown(void) | ^~~~~~~~~~~~~~~~ arch/riscv/kernel/machine_kexec.c:147:1: warning: no previous prototype for ‘machine_crash_shutdown’ [-Wmissing-prototypes] 147 | machine_crash_shutdown(struct pt_regs *regs) | ^~~~~~~~~~~~~~~~~~~~~~ arch/riscv/kernel/machine_kexec.c:23: warning: Function parameter or member 'image' not described in 'kexec_image_info' arch/riscv/kernel/machine_kexec.c:53: warning: Function parameter or member 'image' not described in 'machine_kexec_prepare' arch/riscv/kernel/machine_kexec.c:114: warning: Function parameter or member 'image' not described in 'machine_kexec_cleanup' arch/riscv/kernel/machine_kexec.c:148: warning: Function parameter or member 'regs' not described in 'machine_crash_shutdown' arch/riscv/kernel/machine_kexec.c:167: warning: Function parameter or member 'image' not described in 'machine_kexec' Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-22riscv: kprobes: Fix build error when MMU=nJisheng Zhang1-0/+2
lkp reported a randconfig failure: arch/riscv/kernel/probes/kprobes.c:90:22: error: use of undeclared identifier 'PAGE_KERNEL_READ_EXEC' We implemented the alloc_insn_page() to allocate PAGE_KERNEL_READ_EXEC page for kprobes insn page for STRICT_MODULE_RWX. But if MMU=n, we should fall back to the generic weak alloc_insn_page() by generic kprobe subsystem. Fixes: cdd1b2bd358f ("riscv: kprobes: Implement alloc_insn_page()") Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-22riscv: stacktrace: fix the riscv stacktrace when CONFIG_FRAME_POINTER enabledChen Huang1-7/+7
As [1] and [2] said, the arch_stack_walk should not to trace itself, or it will leave the trace unexpectedly when called. The example is when we do "cat /sys/kernel/debug/page_owner", all pages' stack is the same. arch_stack_walk+0x18/0x20 stack_trace_save+0x40/0x60 register_dummy_stack+0x24/0x5e init_page_owner+0x2e So we use __builtin_frame_address(1) as the first frame to be walked. And mark the arch_stack_walk() noinline. We found that pr_cont will affact pages' stack whose task state is RUNNING when testing "echo t > /proc/sysrq-trigger". So move the place of pr_cont and mark the function dump_backtrace() noinline. Also we move the case when task == NULL into else branch, and test for it in "echo c > /proc/sysrq-trigger". [1] https://lore.kernel.org/lkml/20210319184106.5688-1-mark.rutland@arm.com/ [2] https://lore.kernel.org/lkml/20210317142050.57712-1-chenjun102@huawei.com/ Signed-off-by: Chen Huang <chenhuang5@huawei.com> Fixes: 5d8544e2d007 ("RISC-V: Generic library routines and assembly") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-06riscv: remove unused handle_exception symbolRouven Czerwinski1-2/+0
Since commit 79b1feba5455 ("RISC-V: Setup exception vector early") exception vectors are setup early and the handle_exception symbol from the asm files is no longer referenced in traps.c. Remove it. Signed-off-by: Rouven Czerwinski <rouven@czerwinskis.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-06riscv: Consistify protect_kernel_linear_mapping_text_rodata() useGeert Uytterhoeven1-2/+0
The various uses of protect_kernel_linear_mapping_text_rodata() are not consistent: - Its definition depends on "64BIT && !XIP_KERNEL", - Its forward declaration depends on MMU, - Its single caller depends on "STRICT_KERNEL_RWX && 64BIT && MMU && !XIP_KERNEL". Fix this by settling on the dependencies of the caller, which can be simplified as STRICT_KERNEL_RWX depends on "MMU && !XIP_KERNEL". Provide a dummy definition, as the caller is protected by "IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)" instead of "#ifdef CONFIG_STRICT_KERNEL_RWX". Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Alexandre Ghiti <alex@ghiti.fr> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-06Merge tag 'riscv-for-linus-5.13-mw0' of ↵Linus Torvalds22-92/+884
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the memtest= kernel command-line argument. - Support for building the kernel with FORTIFY_SOURCE. - Support for generic clockevent broadcasts. - Support for the buildtar build target. - Some build system cleanups to pass more LLVM-friendly arguments. - Support for kprobes. - A rearranged kernel memory map, the first part of supporting sv48 systems. - Improvements to kexec, along with support for kdump and crash kernels. - An alternatives-based errata framework, along with support for handling a pair of errata that manifest on some SiFive designs (including the HiFive Unmatched). - Support for XIP. - A device tree for the Microchip PolarFire ICICLE SoC and associated dev board. ... along with a bunch of cleanups. There are already a handful of fixes on the list so there will likely be a part 2. * tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (45 commits) RISC-V: Always define XIP_FIXUP riscv: Remove 32b kernel mapping from page table dump riscv: Fix 32b kernel build with CONFIG_DEBUG_VIRTUAL=y RISC-V: Fix error code returned by riscv_hartid_to_cpuid() RISC-V: Enable Microchip PolarFire ICICLE SoC RISC-V: Initial DTS for Microchip ICICLE board dt-bindings: riscv: microchip: Add YAML documentation for the PolarFire SoC RISC-V: Add Microchip PolarFire SoC kconfig option RISC-V: enable XIP RISC-V: Add crash kernel support RISC-V: Add kdump support RISC-V: Improve init_resources() RISC-V: Add kexec support RISC-V: Add EM_RISCV to kexec UAPI header riscv: vdso: fix and clean-up Makefile riscv/mm: Use BUG_ON instead of if condition followed by BUG. riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe riscv: Set ARCH_HAS_STRICT_MODULE_RWX if MMU riscv: module: Create module allocations without exec permissions riscv: bpf: Avoid breaking W^X ...
