From 6a00ef4493706a23120057fafbc62379bcde11ec Mon Sep 17 00:00:00 2001 From: Changbin Du Date: Mon, 17 Jan 2022 23:44:33 +0800 Subject: riscv: eliminate unreliable __builtin_frame_address(1) I tried different pieces of code which uses __builtin_frame_address(1) (with both gcc version 7.5.0 and 10.3.0) to verify whether it works as expected on riscv64. The result is negative. What the compiler had generated is as below: 31 fp = (unsigned long)__builtin_frame_address(1); 0xffffffff80006024 <+200>: ld s1,0(s0) It takes '0(s0)' as the address of frame 1 (caller), but the actual address should be '-16(s0)'. | ... | <-+ +-----------------+ | | return address | | | previous fp | | | saved registers | | | local variables | | $fp --> | ... | | +-----------------+ | | return address | | | previous fp --------+ | saved registers | $sp --> | local variables | +-----------------+ This leads the kernel can not dump the full stack trace on riscv. [ 7.222126][ T1] Call Trace: [ 7.222804][ T1] [] dump_backtrace+0x2c/0x3a This problem is not exposed on most riscv builds just because the '0(s0)' occasionally is the address frame 2 (caller's caller), if only ra and fp are stored in frame 1 (caller). | ... | <-+ +-----------------+ | | return address | | $fp --> | previous fp | | +-----------------+ | | return address | | | previous fp --------+ | saved registers | $sp --> | local variables | +-----------------+ This could be a *bug* of gcc that should be fixed. But as noted in gcc manual "Calling this function with a nonzero argument can have unpredictable effects, including crashing the calling program.", let's remove the '__builtin_frame_address(1)' in backtrace code. With this fix now it can show full stack trace: [ 10.444838][ T1] Call Trace: [ 10.446199][ T1] [] dump_backtrace+0x2c/0x3a [ 10.447711][ T1] [] show_stack+0x32/0x3e [ 10.448710][ T1] [] dump_stack_lvl+0x58/0x7a [ 10.449941][ T1] [] dump_stack+0x14/0x1c [ 10.450929][ T1] [] ubsan_epilogue+0x10/0x5a [ 10.451869][ T1] [] __ubsan_handle_load_invalid_value+0x6c/0x78 [ 10.453049][ T1] [] __pagevec_release+0x62/0x64 [ 10.455476][ T1] [] truncate_inode_pages_range+0x132/0x5be [ 10.456798][ T1] [] truncate_inode_pages+0x24/0x30 [ 10.457853][ T1] [] kill_bdev+0x32/0x3c ... Signed-off-by: Changbin Du Fixes: eac2f3059e02 ("riscv: stacktrace: fix the riscv stacktrace when CONFIG_FRAME_POINTER enabled") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/stacktrace.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c index 201ee206fb57..14d2b53ec322 100644 --- a/arch/riscv/kernel/stacktrace.c +++ b/arch/riscv/kernel/stacktrace.c @@ -22,15 +22,16 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs, bool (*fn)(void *, unsigned long), void *arg) { unsigned long fp, sp, pc; + int level = 0; if (regs) { fp = frame_pointer(regs); sp = user_stack_pointer(regs); pc = instruction_pointer(regs); } else if (task == NULL || task == current) { - fp = (unsigned long)__builtin_frame_address(1); - sp = (unsigned long)__builtin_frame_address(0); - pc = (unsigned long)__builtin_return_address(0); + fp = (unsigned long)__builtin_frame_address(0); + sp = sp_in_global; + pc = (unsigned long)walk_stackframe; } else { /* task blocked in __switch_to */ fp = task->thread.s[0]; @@ -42,7 +43,7 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs, unsigned long low, high; struct stackframe *frame; - if (unlikely(!__kernel_text_address(pc) || !fn(arg, pc))) + if (unlikely(!