* [PATCH v2 0/2] RISC-V page table dumper @ 2020-02-10 8:35 Zong Li 2020-02-10 8:35 ` [PATCH v2 1/2] riscv: Add support to dump the kernel page tables Zong Li 2020-02-10 8:35 ` [PATCH v2 2/2] riscv: Use macro definition instead of magic number Zong Li 0 siblings, 2 replies; 5+ messages in thread From: Zong Li @ 2020-02-10 8:35 UTC (permalink / raw) To: paul.walmsley, palmer, aou, linux-riscv, linux-kernel; +Cc: Zong Li This patch contains the support for dumping the page tables, and it's implemented on top of the generic page table dumper patch set. The generic page table dumper patch set is merged at 5.6-rc1. This patch also depends on the fix about KASAN issue which causes the segmentation fault. (https://patchwork.kernel.org/patch/11372493/) Zong Li (2): riscv: Add support to dump the kernel page tables riscv: Use macro definition instead of magic number arch/riscv/Kconfig | 1 + arch/riscv/include/asm/kasan.h | 2 +- arch/riscv/include/asm/pgtable.h | 10 + arch/riscv/include/asm/ptdump.h | 11 ++ arch/riscv/mm/Makefile | 1 + arch/riscv/mm/ptdump.c | 317 +++++++++++++++++++++++++++++++ 6 files changed, 341 insertions(+), 1 deletion(-) create mode 100644 arch/riscv/include/asm/ptdump.h create mode 100644 arch/riscv/mm/ptdump.c -- 2.25.0 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v2 1/2] riscv: Add support to dump the kernel page tables 2020-02-10 8:35 [PATCH v2 0/2] RISC-V page table dumper Zong Li @ 2020-02-10 8:35 ` Zong Li 2020-03-10 5:40 ` Alex Ghiti 2020-02-10 8:35 ` [PATCH v2 2/2] riscv: Use macro definition instead of magic number Zong Li 1 sibling, 1 reply; 5+ messages in thread From: Zong Li @ 2020-02-10 8:35 UTC (permalink / raw) To: paul.walmsley, palmer, aou, linux-riscv, linux-kernel; +Cc: Zong Li 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. Changes in v2: - Remove #ifdef CONFIG_PTDUMP_CORE in header. Suggested by Steven Price. Signed-off-by: Zong Li <zong.li@sifive.com> --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/pgtable.h | 10 + arch/riscv/include/asm/ptdump.h | 11 ++ arch/riscv/mm/Makefile | 1 + arch/riscv/mm/ptdump.c | 317 +++++++++++++++++++++++++++++++ 5 files changed, 340 insertions(+) create mode 100644 arch/riscv/include/asm/ptdump.h create mode 100644 arch/riscv/mm/ptdump.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 73f029eae0cc..6e81da55b5e4 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -29,6 +29,7 @@ config RISCV select GENERIC_SMP_IDLE_THREAD select GENERIC_ATOMIC64 if !64BIT select GENERIC_IOREMAP + select GENERIC_PTDUMP select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_SECCOMP_FILTER select HAVE_ASM_MODVERSIONS diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index e43041519edd..ac353e44f80c 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -444,6 +444,16 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, #endif #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) +/* + * In the RV64 Linux scheme, we give the user half of the virtual-address space + * and give the kernel the other (upper) half. + */ +#ifdef CONFIG_64BIT +#define KERN_VIRT_START (-(BIT(CONFIG_VA_BITS)) + TASK_SIZE) +#else +#define KERN_VIRT_START FIXADDR_START +#endif + /* * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32. * Note that PGDIR_SIZE must evenly divide TASK_SIZE. diff --git a/arch/riscv/include/asm/ptdump.h b/arch/riscv/include/asm/ptdump.h new file mode 100644 index 000000000000..e29af7191909 --- /dev/null +++ b/arch/riscv/include/asm/ptdump.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 SiFive + */ + +#ifndef _ASM_RISCV_PTDUMP_H +#define _ASM_RISCV_PTDUMP_H + +void ptdump_check_wx(void); + +#endif /* _ASM_RISCV_PTDUMP_H */ diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile index 50b7af58c566..814e16a8d68a 100644 --- a/arch/riscv/mm/Makefile +++ b/arch/riscv/mm/Makefile @@ -15,6 +15,7 @@ ifeq ($(CONFIG_MMU),y) obj-$(CONFIG_SMP) += tlbflush.o endif obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o +obj-$(CONFIG_PTDUMP_CORE) += ptdump.o obj-$(CONFIG_KASAN) += kasan_init.o ifdef CONFIG_KASAN diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c new file mode 100644 index 000000000000..9a67e723fff7 --- /dev/null +++ b/arch/riscv/mm/ptdump.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2019 SiFive + */ + +#include <linux/init.