2021-05-01RISC-V: Fix error code returned by riscv_hartid_to_cpuid()Anup Patel1-1/+1
We should return a negative error code upon failure in riscv_hartid_to_cpuid() instead of NR_CPUS. This is also aligned with all uses of riscv_hartid_to_cpuid() which expect negative error code upon failure. Fixes: 6825c7a80f18 ("RISC-V: Add logical CPU indexing for RISC-V") Fixes: f99fb607fb2b ("RISC-V: Use Linux logical CPU number instead of hartid") Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26RISC-V: enable XIPVitaly Wool5-4/+195
Introduce XIP (eXecute In Place) support for RISC-V platforms. It allows code to be executed directly from non-volatile storage directly addressable by the CPU, such as QSPI NOR flash which can be found on many RISC-V platforms. This makes way for significant optimization of RAM footprint. The XIP kernel is not compressed since it has to run directly from flash, so it will occupy more space on the non-volatile storage. The physical flash address used to link the kernel object files and for storing it has to be known at compile time and is represented by a Kconfig option. XIP on RISC-V will for the time being only work on MMU-enabled kernels. Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com> [Alex: Rebase on top of "Move kernel mapping outside the linear mapping" ] Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> [Palmer: disable XIP for allyesconfig] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26RISC-V: Add crash kernel supportNick Kossifidis3-0/+59
This patch allows Linux to act as a crash kernel for use with kdump. Userspace will let the crash kernel know about the memory region it can use through linux,usable-memory property on the /memory node (overriding its reg property), and about the memory region where the elf core header of the previous kernel is saved, through a reserved-memory node with a compatible string of "linux,elfcorehdr". This approach is the least invasive and re-uses functionality already present. I tested this on riscv64 qemu and it works as expected, you may test it by retrieving the dmesg of the previous kernel through /proc/vmcore, using the vmcore-dmesg utility from kexec-tools. Signed-off-by: Nick Kossifidis <mick@ics.forth.gr> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26RISC-V: Add kdump supportNick Kossifidis5-21/+159
This patch adds support for kdump, the kernel will reserve a region for the crash kernel and jump there on panic. In order for userspace tools (kexec-tools) to prepare the crash kernel kexec image, we also need to expose some information on /proc/iomem for the memory regions used by the kernel and for the region reserved for crash kernel. Note that on userspace the device tree is used to determine the system's memory layout so the "System RAM" on /proc/iomem is ignored. I tested this on riscv64 qemu and works as expected, you may test it by triggering a crash through /proc/sysrq_trigger: echo c > /proc/sysrq_trigger Signed-off-by: Nick Kossifidis <mick@ics.forth.gr> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26RISC-V: Improve init_resources()Nick Kossifidis1-44/+46
The kernel region is always present and we know where it is, no need to look for it inside the loop, just ignore it like the rest of the reserved regions within system's memory. Additionally, we don't need to call memblock_free inside the loop, as if called it'll split the region of pre-allocated resources in two parts, messing things up, just re-use the previous pre-allocated resource and free any unused resources after both loops finish. Signed-off-by: Nick Kossifidis <mick@ics.forth.gr> [Palmer: commit text] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26RISC-V: Add kexec supportNick Kossifidis3-0/+348
This patch adds support for kexec on RISC-V. On SMP systems it depends on HOTPLUG_CPU in order to be able to bring up all harts after kexec. It also needs a recent OpenSBI version that supports the HSM extension. I tested it on riscv64 QEMU on both an smp and a non-smp system. Signed-off-by: Nick Kossifidis <mick@ics.forth.gr> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: vdso: fix and clean-up MakefileJisheng Zhang1-2/+2
Running "make" on an already compiled kernel tree will rebuild the kernel even without any modifications: CALL linux/scripts/checksyscalls.sh CALL linux/scripts/atomic/check-atomics.sh CHK include/generated/compile.h SO2S arch/riscv/kernel/vdso/vdso-syms.S AS arch/riscv/kernel/vdso/vdso-syms.o AR arch/riscv/kernel/vdso/built-in.a AR arch/riscv/kernel/built-in.a AR arch/riscv/built-in.a GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o AR init/built-in.a LD vmlinux.o The reason is "Any target that utilizes if_changed must be listed in $(targets), otherwise the command line check will fail, and the target will always be built" as explained by Documentation/kbuild/makefiles.rst Fix this build bug by adding vdso-syms.S to $(targets) At the same time, there are two trivial clean up modifications: - the vdso-dummy.o is not needed any more after so remove it. - vdso.lds is a generated file, so it should be prefixed with $(obj)/ instead of $(src)/ Fixes: c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+") Cc: stable@vger.kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobeLiao Chang1-1/+3