__kernel_text_address(pc) || (level++ >= 1 && !fn(arg, pc)))) break; /* Validate frame pointer */ -- cgit v1.2.3 From 3c04d84508b54fcf524093b0d4a718680ed67f0f Mon Sep 17 00:00:00 2001 From: Myrtle Shah Date: Thu, 20 Jan 2022 15:33:37 +0000 Subject: riscv: Fix XIP_FIXUP_FLASH_OFFSET There were several problems with the calculation. Not only was an 'and' being computed into t1 but thrown away; but the 'and' itself would cause problems if the granularity of the XIP physical address was less than XIP_OFFSET - in my case I had the kernel image at 2MB in SPI flash. Fixes: f9ace4ede49b ("riscv: remove .text section size limitation for XIP") Cc: stable@vger.kernel.org Signed-off-by: Myrtle Shah Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/head.S | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'arch') diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 2363b43312fc..ec07f991866a 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -22,14 +22,13 @@ add \reg, \reg, t0 .endm .macro XIP_FIXUP_FLASH_OFFSET reg - la t1, __data_loc - li t0, XIP_OFFSET_MASK - and t1, t1, t0 - li t1, XIP_OFFSET - sub t0, t0, t1 - sub \reg, \reg, t0 + la t0, __data_loc + REG_L t1, _xip_phys_offset + sub \reg, \reg, t1 + add \reg, \reg, t0 .endm _xip_fixup: .dword CONFIG_PHYS_RAM_BASE - CONFIG_XIP_PHYS_ADDR - XIP_OFFSET +_xip_phys_offset: .dword CONFIG_XIP_PHYS_ADDR + XIP_OFFSET #else .macro XIP_FIXUP_OFFSET reg .endm -- cgit v1.2.3 From 4b1c70aa8ed8249608bb991380cb8ff423edf49e Mon Sep 17 00:00:00 2001 From: Palmer Dabbelt Date: Fri, 4 Feb 2022 13:13:37 -0800 Subject: riscv/mm: Add XIP_FIXUP for phys_ram_base This manifests as a crash early in boot on VexRiscv. Signed-off-by: Myrtle Shah [Palmer: split commit] Fixes: 6d7f91d914bc ("riscv: Get rid of CONFIG_PHYS_RAM_BASE in kernel physical address conversion") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/mm/init.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch') diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index cf4d018b7d66..eecfacac2cc5 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -522,6 +522,7 @@ static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size) } #ifdef CONFIG_XIP_KERNEL +#define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base)) extern char _xiprom[], _exiprom[], __data_loc; /* called from head.S with MMU off */ -- cgit v1.2.3 From ca0cb9a60f6d86d4b2139c6f393a78f39edcd7cb Mon Sep 17 00:00:00 2001 From: Palmer Dabbelt Date: Fri, 4 Feb 2022 13:14:08 -0800 Subject: riscv/mm: Add XIP_FIXUP for riscv_pfn_base This manifests as a crash early in boot on VexRiscv. Signed-off-by: Myrtle Shah [Palmer: split commit] Fixes: 44c922572952 ("RISC-V: enable XIP") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/mm/init.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch') diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index eecfacac2cc5..c27294128e18 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -232,6 +232,7 @@ static pmd_t __maybe_unused early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAG #ifdef CONFIG_XIP_KERNEL #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops)) +#define riscv_pfn_base (*(unsigned long *)XIP_FIXUP(&riscv_pfn_base)) #define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir)) #define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte)) #define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir)) -- cgit v1.2.3 From f81393a5b252df772b934cde81b7e16273afbd43 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Sun, 23 Jan 2022 17:04:17 +0800 Subject: riscv: extable: fix err reg writing in dedicated uaccess handler Mayuresh reported commit 20802d8d477d ("riscv: extable: add a dedicated uaccess handler") breaks the writev02 test case in LTP. This is due to the err reg isn't correctly set with the errno(-EFAULT in writev02 case). First of all, the err and zero regs are reg numbers rather than reg offsets in struct pt_regs; Secondly, regs_set_gpr() should write the regs when offset isn't zero(zero means epc) Fix it by correcting regs_set_gpr() logic and passing the correct reg offset to it. Reported-by: Mayuresh Chitale Fixes: 20802d8d477d ("riscv: extable: add a dedicated uaccess handler") Signed-off-by: Jisheng Zhang Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/mm/extable.