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/ptdump.h> + +#include <asm/ptdump.h> +#include <asm/pgtable.h> +#include <asm/kasan.h> + +#define pt_dump_seq_printf(m, fmt, args...) \ +({ \ + if (m) \ + seq_printf(m, fmt, ##args); \ +}) + +#define pt_dump_seq_puts(m, fmt) \ +({ \ + if (m) \ + seq_printf(m, fmt); \ +}) + +/* + * The page dumper groups page table entries of the same type into a single + * description. It uses pg_state to track the range information while + * iterating over the pte entries. When the continuity is broken it then + * dumps out a description of the range. + */ +struct pg_state { + struct ptdump_state ptdump; + struct seq_file *seq; + const struct addr_marker *marker; + unsigned long start_address; + unsigned long start_pa; + unsigned long last_pa; + int level; + u64 current_prot; + bool check_wx; + unsigned long wx_pages; +}; + +/* Address marker */ +struct addr_marker { + unsigned long start_address; + const char *name; +}; + +static struct addr_marker address_markers[] = { +#ifdef CONFIG_KASAN + {KASAN_SHADOW_START, "Kasan shadow start"}, + {KASAN_SHADOW_END, "Kasan shadow end"}, +#endif + {FIXADDR_START, "Fixmap start"}, + {FIXADDR_TOP, "Fixmap end"}, + {PCI_IO_START, "PCI I/O start"}, + {PCI_IO_END, "PCI I/O end"}, +#ifdef CONFIG_SPARSEMEM_VMEMMAP + {VMEMMAP_START, "vmemmap start"}, + {VMEMMAP_END, "vmemmap end"}, +#endif + {VMALLOC_START, "vmalloc() area"}, + {VMALLOC_END, "vmalloc() end"}, + {PAGE_OFFSET, "Linear mapping"}, + {-1, NULL}, +}; + +/* Page Table Entry */ +struct prot_bits { + u64 mask; + u64 val; + const char *set; + const char *clear; +}; + +static const struct prot_bits pte_bits[] = { + { + .mask = _PAGE_SOFT, + .val = _PAGE_SOFT, + .set = "RSW", + .clear = " ", + }, { + .mask = _PAGE_DIRTY, + .val = _PAGE_DIRTY, + .set = "D", + .clear = ".", + }, { + .mask = _PAGE_ACCESSED, + .val = _PAGE_ACCESSED, + .set = "A", + .clear = ".", + }, { + .mask = _PAGE_GLOBAL, + .val = _PAGE_GLOBAL, + .set = "G", + .clear = ".", + }, { + .mask = _PAGE_USER, + .val = _PAGE_USER, + .set = "U", + .clear = ".", + }, { + .mask = _PAGE_EXEC, + .val = _PAGE_EXEC, + .set = "X", + .clear = ".", + }, { + .mask = _PAGE_WRITE, + .val = _PAGE_WRITE, + .set = "W", + .clear = ".", + }, { + .mask = _PAGE_READ, + .val = _PAGE_READ, + .set = "R", + .clear = ".", + }, { + .mask = _PAGE_PRESENT, + .val = _PAGE_PRESENT, + .set = "V", + .clear = ".", + } +}; + +/* Page Level */ +struct pg_level { + const char *name; + u64 mask; +}; + +static struct pg_level pg_level[] = { + { /* pgd */ + .name = "PGD", + }, { /* p4d */ + .name = (CONFIG_PGTABLE_LEVELS > 4) ? "P4D" : "PGD", + }, { /* pud */ + .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD", + }, { /* pmd */ + .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD", + }, { /* pte */ + .name = "PTE", + }, +}; + +static void dump_prot(struct pg_state *st) +{ + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(pte_bits); i++) { + const char *s; + + if ((st->current_prot & pte_bits[i].mask) == pte_bits[i].val) + s = pte_bits[i].set; + else + s = pte_bits[i].clear; + + if (s) + pt_dump_seq_printf(st->seq, " %s", s); + } +} + +#ifdef CONFIG_64BIT +#define ADDR_FORMAT "0x%016lx" +#else +#define ADDR_FORMAT "0x%08lx" +#endif +static void dump_addr(struct pg_state *st, unsigned long addr) +{ + static const char units[] = "KMGTPE"; + const char *unit = units; + unsigned long delta; + + pt_dump_seq_printf(st->seq, ADDR_FORMAT "-" ADDR_FORMAT " ", + st->start_address, addr); + + pt_dump_seq_printf(st->seq, " " ADDR_FORMAT " ", st->start_pa); + delta = (addr - st->start_address) >> 10; + + while (!(delta & 1023) && unit[1]) { + delta >>= 10; + unit++; + } + + pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit, + pg_level[st->level].name); +} + +static void note_prot_wx(struct pg_state *st, unsigned long addr) +{ + if (!st->check_wx) + return; + + if ((st->current_prot & (_PAGE_WRITE | _PAGE_EXEC)) != + (_PAGE_WRITE | _PAGE_EXEC)) + return; + + WARN_ONCE(1, "riscv/mm: Found insecure W+X mapping at address %p/%pS\n", + (void *)st->start_address, (void *)st->start_address); + + st->wx_pages += (addr - st->start_address) / PAGE_SIZE; +} + +static void note_page(struct ptdump_state *pt_st, unsigned long addr, + int level, unsigned long val) +{ + struct pg_state *st = container_of(pt_st, struct pg_state, ptdump); + u64 pa = PFN_PHYS(pte_pfn(__pte(val))); + u64 prot = 0; + + if (level >= 0) + prot = val & pg_level[level].mask; + + if (st->level == -1) { + st->level = level; + st->current_prot = prot; + st->start_address = addr; + st->start_pa = pa; + st->last_pa = pa; + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); + } else if (prot != st->current_prot || + level != st->level || addr >= st->marker[1].start_address) { + if (st->current_prot) { + note_prot_wx(st, addr); + dump_addr(st, addr); + dump_prot(st); + pt_dump_seq_puts(st->seq, "\n"); + } + + while (addr >= st->marker[1].start_address) { + st->marker++; + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", + st->marker->name); + } + + st->start_address = addr; + st->start_pa = pa; + st->last_pa = pa; + st->current_prot = prot; + st->level = level; + } else { + st->last_pa = pa; + } +} + +static void ptdump_walk(struct seq_file *s) +{ + struct pg_state st = { + .seq = s, + .marker = address_markers, + .level = -1, + .ptdump = { + .note_page = note_page, + .range = (struct ptdump_range[]) { + {KERN_VIRT_START, ULONG_MAX}, + {0, 0} + } + } + }; + + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); +} + +void ptdump_check_wx(void) +{ + struct pg_state st = { + .seq = NULL, + .marker = (struct addr_marker[]) { + {0, NULL}, + {-1, NULL}, + }, + .level = -1, + .check_wx = true, + .ptdump = { + .note_page = note_page, + .range = (struct ptdump_range[]) { + {KERN_VIRT_START, ULONG_MAX}, + {0, 0} + } + } + }; + + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); + + if (st.wx_pages) + pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found\n", + st.wx_pages); + else + pr_info("Checked W+X mappings: passed, no W+X pages found\n"); +} + +static int ptdump_show(struct seq_file *m, void *v) +{ + ptdump_walk(m); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(ptdump); + +static int ptdump_init(void) +{ + unsigned int i, j; + + for (i = 0; i < ARRAY_SIZE(pg_level); i++) + for (j = 0; j < ARRAY_SIZE(pte_bits); j++) + pg_level[i].mask |= pte_bits[j].mask; + + debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, + &ptdump_fops); + + return 0; +} + +device_initcall(ptdump_init); -- 2.25.0 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v2 1/2] riscv: Add support to dump the kernel page tables 2020-02-10 8:35 ` [PATCH v2 1/2] riscv: Add support to dump the kernel page tables Zong Li @ 2020-03-10 5:40 ` Alex Ghiti 2020-03-10 10:02 ` Zong Li 0 siblings, 1 reply; 5+ messages in thread From: Alex Ghiti @ 2020-03-10 5:40 UTC (permalink / raw) To: Zong Li, paul.walmsley, palmer, aou, linux-riscv, linux-kernel Hi Zong, On 2/10/20 3:35 AM, Zong Li wrote: > 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. > > Changes in v2: > - Remove #ifdef CONFIG_PTDUMP_CORE in header. Suggested by Steven Price. > > Signed-off-by: Zong Li <zong.li@sifive.com> > --- > arch/riscv/Kconfig | 1 + > arch/riscv/include/asm/pgtable.h | 10 + > arch/riscv/include/asm/ptdump.h | 11 ++ > arch/riscv/mm/Makefile | 1 + > arch/riscv/mm/ptdump.c | 317 +++++++++++++++++++++++++++++++ > 5 files changed, 340 insertions(+) > create mode 100644 arch/riscv/include/asm/ptdump.h > create mode 100644 arch/riscv/mm/ptdump.c > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 73f029eae0cc..6e81da55b5e4 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -29,6 +29,7 @@ config RISCV > select GENERIC_SMP_IDLE_THREAD > select GENERIC_ATOMIC64 if !64BIT > select GENERIC_IOREMAP > + select GENERIC_PTDUMP > select HAVE_ARCH_AUDITSYSCALL > select HAVE_ARCH_SECCOMP_FILTER > select HAVE_ASM_MODVERSIONS > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h > index e43041519edd..ac353e44f80c 100644 > --- a/arch/riscv/include/asm/pgtable.h > +++ b/arch/riscv/include/asm/pgtable.h > @@ -444,6 +444,16 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, > #endif > #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) > > +/* > + * In the RV64 Linux scheme, we give the user half of the virtual-address space > + * and give the kernel the other (upper) half. > + */ > +#ifdef CONFIG_64BIT > +#define KERN_VIRT_START (-(BIT(CONFIG_VA_BITS)) + TASK_SIZE) > +#else > +#define KERN_VIRT_START FIXADDR_START > +#endif > + > /* > * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32. > * Note that PGDIR_SIZE must evenly divide TASK_SIZE. > diff --git a/arch/riscv/include/asm/ptdump.h b/arch/riscv/include/asm/ptdump.h > new file mode 100644 > index 000000000000..e29af7191909 > --- /dev/null > +++ b/arch/riscv/include/asm/ptdump.h > @@ -0,0 +1,11 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (C) 2019 SiFive > + */ > + > +#ifndef _ASM_RISCV_PTDUMP_H > +#define _ASM_RISCV_PTDUMP_H > + > +void ptdump_check_wx(void); > + > +#endif /* _ASM_RISCV_PTDUMP_H */ > diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile > index 50b7af58c566..814e16a8d68a 100644 > --- a/arch/riscv/mm/Makefile > +++ b/arch/riscv/mm/Makefile > @@ -15,6 +15,7 @@ ifeq ($(CONFIG_MMU),y) > obj-$(CONFIG_SMP) += tlbflush.o > endif > obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o > +obj-$(CONFIG_PTDUMP_CORE) += ptdump.o > obj-$(CONFIG_KASAN) += kasan_init.o > > ifdef CONFIG_KASAN > diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c > new file mode 100644 > index 000000000000..9a67e723fff7 > --- /dev/null > +++ b/arch/riscv/mm/ptdump.c > @@ -0,0 +1,317 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2019 SiFive > + */ > + > +#include <linux/init.h> > +#include <linux/debugfs.h> > +#include <linux/seq_file.h> > +#include <linux/ptdump.h> > + > +#include <asm/ptdump.h> > +#include <asm/pgtable.h> > +#include <asm/kasan.h> > + > +#define pt_dump_seq_printf(m, fmt, args...) \ > +({ \ > + if (m) \ > + seq_printf(m, fmt, ##args); \ > +}) > + > +#define pt_dump_seq_puts(m, fmt) \ > +({ \ > + if (m) \ > + seq_printf(m, fmt); \ > +}) > + > +/* > + * The page dumper groups page table entries of the same type into a single > + * description. It uses pg_state to track the range information while > + * iterating over the pte entries. When the continuity is broken it then > + * dumps out a description of the range. > + */ > +struct pg_state { > + struct ptdump_state ptdump; > + struct seq_file *seq; > + const struct addr_marker *marker; > + unsigned long start_address; > + unsigned long start_pa; > + unsigned long last_pa; > + int level; > + u64 current_prot; > + bool check_wx; > + unsigned long wx_pages; > +}; > + > +/* Address marker */ > +struct addr_marker { > + unsigned long start_address; > + const char *name; > +}; > + > +static struct addr_marker address_markers[] = { > +#ifdef CONFIG_KASAN > + {KASAN_SHADOW_START, "Kasan shadow start"}, > + {KASAN_SHADOW_END, "Kasan shadow end"}, > +#endif > + {FIXADDR_START, "Fixmap start"}, > + {FIXADDR_TOP, "Fixmap end"}, > + {PCI_IO_START, "PCI I/O start"}, > + {PCI_IO_END, "PCI I/O end"}, > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > + {VMEMMAP_START, "vmemmap start"}, > + {VMEMMAP_END, "vmemmap end"}, > +#endif > + {VMALLOC_START, "vmalloc() area"}, > + {VMALLOC_END, "vmalloc() end"}, > + {PAGE_OFFSET, "Linear mapping"}, > + {-1, NULL}, > +}; > + > +/* Page Table Entry */ > +struct prot_bits { > + u64 mask; > + u64 val; > + const char *set; > + const char *clear; > +}; > + > +static const struct prot_bits pte_bits[] = { > + { > + .mask = _PAGE_SOFT, > + .val = _PAGE_SOFT, > + .set = "RSW", > + .clear = " ", > + }, { > + .mask = _PAGE_DIRTY, > + .val = _PAGE_DIRTY, > + .set = "D", > + .clear = ".", > + }, { > + .mask = _PAGE_ACCESSED, > + .val = _PAGE_ACCESSED, > + .set = "A", > + .clear = ".", > + }, { > + .mask = _PAGE_GLOBAL, > + .val = _PAGE_GLOBAL, > + .set = "G", > + .clear = ".", > + }, { > + .mask = _PAGE_USER, > + .val = _PAGE_USER, > + .set = "U", > + .clear = ".", > + }, { > + .mask = _PAGE_EXEC, > + .val = _PAGE_EXEC, > + .set = "X", > + .clear = ".", > + }, { > + .mask = _PAGE_WRITE, > + .val = _PAGE_WRITE, > + .set = "W", > + .clear = ".", > + }, { > + .mask = _PAGE_READ, > + .val = _PAGE_READ, > + .set = "R", > + .clear = ".", > + }, { > + .mask = _PAGE_PRESENT, > + .val = _PAGE_PRESENT, > + .set = "V", > + .clear = ".", > + } > +}; > + > +/* Page Level */ > +struct pg_level { > + const char *name; > + u64 mask; > +}; > + > +static struct pg_level pg_level[] = { > + { /* pgd */ > + .name = "PGD", > + }, { /* p4d */ > + .name = (CONFIG_PGTABLE_LEVELS > 4) ? "P4D" : "PGD", > + }, { /* pud */ > + .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD", > + }, { /* pmd */ > + .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD", > + }, { /* pte */ > + .name = "PTE", > + }, > +}; > + > +static void dump_prot(struct pg_state *st) > +{ > + unsigned int i; > + > + for (i = 0; i < ARRAY_SIZE(pte_bits); i++) { > + const char *s; > + > + if ((st->current_prot & pte_bits[i].mask) == pte_bits[i].val) > + s = pte_bits[i].set; > + else > + s = pte_bits[i].clear; > + > + if (s) > + pt_dump_seq_printf(st->seq, " %s", s); > + } > +} > + > +#ifdef CONFIG_64BIT > +#define ADDR_FORMAT "0x%016lx" > +#else > +#define ADDR_FORMAT "0x%08lx" > +#endif > +static void dump_addr(struct pg_state *st, unsigned long addr) > +{ > + static const char units[] = "KMGTPE"; > + const char *unit = units; > + unsigned long delta; > + > + pt_dump_seq_printf(st->seq, ADDR_FORMAT "-" ADDR_FORMAT " ", > + st->start_address, addr); > + > + pt_dump_seq_printf(st->seq, " " ADDR_FORMAT " ", st->start_pa); > + delta = (addr - st->start_address) >> 10; > + > + while (!