The execution of sys_read end up hitting a BUG_ON() in __find_get_block after installing kprobe at sys_read, the BUG message like the following: [ 65.708663] ------------[ cut here ]------------ [ 65.709987] kernel BUG at fs/buffer.c:1251! [ 65.711283] Kernel BUG [#1] [ 65.712032] Modules linked in: [ 65.712925] CPU: 0 PID: 51 Comm: sh Not tainted 5.12.0-rc4 #1 [ 65.714407] Hardware name: riscv-virtio,qemu (DT) [ 65.715696] epc : __find_get_block+0x218/0x2c8 [ 65.716835] ra : __getblk_gfp+0x1c/0x4a [ 65.717831] epc : ffffffe00019f11e ra : ffffffe00019f56a sp : ffffffe002437930 [ 65.719553] gp : ffffffe000f06030 tp : ffffffe0015abc00 t0 : ffffffe00191e038 [ 65.721290] t1 : ffffffe00191e038 t2 : 000000000000000a s0 : ffffffe002437960 [ 65.723051] s1 : ffffffe00160ad00 a0 : ffffffe00160ad00 a1 : 000000000000012a [ 65.724772] a2 : 0000000000000400 a3 : 0000000000000008 a4 : 0000000000000040 [ 65.726545] a5 : 0000000000000000 a6 : ffffffe00191e000 a7 : 0000000000000000 [ 65.728308] s2 : 000000000000012a s3 : 0000000000000400 s4 : 0000000000000008 [ 65.730049] s5 : 000000000000006c s6 : ffffffe00240f800 s7 : ffffffe000f080a8 [ 65.731802] s8 : 0000000000000001 s9 : 000000000000012a s10: 0000000000000008 [ 65.733516] s11: 0000000000000008 t3 : 00000000000003ff t4 : 000000000000000f [ 65.734434] t5 : 00000000000003ff t6 : 0000000000040000 [ 65.734613] status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003 [ 65.734901] Call Trace: [ 65.735076] [<ffffffe00019f11e>] __find_get_block+0x218/0x2c8 [ 65.735417] [<ffffffe00020017a>] __ext4_get_inode_loc+0xb2/0x2f6 [ 65.735618] [<ffffffe000201b6c>] ext4_get_inode_loc+0x3a/0x8a [ 65.735802] [<ffffffe000203380>] ext4_reserve_inode_write+0x2e/0x8c [ 65.735999] [<ffffffe00020357a>] __ext4_mark_inode_dirty+0x4c/0x18e [ 65.736208] [<ffffffe000206bb0>] ext4_dirty_inode+0x46/0x66 [ 65.736387] [<ffffffe000192914>] __mark_inode_dirty+0x12c/0x3da [ 65.736576] [<ffffffe000180dd2>] touch_atime+0x146/0x150 [ 65.736748] [<ffffffe00010d762>] filemap_read+0x234/0x246 [ 65.736920] [<ffffffe00010d834>] generic_file_read_iter+0xc0/0x114 [ 65.737114] [<ffffffe0001f5d7a>] ext4_file_read_iter+0x42/0xea [ 65.737310] [<ffffffe000163f2c>] new_sync_read+0xe2/0x15a [ 65.737483] [<ffffffe000165814>] vfs_read+0xca/0xf2 [ 65.737641] [<ffffffe000165bae>] ksys_read+0x5e/0xc8 [ 65.737816] [<ffffffe000165c26>] sys_read+0xe/0x16 [ 65.737973] [<ffffffe000003972>] ret_from_syscall+0x0/0x2 [ 65.738858] ---[ end trace fe93f985456c935d ]--- A simple reproducer looks like: echo 'p:myprobe sys_read fd=%a0 buf=%a1 count=%a2' > /sys/kernel/debug/tracing/kprobe_events echo 1 > /sys/kernel/debug/tracing/events/kprobes/myprobe/enable cat /sys/kernel/debug/tracing/trace Here's what happens to hit that BUG_ON(): 1) After installing kprobe at entry of sys_read, the first instruction is replaced by 'ebreak' instruction on riscv64 platform. 2) Once kernel reach the 'ebreak' instruction at the entry of sys_read, it trap into the riscv breakpoint handler, where it do something to setup for coming single-step of origin instruction, including backup the 'sstatus' in pt_regs, followed by disable interrupt during single stepping via clear 'SIE' bit of 'sstatus' in pt_regs. 3) Then kernel restore to the instruction slot contains two instructions, one is original instruction at entry of sys_read, the other is 'ebreak'. Here it trigger a 'Instruction page fault' exception (value at 'scause' is '0xc'), if PF is not filled into PageTabe for that slot yet. 4) Again kernel trap into page fault exception handler, where it choose different policy according to the state of running kprobe. Because afte 2) the state is KPROBE_HIT_SS, so kernel reset the current kprobe and 'pc' points back to the probe address. 5) Because 'epc' point back to 'ebreak' instrution at sys_read probe, kernel trap into breakpoint handler again, and repeat the operations at 2), however 'sstatus' without 'SIE' is keep at 4), it cause the real 'sstatus' saved at 2) is overwritten by the one withou 'SIE'. 6) When kernel cross the probe the 'sstatus' CSR restore with value without 'SIE', and reach __find_get_block where it requires the interrupt must be enabled. Fix this is very trivial, just restore the value of 'sstatus' in pt_regs with backup one at 2) when the instruction being single stepped cause a page fault. Fixes: c22b0bcb1dd02 ("riscv: Add kprobes supported") Signed-off-by: Liao Chang <liaochang1@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: module: Create module allocations without exec permissionsJisheng Zhang1-1/+1