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/riscv/mm/extable.c b/arch/riscv/mm/extable.c index 05978f78579f..35484d830fd6 100644 --- a/arch/riscv/mm/extable.c +++ b/arch/riscv/mm/extable.c @@ -33,7 +33,7 @@ static inline void regs_set_gpr(struct pt_regs *regs, unsigned int offset, if (unlikely(offset > MAX_REG_OFFSET)) return; - if (!offset) + if (offset) *(unsigned long *)((unsigned long)regs + offset) = val; } @@ -43,8 +43,8 @@ static bool ex_handler_uaccess_err_zero(const struct exception_table_entry *ex, int reg_err = FIELD_GET(EX_DATA_REG_ERR, ex->data); int reg_zero = FIELD_GET(EX_DATA_REG_ZERO, ex->data); - regs_set_gpr(regs, reg_err, -EFAULT); - regs_set_gpr(regs, reg_zero, 0); + regs_set_gpr(regs, reg_err * sizeof(unsigned long), -EFAULT); + regs_set_gpr(regs, reg_zero * sizeof(unsigned long), 0); regs->epc = get_ex_fixup(ex); return true; -- cgit v1.2.3 From f40fe31c01445f31253b15bef2412b33ae31093b Mon Sep 17 00:00:00 2001 From: Pingfan Liu Date: Sun, 23 Jan 2022 20:13:52 +0800 Subject: riscv: cpu-hotplug: clear cpu from numa map when teardown There is numa_add_cpu() when cpus online, accordingly, there should be numa_remove_cpu() when cpus offline. Signed-off-by: Pingfan Liu Fixes: 4f0e8eef772e ("riscv: Add numa support for riscv64 platform") Cc: stable@vger.kernel.org [Palmer: Add missing NUMA include] Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/cpu-hotplug.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch') diff --git a/arch/riscv/kernel/cpu-hotplug.c b/arch/riscv/kernel/cpu-hotplug.c index be7f05b542bb..f7a832e3a1d1 100644 --- a/arch/riscv/kernel/cpu-hotplug.c +++ b/arch/riscv/kernel/cpu-hotplug.c @@ -12,6 +12,7 @@ #include #include #include +#include #include bool cpu_has_hotplug(unsigned int cpu) @@ -40,6 +41,7 @@ int __cpu_disable(void) return ret; remove_cpu_topology(cpu); + numa_remove_cpu(cpu); set_cpu_online(cpu, false); irq_migrate_all_off_this_cpu(); -- cgit v1.2.3 From 6df2a016c0c8a3d0933ef33dd192ea6606b115e3 Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Wed, 26 Jan 2022 18:14:42 +0100 Subject: riscv: fix build with binutils 2.38 From version 2.38, binutils default to ISA spec version 20191213. This means that the csr read/write (csrr*/csrw*) instructions and fence.i instruction has separated from the `I` extension, become two standalone extensions: Zicsr and Zifencei. As the kernel uses those instruction, this causes the following build failure: CC arch/riscv/kernel/vdso/vgettimeofday.o <>/arch/riscv/include/asm/vdso/gettimeofday.h: Assembler messages: <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' The fix is to specify those extensions explicitely in -march. However as older binutils version do not support this, we first need to detect that. Signed-off-by: Aurelien Jarno Tested-by: Alexandre Ghiti Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/Makefile | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'arch') diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 8a107ed18b0d..7d81102cffd4 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -50,6 +50,12 @@ riscv-march-$(CONFIG_ARCH_RV32I) := rv32ima riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c + +# Newer binutils versions default to ISA spec version 20191213 which moves some +# instructions from the I extension to the Zicsr and Zifencei extensions. +toolchain-need-zicsr-zifencei := $(call cc-option-yn, -march=$(riscv-march-y)_zicsr_zifencei) +riscv-march-$(toolchain-need-zicsr-zifencei) := $(riscv-march-y)_zicsr_zifencei + KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y)) KBUILD_AFLAGS += -march=$(riscv-march-y) -- cgit v1.2.3