(delta & 1023) && unit[1]) { > + delta >>= 10; > + unit++; > + } > + > + pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit, > + pg_level[st->level].name); > +} > + > +static void note_prot_wx(struct pg_state *st, unsigned long addr) > +{ > + if (!st->check_wx) > + return; > + > + if ((st->current_prot & (_PAGE_WRITE | _PAGE_EXEC)) != > + (_PAGE_WRITE | _PAGE_EXEC)) > + return; > + > + WARN_ONCE(1, "riscv/mm: Found insecure W+X mapping at address %p/%pS\n", > + (void *)st->start_address, (void *)st->start_address); > + > + st->wx_pages += (addr - st->start_address) / PAGE_SIZE; > +} > + > +static void note_page(struct ptdump_state *pt_st, unsigned long addr, > + int level, unsigned long val) > +{ > + struct pg_state *st = container_of(pt_st, struct pg_state, ptdump); > + u64 pa = PFN_PHYS(pte_pfn(__pte(val))); > + u64 prot = 0; > + > + if (level >= 0) > + prot = val & pg_level[level].mask; > + > + if (st->level == -1) { > + st->level = level; > + st->current_prot = prot; > + st->start_address = addr; > + st->start_pa = pa; > + st->last_pa = pa; > + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); > + } else if (prot != st->current_prot || > + level != st->level || addr >= st->marker[1].start_address) { > + if (st->current_prot) { > + note_prot_wx(st, addr); > + dump_addr(st, addr); > + dump_prot(st); > + pt_dump_seq_puts(st->seq, "\n"); > + } > + > + while (addr >= st->marker[1].start_address) { > + st->marker++; > + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", > + st->marker->name); > + } > + > + st->start_address = addr; > + st->start_pa = pa; > + st->last_pa = pa; > + st->current_prot = prot; > + st->level = level; > + } else { > + st->last_pa = pa; > + } > +} > + > +static void ptdump_walk(struct seq_file *s) > +{ > + struct pg_state st = { > + .seq = s, > + .marker = address_markers, > + .level = -1, > + .ptdump = { > + .note_page = note_page, > + .range = (struct ptdump_range[]) { > + {KERN_VIRT_START, ULONG_MAX}, > + {0, 0} > + } > + } > + }; > + > + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); > +} > + > +void ptdump_check_wx(void) > +{ > + struct pg_state st = { > + .seq = NULL, > + .marker = (struct addr_marker[]) { > + {0, NULL}, > + {-1, NULL}, > + }, > + .level = -1, > + .check_wx = true, > + .ptdump = { > + .note_page = note_page, > + .range = (struct ptdump_range[]) { > + {KERN_VIRT_START, ULONG_MAX}, > + {0, 0} > + } > + } > + }; > + > + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); > + > + if (st.wx_pages) > + pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found\n", "FAILED" should be lowercase like "passed" below (or the other way around). > + st.wx_pages); > + else > + pr_info("Checked W+X mappings: passed, no W+X pages found\n"); > +} > + > +static int ptdump_show(struct seq_file *m, void *v) > +{ > + ptdump_walk(m); > + > + return 0; > +} > + > +DEFINE_SHOW_ATTRIBUTE(ptdump); > + > +static int ptdump_init(void) > +{ > + unsigned int i, j; > + > + for (i = 0; i < ARRAY_SIZE(pg_level); i++) > + for (j = 0; j < ARRAY_SIZE(pte_bits); j++) > + pg_level[i].mask |= pte_bits[j].mask; > + > + debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, > + &ptdump_fops); > + > + return 0; > +} > + > +device_initcall(ptdump_init); > Other than the small comment above, I have tested it on my sv48 series (I had to do some small changes to adapt it, but nothing significant): ---[ Fixmap start ]--- 0xffff9dfffef00000-0xffff9dffff000000 0x0000000082200000 1M PTE D A . . . W R V ---[ Fixmap end ]--- ---[ PCI I/O start ]--- ---[ PCI I/O end ]--- ---[ vmalloc() area ]--- 0xffffa00000000000-0xffffa00004000000 0x000000000c000000 64M PTE D A . . . W R V 0xffffa00004001000-0xffffa00004002000 0x0000000010008000 4K PTE D A . . . W R V 0xffffa00004003000-0xffffa00004004000 0x0000000010007000 4K PTE D A . . . W R V 0xffffa00004005000-0xffffa00004006000 0x0000000010006000 4K PTE D A . . . W R V 0xffffa00004011000-0xffffa00004012000 0x0000000010000000 4K PTE D A . . . W R V 0xffffa0000401c000-0xffffa0000401f000 0x00000007af979000 12K PTE D A . . . W R V 0xffffbffffffbb000-0xffffbffffffbe000 0x00000007b030e000 12K PTE D A . . . W R V 0xffffbffffffcc000-0xffffbffffffcf000 0x00000007b0311000 12K PTE D A . . . W R V 0xffffbffffffdd000-0xffffbffffffe0000 0x00000007b0314000 12K PTE D A . . . W R V 0xffffbffffffee000-0xffffbfffffff1000 0x00000007b0317000 12K PTE D A . . . W R V ---[ vmalloc() end ]--- ---[ Linear mapping ]--- 0xffffc00000000000-0xffffc00752e00000 0x0000000080200000 29998M PMD D A . . X W R V You can then add: Tested-by: Alexandre Ghiti <alex@ghiti.fr> Thanks, Alex ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2 1/2] riscv: Add support to dump the kernel page tables 2020-03-10 5:40 ` Alex