The core code manages the executable permissions of code regions of modules explicitly, it is not necessary to create the module vmalloc regions with RWX permissions. Create them with RW- permissions instead. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: kprobes: Implement alloc_insn_page()Jisheng Zhang1-0/+8
Allocate PAGE_KERNEL_READ_EXEC(read only, executable) page for kprobes insn page. This is to prepare for STRICT_MODULE_RWX. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Constify sbi_ipi_opsJisheng Zhang2-3/+3
Constify the sbi_ipi_ops so that it will be placed in the .rodata section. This will cause attempts to modify it to fail when strict page permissions are in place. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Constify sys_call_tableJisheng Zhang1-1/+1
Constify the sys_call_table so that it will be placed in the .rodata section. This will cause attempts to modify the table to fail when strict page permissions are in place. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Mark some global variables __ro_after_initJisheng Zhang4-9/+9
All of these are never modified after init, so they can be __ro_after_init. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: add __init section marker to some functionsJisheng Zhang1-1/+1
They are not needed after booting, so mark them as __init to move them to the __init section. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Move kernel mapping outside of linear mappingAlexandre Ghiti4-7/+12
This is a preparatory patch for relocatable kernel and sv48 support. The kernel used to be linked at PAGE_OFFSET address therefore we could use the linear mapping for the kernel mapping. But the relocated kernel base address will be different from PAGE_OFFSET and since in the linear mapping, two different virtual addresses cannot point to the same physical address, the kernel mapping needs to lie outside the linear mapping so that we don't have to copy it at the same physical offset. The kernel mapping is moved to the last 2GB of the address space, BPF is now always after the kernel and modules use the 2GB memory range right before the kernel, so BPF and modules regions do not overlap. KASLR implementation will simply have to move the kernel in the last 2GB range and just take care of leaving enough space for BPF. In addition, by moving the kernel to the end of the address space, both sv39 and sv48 kernels will be exactly the same without needing to be relocated at runtime. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> [Palmer: Squash the STRICT_RWX fix, and a !MMU fix] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Workaround mcount name prior to clang-13Nathan Chancellor1-5/+5
Prior to clang 13.0.0, the RISC-V name for the mcount symbol was "mcount", which differs from the GCC version of "_mcount", which results in the following errors: riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_level': main.c:(.text+0xe): undefined reference to `mcount' riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_start': main.c:(.text+0x4e): undefined reference to `mcount' riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_finish': main.c:(.text+0x92): undefined reference to `mcount' riscv64-linux-gnu-ld: init/main.o: in function `.LBB32_28': main.c:(.text+0x30c): undefined reference to `mcount' riscv64-linux-gnu-ld: init/main.o: in function `free_initmem': main.c:(.text+0x54c): undefined reference to `mcount' This has been corrected in https://reviews.llvm.org/D98881 but the minimum supported clang version is 10.0.1. To avoid build errors and to gain a working function tracer, adjust the name of the mcount symbol for older versions of clang in mount.S and recordmcount.pl. Link: https://github.com/ClangBuiltLinux/linux/issues/1331 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Use $(LD) instead of $(CC) to link vDSONathan Chancellor1-8/+4
