linux-dev/arch/riscv/mm/Makefile, branch master

riscv: Add support for non-coherent devices using zicbom extension

2022-07-28T22:30:51Z

The Zicbom ISA-extension was ratified in november 2021 and introduces instructions for dcache invalidate, clean and flush operations. Implement cache management operations for non-coherent devices based on them. Of course not all cores will support this, so implement an alternative-based mechanism that replaces empty instructions with ones done around Zicbom instructions. As discussed in previous versions, assume the platform being coherent by default so that non-coherent devices need to get marked accordingly by firmware. Reviewed-by: Christoph Hellwig Signed-off-by: Heiko Stuebner Reviewed-by: Guo Ren Link: https://lore.kernel.org/r/20220706231536.2041855-4-heiko@sntech.de Signed-off-by: Palmer Dabbelt

riscv: Fix config KASAN && DEBUG_VIRTUAL

2022-03-03T23:32:41Z

__virt_to_phys function is called very early in the boot process (ie kasan_early_init) so it should not be instrumented by KASAN otherwise it bugs. Fix this by declaring phys_addr.c as non-kasan instrumentable. Signed-off-by: Alexandre Ghiti Fixes: 8ad8b72721d0 (riscv: Add KASAN support) Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt

riscv: Fixup patch_text panic in ftrace

2021-01-14T23:09:04Z

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=, conv=, ppos=, lenp=, buffer=, write=, table=) at kernel/sysctl.c:964 2 proc_dointvec_minmax (ppos=, lenp=, buffer=, write=, table=) at kernel/sysctl.c:964 3 proc_do_static_key (table=, write=1, buffer=0x0, lenp=0x0, ppos=0x7bf897061f9a0800) at kernel/sysctl.c:1643 4 0xffffffe000206792 in ftrace_make_call (rec=, addr=) 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=) 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=) 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=) 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 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 0xffffffe000204724 <+16>: beqz a0,0xffffffe00020472e 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 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 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 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 Reviewed-by: Atish Patra Signed-off-by: Palmer Dabbelt

riscv: Fixup wrong ftrace remove cflag

2021-01-14T23:09:03Z

We must use $(CC_FLAGS_FTRACE) instead of directly using -pg. It will cause -fpatchable-function-entry error. Signed-off-by: Guo Ren Signed-off-by: Palmer Dabbelt

riscv: Allow building with kcov coverage

2020-07-30T18:37:35Z

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 Acked-by: Dmitry Vyukov Signed-off-by: Palmer Dabbelt

riscv: Add support to dump the kernel page tables

2020-03-26T16:29:49Z

In a similar manner to arm64, x86, powerpc, etc., it can traverse all page tables, and dump the page table layout with the memory types and permissions. Add a debugfs file at /sys/kernel/debug/kernel_page_tables to export the page table layout to userspace. Signed-off-by: Zong Li Tested-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt

riscv: add ARCH_HAS_SET_MEMORY support

2020-03-26T16:24:30Z

Add set_memory_ro/rw/x/nx architecture hooks to change the page attribution. Use own set_memory.h rather than generic set_memory.h (i.e. include/asm-generic/set_memory.h), because we want to add other function prototypes here. Signed-off-by: Zong Li Signed-off-by: Palmer Dabbelt

riscv: mm: add support for CONFIG_DEBUG_VIRTUAL

2020-01-23T18:40:06Z

This patch implements CONFIG_DEBUG_VIRTUAL to do additional checks on virt_to_phys and __pa_symbol calls. virt_to_phys used for linear mapping check, and __pa_symbol used for kernel symbol check. In current RISC-V, kernel image maps to linear mapping area. If CONFIG_DEBUG_VIRTUAL is disable, these two functions calculate the offset on the address feded directly without any checks. The result of test_debug_virtual as follows: [ 0.358456] ------------[ cut here ]------------ [ 0.358738] virt_to_phys used for non-linear address: (____ptrval____) (0xffffffd000000000) [ 0.359174] WARNING: CPU: 0 PID: 1 at arch/riscv/mm/physaddr.c:16 __virt_to_phys+0x3c/0x50 [ 0.359409] Modules linked in: [ 0.359630] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0-rc3-00002-g5133c5c0ca13 #57 [ 0.359861] epc: ffffffe000253d1a ra : ffffffe000253d1a sp : ffffffe03aa87da0 [ 0.360019] gp : ffffffe000ae03b0 tp : ffffffe03aa88000 t0 : ffffffe000af2660 [ 0.360175] t1 : 0000000000000064 t2 : 00000000000000b7 s0 : ffffffe03aa87dc0 [ 0.360330] s1 : ffffffd000000000 a0 : 000000000000004f a1 : 0000000000000000 [ 0.360492] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffe000a84358 [ 0.360672] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000000000 [ 0.360876] s2 : ffffffe000ae0600 s3 : ffffffe00000fc7c s4 : ffffffe0000224b0 [ 0.361067] s5 : ffffffe000030890 s6 : ffffffe000022470 s7 : 0000000000000008 [ 0.361267] s8 : ffffffe0000002c4 s9 : ffffffe000ae0640 s10: ffffffe000ae0630 [ 0.361453] s11: 0000000000000000 t3 : 0000000000000000 t4 : 000000000001e6d0 [ 0.361636] t5 : ffffffe000ae0a18 t6 : ffffffe000aee54e [ 0.361806] status: 0000000000000120 badaddr: 0000000000000000 cause: 0000000000000003 [ 0.362056] ---[ end trace aec0bf78d4978122 ]--- [ 0.362404] PA: 0xfffffff080200000 for VA: 0xffffffd000000000 [ 0.362607] PA: 0x00000000baddd2d0 for VA: 0xffffffe03abdd2d0 Signed-off-by: Zong Li Reviewed-by: Paul Walmsley Tested-by: Paul Walmsley Signed-off-by: Palmer Dabbelt

riscv: Add KASAN support

2020-01-22T21:09:58Z

This patch ports the feature Kernel Address SANitizer (KASAN). Note: The start address of shadow memory is at the beginning of kernel space, which is 2^64 - (2^39 / 2) in SV39. The size of the kernel space is 2^38 bytes so the size of shadow memory should be 2^38 / 8. Thus, the shadow memory would not overlap with the fixmap area. There are currently two limitations in this port, 1. RV64 only: KASAN need large address space for extra shadow memory region. 2. KASAN can't debug the modules since the modules are allocated in VMALLOC area. We mapped the shadow memory, which corresponding to VMALLOC area, to the kasan_early_shadow_page because we don't have enough physical space for all the shadow memory corresponding to VMALLOC area. Signed-off-by: Nick Hu Reported-by: Greentime Hu Signed-off-by: Palmer Dabbelt

riscv: move sifive_l2_cache.c to drivers/soc

2019-12-20T11:40:24Z

The sifive_l2_cache.c is in no way related to RISC-V architecture memory management. It is a little stub driver working around the fact that the EDAC maintainers prefer their drivers to be structured in a certain way that doesn't fit the SiFive SOCs. Move the file to drivers/soc and add a Kconfig option for it, as well as the whole drivers/soc boilerplate for CONFIG_SOC_SIFIVE. Fixes: a967a289f169 ("RISC-V: sifive_l2_cache: Add L2 cache controller driver for SiFive SoCs") Signed-off-by: Christoph Hellwig Reviewed-by: Borislav Petkov [paul.walmsley@sifive.com: keep the MAINTAINERS change specific to the L2$ controller code] Signed-off-by: Paul Walmsley