Ghiti @ 2020-03-10 10:02 ` Zong Li 0 siblings, 0 replies; 5+ messages in thread From: Zong Li @ 2020-03-10 10:02 UTC (permalink / raw) To: Alex Ghiti Cc: Paul Walmsley, Palmer Dabbelt, Albert Ou, linux-riscv, linux-kernel@vger.kernel.org List On Tue, Mar 10, 2020 at 1:40 PM Alex Ghiti <alex@ghiti.fr> wrote: > > Hi Zong, > > On 2/10/20 3:35 AM, Zong Li wrote: > > 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. > > > > Changes in v2: > > - Remove #ifdef CONFIG_PTDUMP_CORE in header. Suggested by Steven Price. > > > > Signed-off-by: Zong Li <zong.li@sifive.com> > > --- > > arch/riscv/Kconfig | 1 + > > arch/riscv/include/asm/pgtable.h | 10 + > > arch/riscv/include/asm/ptdump.h | 11 ++ > > arch/riscv/mm/Makefile | 1 + > > arch/riscv/mm/ptdump.c | 317 +++++++++++++++++++++++++++++++ > > 5 files changed, 340 insertions(+) > > create mode 100644 arch/riscv/include/asm/ptdump.h > > create mode 100644 arch/riscv/mm/ptdump.c > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > index 73f029eae0cc..6e81da55b5e4 100644 > > --- a/arch/riscv/Kconfig > > +++ b/arch/riscv/Kconfig > > @@ -29,6 +29,7 @@ config RISCV > > select GENERIC_SMP_IDLE_THREAD > > select GENERIC_ATOMIC64 if !64BIT > > select GENERIC_IOREMAP > > + select GENERIC_PTDUMP > > select HAVE_ARCH_AUDITSYSCALL > > select HAVE_ARCH_SECCOMP_FILTER > > select HAVE_ASM_MODVERSIONS > > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h > > index e43041519edd..ac353e44f80c 100644 > > --- a/arch/riscv/include/asm/pgtable.h > > +++ b/arch/riscv/include/asm/pgtable.h > > @@ -444,6 +444,16 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, > > #endif > > #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) > > > > +/* > > + * In the RV64 Linux scheme, we give the user half of the virtual-address space > > + * and give the kernel the other (upper) half. > > + */ > > +#ifdef CONFIG_64BIT > > +#define KERN_VIRT_START (-(BIT(CONFIG_VA_BITS)) + TASK_SIZE) > +#else > > +#define KERN_VIRT_START FIXADDR_START > > +#endif > > + > > /* > > * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32. > > * Note that PGDIR_SIZE must evenly divide TASK_SIZE. > > diff --git a/arch/riscv/include/asm/ptdump.h b/arch/riscv/include/asm/ptdump.h > > new file mode 100644 > > index 000000000000..e29af7191909 > > --- /dev/null > > +++ b/arch/riscv/include/asm/ptdump.h > > @@ -0,0 +1,11 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * Copyright (C) 2019 SiFive > > + */ > > + > > +#ifndef _ASM_RISCV_PTDUMP_H > > +#define _ASM_RISCV_PTDUMP_H > > + > > +void ptdump_check_wx(void); > > + > > +#endif /* _ASM_RISCV_PTDUMP_H */ > > diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile > > index 50b7af58c566..814e16a8d68a 100644 > > --- a/arch/riscv/mm/Makefile > > +++ b/arch/riscv/mm/Makefile > > @@ -15,6 +15,7 @@ ifeq ($(CONFIG_MMU),y) > > obj-$(CONFIG_SMP) += tlbflush.o > > endif > > obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o > > +obj-$(CONFIG_PTDUMP_CORE) += ptdump.o > > obj-$(CONFIG_KASAN) += kasan_init.o > > > > ifdef CONFIG_KASAN > > diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c > > new file mode 100644 > > index 000000000000..9a67e723fff7 > > --- /dev/null > > +++ b/arch/riscv/mm/ptdump.c > > @@ -0,0 +1,317 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * Copyright (C) 2019 SiFive > > + */ > > + > > +#include <linux/init.h> > > +#include <linux/debugfs.h> > > +#include <linux/seq_file.h> > > +#include <linux/ptdump.h> > > + > > +#include <asm/ptdump.h> > > +#include <asm/pgtable.h> > > +#include <asm/kasan.h> > > + > > +#define pt_dump_seq_printf(m, fmt, args...) \ > > +({ \ > > + if (m) \ > > + seq_printf(m, fmt, ##args); \ > > +}) > > + > > +#define pt_dump_seq_puts(m, fmt) \ > > +({ \ > > + if (m) \ > > + seq_printf(m, fmt); \ > > +}) > > + > > +/* > > + * The page dumper groups page table entries of the same type into a single > > + * description. It uses pg_state to track the range information while > > + * iterating over the pte entries. When the continuity is broken it then > > + * dumps out a description of the range. > > + */ > > +struct pg_state { > > + struct ptdump_state ptdump; > > + struct seq_file *seq; > > + const struct addr_marker *marker; > > + unsigned long start_address; > > + unsigned long start_pa; > > + unsigned long last_pa; > > + int level; > > + u64 current_prot; > > + bool check_wx; > > + unsigned long wx_pages; > > +}; > > + > > +/* Address marker */ > > +struct addr_marker { > > + unsigned long start_address; > > + const char *name; > > +}; > > + > > +static struct addr_marker