Currently, the VDSO is being linked through $(CC). This does not match how the rest of the kernel links objects, which is through the $(LD) variable. When linking with clang, there are a couple of warnings about flags that will not be used during the link: clang-12: warning: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] clang-12: warning: argument unused during compilation: '-pg' [-Wunused-command-line-argument] '-no-pie' was added in commit 85602bea297f ("RISC-V: build vdso-dummy.o with -no-pie") to override '-pie' getting added to the ld command from distribution versions of GCC that enable PIE by default. It is technically no longer needed after commit c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+"), which removed vdso-dummy.o in favor of generating vdso-syms.S from vdso.so with $(NM) but this also resolves the issue in case it ever comes back due to having full control over the $(LD) command. '-pg' is for function tracing, it is not used during linking as clang states. These flags could be removed/filtered to fix the warnings but it is easier to just match the rest of the kernel and use $(LD) directly for linking. See commits fe00e50b2db8 ("ARM: 8858/1: vdso: use $(LD) instead of $(CC) to link VDSO") 691efbedc60d ("arm64: vdso: use $(LD) instead of $(CC) to link VDSO") 2ff906994b6c ("MIPS: VDSO: Use $(LD) instead of $(CC) to link VDSO") 2b2a25845d53 ("s390/vdso: Use $(LD) instead of $(CC) to link vDSO") for more information. The flags are converted to linker flags and '--eh-frame-hdr' is added to match what is added by GCC implicitly, which can be seen by adding '-v' to GCC's invocation. Additionally, since this area is being modified, use the $(OBJCOPY) variable instead of an open coded $(CROSS_COMPILE)objcopy so that the user's choice of objcopy binary is respected. Link: https://github.com/ClangBuiltLinux/linux/issues/803 Link: https://github.com/ClangBuiltLinux/linux/issues/970 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Fangrui Song <maskray@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: sifive: Apply errata "cip-453" patchVincent Chen1-2/+4
Add sign extension to the $badaddr before addressing the instruction page fault and instruction access fault to workaround the issue "cip-453". To avoid affecting the existing code sequence, this patch will creates two trampolines to add sign extension to the $badaddr. By the "alternative" mechanism, these two trampolines will replace the original exception handler of instruction page fault and instruction access fault in the excp_vect_table. In this case, only the specific SiFive CPU core jumps to the do_page_fault and do_trap_insn_fault through these two trampolines. Other CPUs are not affected. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Introduce alternative mechanism to apply errata solutionVincent Chen2-0/+11
Introduce the "alternative" mechanism from ARM64 and x86 to apply the CPU vendors' errata solution at runtime. The main purpose of this patch is to provide a framework. Therefore, the implementation is quite basic for now so that some scenarios could not use this schemei, such as patching code to a module, relocating the patching code and heterogeneous CPU topology. Users could use the macro ALTERNATIVE to apply an errata to the existing code flow. In the macro ALTERNATIVE, users need to specify the manufacturer information(vendorid, archid, and impid) for this errata. Therefore, kernel will know this errata is suitable for which CPU core. During the booting procedure, kernel will select the errata required by the CPU core and then patch it. It means that the kernel only applies the errata to the specified CPU core. In this case, the vendor's errata does not affect each other at runtime. The above patching procedure only occurs during the booting phase, so we only take the overhead of the "alternative" mechanism once. This "alternative" mechanism is enabled by default to ensure that all required errata will be applied. However, users can disable this feature by the Kconfig "CONFIG_RISCV_ERRATA_ALTERNATIVE". Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Add 3 SBI wrapper functions to get cpu manufacturer informationVincent Chen1-0/+15
Add 3 wrapper functions to get vendor id, architecture id and implement id from M-mode Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-15riscv: keep interrupts disabled for BREAKPOINT exceptionJisheng Zhang1-0/+3
Current riscv's kprobe handlers are run with both preemption and interrupt enabled, this violates kprobe requirements. Fix this issue by keeping interrupts disabled for BREAKPOINT exception. Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") Cc: stable@vger.kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> [Palmer: add a comment] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-15riscv: kprobes/ftrace: Add recursion protection to the ftrace callbackJisheng Zhang1-1/+10
Currently, the riscv's kprobes(powerred by ftrace) handler is preemptible. Futher check indicates we miss something similar as the commit c536aa1c5b17 ("kprobes/ftrace: Add recursion protection to the ftrace callback"), so do similar modifications as the commit does. Fixes: 829adda597fe ("riscv: Add KPROBES_ON_FTRACE supported") Cc: stable@vger.kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-15riscv: add do_page_fault and do_trap_break into the kprobes blacklistJisheng Zhang1-0/+1
These two functions are used to implement the kprobes feature so they can't be kprobed. Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") Cc: stable@vger.kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-01riscv,entry: fix misaligned base for excp_vect_tableZihao Yu1-0/+1
In RV64, the size of each entry in excp_vect_table is 8 bytes. If the base of the table is not 8-byte aligned, loading an entry in the table will raise a misaligned exception. Although such exception will be handled by opensbi/bbl, this still causes performance degradation. Signed-off-by: Zihao Yu <yuzihao@ict.ac.cn> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-01riscv: Drop const annotation for spKefeng Wang1-1/+1
The const annotation should not be used for 'sp', or it will become read only and lead to bad stack output. Fixes: dec822771b01 ("riscv: stacktrace: Move register keyword to beginning of declaration") Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-29RISC-V: Don't print SBI version for all detected extensionsAnup Patel1-3/+3
The sbi_init() already prints SBI version before detecting various SBI extensions so we don't need to print SBI version for all detected SBI extensions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-16RISC-V: Fix out-of-bounds accesses in init_resources()Geert Uytterhoeven1-1/+2
init_resources() allocates an array of resources, based on the current total number of memory regions and reserved memory regions. However, allocating this array using memblock_alloc() might increase the number of reserved memory regions. If that happens, populating the array later based on the new number of regions will cause out-of-bounds writes beyond the end of the allocated array. Fix this by allocating one more entry, which may or may not be used. Fixes: 797f0375dd2ef5cd ("RISC-V: Do not allocate memblock while iterating reserved memblocks") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Atish Patra <atish.patra@wdc.com> Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-16ftrace: Fix spelling mistake "disabed" -> "disabled"Colin Ian King1-1/+1
There is a spelling mistake in a comment, fix it. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-16riscv: Enable generic clockevent broadcastGuo Ren1-0/+16
When percpu-timers are stopped by deep power saving mode, we need system timer help to broadcast IPI_TIMER. This is first introduced by broken x86 hardware, where the local apic timer stops in C3 state. But many other architectures(powerpc, mips, arm, hexagon, openrisc, sh) have supported the infrastructure to deal with Power Management issues. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-16riscv: fix bugon.cocci warningskernel test robot1-2/+1
Use BUG_ON instead of a if condition followed by BUG. Generated by: scripts/coccinelle/misc/bugon.cocci Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") CC: Guo Ren <guoren@linux.alibaba.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: kernel test robot <lkp@intel.com> Signed-off-by: Julia Lawall <julia.lawall@inria.fr> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-09riscv: ftrace: Use ftrace_get_regs helperNanyong Sun1-7/+9
Use ftrace_get_regs() helper call to get pt_regs from ftrace_regs struct, this makes the code simpler. Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-09riscv: process: Fix no prototype for show_regsNanyong Sun1-0/+1
Include header file to fix the following W=1 compilation warning: arch/riscv/kernel/process.c:78:6: warning: no previous prototype for ‘show_regs’ [-Wmissing-prototypes] 78 | void show_regs(struct pt_regs *regs) | ^~~~~~~~~ Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-09riscv: syscall_table: Reduce W=1 compilation warnings noiseNanyong Sun1-0/+1
Building riscv syscall table with W=1 throws the warning as following pattern: arch/riscv/kernel/syscall_table.c:14:36: warning: initialized field overwritten [-Woverride-init] 14 | #define __SYSCALL(nr, call) [nr] = (call), | ^ ./include/uapi/asm-generic/unistd.h:29:37: note: in expansion of macro ‘__SYSCALL’ 29 | #define __SC_COMP(_nr, _sys, _comp) __SYSCALL(_nr, _sys) | ^~~~~~~~~ ./include/uapi/asm-generic/unistd.h:34:1: note: in expansion of macro ‘__SC_COMP’ 34 | __SC_COMP(__NR_io_setup, sys_io_setup, compat_sys_io_setup) | ^~~~~~~~~ arch/riscv/kernel/syscall_table.c:14:36: note: (near initialization for ‘sys_call_table[0]’) 14 | #define __SYSCALL(nr, call) [nr] = (call), | ^ ./include/uapi/asm-generic/unistd.h:29:37: note: in expansion of macro ‘__SYSCALL’ 29 | #define __SC_COMP(_nr, _sys, _comp) __SYSCALL(_nr, _sys) | ^~~~~~~~~ ./include/uapi/asm-generic/unistd.h:34:1: note: in expansion of macro ‘__SC_COMP’ 34 | __SC_COMP(__NR_io_setup, sys_io_setup, compat_sys_io_setup) | ^~~~~~~~~ arch/riscv/kernel/syscall_table.c:14:36: warning: initialized field overwritten [-Woverride-init] ... Since we intentionally build the syscall tables this way,ignore the warning. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-09riscv: time: Fix no prototype for time_initNanyong Sun1-0/+1
Fix the following W=1 compilation warning: arch/riscv/kernel/time.c:16:13: warning: no previous prototype for ‘time_init’ [-Wmissing-prototypes] 16 | void __init time_init(void) | ^~~~~~~~~ Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-09riscv: sbi: Fix comment of __sbi_set_timer_v01Nanyong Sun1-1/+1
Fix the comment of __sbi_set_timer_v01, the function name in comment is missing '__' Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-03-09riscv: traps: Fix no prototype warningsNanyong Sun1-0/+1
Fix all W=1 compilation warnings:'no previous prototype for' in arch/riscv/kernel/traps.c: arch/riscv/kernel/traps.c:96:15: warning: no previous prototype for ‘do_trap_unknown’ [-Wmissing-prototypes] 96 | DO_ERROR_INFO(do_trap_unknown, | ^~~~~~~~~~~~~~~ arch/riscv/kernel/traps.c:91:27: note: in definition of macro ‘DO_ERROR_INFO’ 91 | asmlinkage __visible void name(struct pt_regs *regs) \ | ^~~~ arch/riscv/kernel/traps.c:98:15: warning: no previous prototype for ‘do_trap_insn_misaligned’ [-Wmissing-prototypes] 98 | DO_ERROR_INFO(do_trap_insn_misaligned, | ^~~~~~~~~~~~~~~~~~~~~~~ arch/riscv/kernel/traps.c:91:27: note: in definition of macro ‘DO_ERROR_INFO’ 91 | asmlinkage __visible void name(struct pt_regs *regs) \ | ^~~~ arch/riscv/kernel/traps.c:100:15: warning: no previous prototype for ‘do_trap_insn_fault’ [-Wmissing-prototypes] ... Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> [Palmer: fix checkpatch warnings] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-27Merge tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull io_uring thread rewrite from Jens Axboe: "This converts the io-wq workers to be forked off the tasks in question instead of being kernel threads that assume various bits of the original task identity. This kills > 400 lines of code from io_uring/io-wq, and it's the worst part of the code. We've had several bugs in this area, and the worry is always that we could be missing some pieces for file types doing unusual things (recent /dev/tty example comes to mind, userfaultfd reads installing file descriptors is another fun one... - both of which need special handling, and I bet it's not the last weird oddity we'll find). With these identical workers, we can have full confidence that we're never missing anything. That, in itself, is a huge win. Outside of that, it's also more efficient since we're not wasting space and code on tracking state, or switching between different states. I'm sure we're going to find little things to patch up after this series, but testing has been pretty thorough, from the usual regression suite to production. Any issue that may crop up should be manageable. There's also a nice series of further reductions we can do on top of this, but I wanted to get the meat of it out sooner rather than later. The general worry here isn't that it's fundamentally broken. Most of the little issues we've found over the last week have been related to just changes in how thread startup/exit is done, since that's the main difference between using kthreads and these kinds of threads. In fact, if all goes according to plan, I want to get this into the 5.10 and 5.11 stable branches as well. That said, the changes outside of io_uring/io-wq are: - arch setup, simple one-liner to each arch copy_thread() implementation. - Removal of net and proc restrictions for io_uring, they are no longer needed or useful" * tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits) io-wq: remove now unused IO_WQ_BIT_ERROR io_uring: fix SQPOLL thread handling over exec io-wq: improve manager/worker handling over exec io_uring: ensure SQPOLL startup is triggered before error shutdown io-wq: make buffered file write hashed work map per-ctx io-wq: fix race around io_worker grabbing io-wq: fix races around manager/worker creation and task exit io_uring: ensure io-wq context is always destroyed for tasks arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread() io_uring: cleanup ->user usage io-wq: remove nr_process accounting io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS net: remove cmsg restriction from io_uring based send/recvmsg calls Revert "proc: don't allow async path resolution of /proc/self components" Revert "proc: don't allow async path resolution of /proc/thread-self components" io_uring: move SQPOLL thread io-wq forked worker io-wq: make io_wq_fork_thread() available to other users io-wq: only remove worker from free_list, if it was there io_uring: remove io_identity io_uring: remove any grabbing of context ...
2021-02-26Merge tag 'riscv-for-linus-5.12-mw0' of ↵Linus Torvalds26-302/+1357
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "A handful of new RISC-V related patches for this merge window: - A check to ensure drivers are properly using uaccess. This isn't manifesting with any of the drivers I'm currently using, but may catch errors in new drivers. - Some preliminary support for the FU740, along with the HiFive Unleashed it will appear on. - NUMA support for RISC-V, which involves making the arm64 code generic. - Support for kasan on the vmalloc region. - A handful of new drivers for the Kendryte K210, along with the DT plumbing required to boot on a handful of K210-based boards. - Support for allocating ASIDs. - Preliminary support for kernels larger than 128MiB. - Various other improvements to our KASAN support, including the utilization of huge pages when allocating the KASAN regions. We may have already found a bug with the KASAN_VMALLOC code, but it's passing my tests. There's a fix in the works, but that will probably miss the merge window. * tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (75 commits) riscv: Improve kasan population by using hugepages when possible riscv: Improve kasan population function riscv: Use KASAN_SHADOW_INIT define for kasan memory initialization riscv: Improve kasan definitions riscv: Get rid of MAX_EARLY_MAPPING_SIZE soc: canaan: Sort the Makefile alphabetically riscv: Disable KSAN_SANITIZE for vDSO riscv: Remove unnecessary declaration riscv: Add Canaan Kendryte K210 SD card defconfig riscv: Update Canaan Kendryte K210 defconfig riscv: Add Kendryte KD233 board device tree riscv: Add SiPeed MAIXDUINO board device tree riscv: Add SiPeed MAIX GO board device tree riscv: Add SiPeed MAIX DOCK board device tree riscv: Add SiPeed MAIX BiT board device tree riscv: Update Canaan Kendryte K210 device tree dt-bindings: add resets property to dw-apb-timer dt-bindings: fix sifive gpio properties dt-bindings: update sifive uart compatible string dt-bindings: update sifive clint compatible string ...
2021-02-22riscv: Disable KSAN_SANITIZE for vDSOTobias Klauser1-1/+2
We use the generic C VDSO implementations of a handful of clock-related functions. When kasan is enabled this results in asan stub calls that are unlikely to be resolved by userspace, this just disables KASAN when building the VDSO. Verified the fix on a kernel with KASAN enabled using vDSO selftests. Link: https://lore.kernel.org/lkml/CACT4Y+ZNJBnkKHXUf=tm_yuowvZvHwN=0rmJ=7J+xFd+9r_6pQ@mail.gmail.com/ Tested-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Tested-by: Dmitry Vyukov <dvyukov@google.com> [Palmer: commit text] 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>
2021-02-22RISC-V: Add a non-void return for sbi v02 functionsAtish Patra1-16/+16
SBI v0.2 functions can return an error code from SBI implementation. We are already processing the SBI error code and coverts it to the Linux error code. Propagate to the error code to the caller as well. As of now, kvm is the only user of these error codes. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-21arch: setup PF_IO_WORKER threads like PF_KTHREADJens Axboe1-1/+1
PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the sense that we don't assign ->set_child_tid with our own structure. Just ensure that every arch sets up the PF_IO_WORKER threads like kthreads in the arch implementation of copy_thread(). Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-18RISC-V: probes: Treat the instruction stream as host-endianPalmer Dabbelt2-2/+2
Neither of these are actually correct: the instruction stream is defined (for versions of the ISA manual newer than 2.2) as a stream of 16-bit little-endian parcels, which is different than just being little-endian. In theory we should represent this as a type, but we don't have any concrete plans for the big endian stuff so it doesn't seem worth the time -- we've got variants of this all over the place. Instead I'm just dropping the unnecessary type conversion, which is a NOP on LE systems but causes an sparse error as the types are all mixed up. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com> Acked-by: Guo Ren <guoren@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 06:21:12 +0000