address_markers[] = { > > +#ifdef CONFIG_KASAN > > + {KASAN_SHADOW_START, "Kasan shadow start"}, > > + {KASAN_SHADOW_END, "Kasan shadow end"}, > > +#endif > > + {FIXADDR_START, "Fixmap start"}, > > + {FIXADDR_TOP, "Fixmap end"}, > > + {PCI_IO_START, "PCI I/O start"}, > > + {PCI_IO_END, "PCI I/O end"}, > > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > > + {VMEMMAP_START, "vmemmap start"}, > > + {VMEMMAP_END, "vmemmap end"}, > > +#endif > > + {VMALLOC_START, "vmalloc() area"}, > > + {VMALLOC_END, "vmalloc() end"}, > > + {PAGE_OFFSET, "Linear mapping"}, > > + {-1, NULL}, > > +}; > > + > > +/* Page Table Entry */ > > +struct prot_bits { > > + u64 mask; > > + u64 val; > > + const char *set; > > + const char *clear; > > +}; > > + > > +static const struct prot_bits pte_bits[] = { > > + { > > + .mask = _PAGE_SOFT, > > + .val = _PAGE_SOFT, > > + .set = "RSW", > > + .clear = " ", > > + }, { > > + .mask = _PAGE_DIRTY, > > + .val = _PAGE_DIRTY, > > + .set = "D", > > + .clear = ".", > > + }, { > > + .mask = _PAGE_ACCESSED, > > + .val = _PAGE_ACCESSED, > > + .set = "A", > > + .clear = ".", > > + }, { > > + .mask = _PAGE_GLOBAL, > > + .val = _PAGE_GLOBAL, > > + .set = "G", > > + .clear = ".", > > + }, { > > + .mask = _PAGE_USER, > > + .val = _PAGE_USER, > > + .set = "U", > > + .clear = ".", > > + }, { > > + .mask = _PAGE_EXEC, > > + .val = _PAGE_EXEC, > > + .set = "X", > > + .clear = ".", > > + }, { > > + .mask = _PAGE_WRITE, > > + .val = _PAGE_WRITE, > > + .set = "W", > > + .clear = ".", > > + }, { > > + .mask = _PAGE_READ, > > + .val = _PAGE_READ, > > + .set = "R", > > + .clear = ".", > > + }, { > > + .mask = _PAGE_PRESENT, > > + .val = _PAGE_PRESENT, > > + .set = "V", > > + .clear = ".", > > + } > > +}; > > + > > +/* Page Level */ > > +struct pg_level { > > + const char *name; > > + u64 mask; > > +}; > > + > > +static struct pg_level pg_level[] = { > > + { /* pgd */ > > + .name = "PGD", > > + }, { /* p4d */ > > + .name = (CONFIG_PGTABLE_LEVELS > 4) ? "P4D" : "PGD", > > + }, { /* pud */ > > + .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD", > > + }, { /* pmd */ > > + .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD", > > + }, { /* pte */ > > + .name = "PTE", > > + }, > > +}; > > + > > +static void dump_prot(struct pg_state *st) > > +{ > > + unsigned int i; > > + > > + for (i = 0; i < ARRAY_SIZE(pte_bits); i++) { > > + const char *s; > > + > > + if ((st->current_prot & pte_bits[i].mask) == pte_bits[i].val) > > + s = pte_bits[i].set; > > + else > > + s = pte_bits[i].clear; > > + > > + if (s) > > + pt_dump_seq_printf(st->seq, " %s", s); > > + } > > +} > > + > > +#ifdef CONFIG_64BIT > > +#define ADDR_FORMAT "0x%016lx" > > +#else > > +#define ADDR_FORMAT "0x%08lx" > > +#endif > > +static void dump_addr(struct pg_state *st, unsigned long addr) > > +{ > > + static const char units[] = "KMGTPE"; > > + const char *unit = units; > > + unsigned long delta; > > + > > + pt_dump_seq_printf(st->seq, ADDR_FORMAT "-" ADDR_FORMAT " ", > > + st->start_address, addr); > > + > > + pt_dump_seq_printf(st->seq, " " ADDR_FORMAT " ", st->start_pa); > > + delta = (addr - st->start_address) >> 10; > > + > > + while (!(delta & 1023) && unit[1]) { > > + delta >>= 10; > > + unit++; > > + } > > + > > + pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit, > > + pg_level[st->level].name); > > +} > > + > > +static void note_prot_wx(struct pg_state *st, unsigned long addr) > > +{ > > + if (!st->check_wx) > > + return; > > + > > + if ((st->current_prot & (_PAGE_WRITE | _PAGE_EXEC)) != > > + (_PAGE_WRITE | _PAGE_EXEC)) > > + return; > > + > > + WARN_ONCE(1, "riscv/mm: Found insecure W+X mapping at address %p/%pS\n", > > + (void *)st->start_address, (void *)st->start_address); > > + > > + st->wx_pages += (addr - st->start_address) / PAGE_SIZE; > > +} > > + > > +static void note_page(struct ptdump_state *pt_st, unsigned long addr, > > + int level, unsigned long val) > > +{ > > + struct pg_state *st = container_of(pt_st, struct pg_state, ptdump); > > + u64 pa = PFN_PHYS(pte_pfn(__pte(val))); > > + u64 prot = 0; > > + > > + if (level >= 0) > > + prot = val & pg_level[level].mask; > > + > > + if (st->level == -1) { > > + st->level = level; > > + st->current_prot = prot; > > + st->start_address = addr; > > + st->start_pa = pa; > > + st->last_pa = pa; > > + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); > > + } else if (prot != st->current_prot || > > + level != st->level || addr >= st->marker[1].start_address) { > > + if (st->current_prot) { > > + note_prot_wx(st, addr); > > + dump_addr(st, addr); > > + dump_prot(st); > > + pt_dump_seq_puts(st->seq, "\n"); > > + } > > + > > + while (addr >= st->marker[1].start_address) { > > + st->marker++; > > + pt_dump_seq_printf(st->seq, "---[ %s ]---\n", > > + st->marker->name); > > + } > > + > > + st->start_address = addr; > > + st->start_pa = pa; > > + st->last_pa = pa; > > + st->current_prot = prot; > > + st->level = level; > > + } else { > > + st->last_pa = pa; > > + } > > +} > > + > > +static void ptdump_walk(struct seq_file *s) > > +{ > > + struct pg_state st = { > > + .seq = s, > > + .marker = address_markers, > > + .level = -1, > > + .ptdump = { > > + .note_page = note_page, > > + .range = (struct ptdump_range[]) { > > + {KERN_VIRT_START, ULONG_MAX}, > > + {0, 0} > > + } > > + } > > + }; > > + > > + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); > > +} > > + > > +void ptdump_check_wx(void) > > +{ > > + struct pg_state st = { > > + .seq = NULL, > > + .marker = (struct addr_marker[]) { > > + {0, NULL}, > > + {-1, NULL}, > > + }, > > + .level = -1, > > + .check_wx = true, > > + .ptdump = { > > + .note_page = note_page, > > + .range = (struct ptdump_range[]) { > > + {KERN_VIRT_START, ULONG_MAX}, > > + {0, 0} > > + } > > + } > > + }; > > + > > + ptdump_walk_pgd(&st.ptdump, &init_mm, NULL); > > + > > + if (st.wx_pages) > > + pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found\n", > > "FAILED" should be lowercase like "passed" below (or the other way around). OK, I'll change them to be consistent in next version. > > > + st.wx_pages); > > + else > > + pr_info("Checked W+X mappings: passed, no W+X pages found\n"); > > +} > > + > > +static int ptdump_show(struct seq_file *m, void *v) > > +{ > > + ptdump_walk(m); > > + > > + return 0; > > +} > > + > > +DEFINE_SHOW_ATTRIBUTE(ptdump); > > + > > +static int ptdump_init(void) > > +{ > > + unsigned int i, j; > > + > > + for (i = 0; i < ARRAY_SIZE(pg_level); i++) > > + for (j = 0; j < ARRAY_SIZE(pte_bits); j++) > > + pg_level[i].mask |= pte_bits[j].mask; > > + > > + debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, > > + &ptdump_fops); > > + > > + return 0; > > +} > > + > > +device_initcall(ptdump_init); > > > > Other than the small comment above, I have tested it on my sv48 series > (I had to do some small changes to adapt it, but nothing significant): OK, maybe you could help to add the changes in your sv48 patch series. > > ---[ Fixmap start ]--- > 0xffff9dfffef00000-0xffff9dffff000000 0x0000000082200000 1M > PTE D A . . . W R V > ---[ Fixmap end ]--- > ---[ PCI I/O start ]--- > ---[ PCI I/O end ]--- > ---[ vmalloc() area ]--- > 0xffffa00000000000-0xffffa00004000000 0x000000000c000000 64M > PTE D A . . . W R V > 0xffffa00004001000-0xffffa00004002000 0x0000000010008000 4K > PTE D A . . . W R V > 0xffffa00004003000-0xffffa00004004000 0x0000000010007000 4K > PTE D A . . . W R V > 0xffffa00004005000-0xffffa00004006000 0x0000000010006000 4K > PTE D A . . . W R V > 0xffffa00004011000-0xffffa00004012000 0x0000000010000000 4K > PTE D A . . . W R V > 0xffffa0000401c000-0xffffa0000401f000 0x00000007af979000 12K > PTE D A . . . W R V > 0xffffbffffffbb000-0xffffbffffffbe000 0x00000007b030e000 12K > PTE D A . . . W R V > 0xffffbffffffcc000-0xffffbffffffcf000 0x00000007b0311000 12K > PTE D A . . . W R V > 0xffffbffffffdd000-0xffffbffffffe0000 0x00000007b0314000 12K > PTE D A . . . W R V > 0xffffbffffffee000-0xffffbfffffff1000 0x00000007b0317000 12K > PTE D A . . . W R V > ---[ vmalloc() end ]--- > ---[ Linear mapping ]--- > 0xffffc00000000000-0xffffc00752e00000 0x0000000080200000 29998M > PMD D A . . X W R V > > You can then add: > > Tested-by: Alexandre Ghiti <alex@ghiti.fr> > Thank you for your testing. > Thanks, > > Alex ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v2 2/2] riscv: Use macro definition instead of magic number 2020-02-10 8:35 [PATCH v2 0/2] RISC-V page table dumper Zong Li 2020-02-10 8:35 ` [PATCH v2 1/2] riscv: Add support to dump the kernel page tables Zong Li @ 2020-02-10 8:35 ` Zong Li 1 sibling, 0 replies; 5+ messages in thread From: Zong Li @ 2020-02-10 8:35 UTC (permalink / raw) To: paul.walmsley, palmer, aou, linux-riscv, linux-kernel; +Cc: Zong Li The KERN_VIRT_START defines the start virtual address of kernel space. Use this macro instead of magic number. Signed-off-by: Zong Li <zong.li@sifive.com> --- arch/riscv/include/asm/kasan.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index eee6e6588b12..b47045cb85ce 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -13,7 +13,7 @@ #define KASAN_SHADOW_SCALE_SHIFT 3 #define KASAN_SHADOW_SIZE (UL(1) << (38 - KASAN_SHADOW_SCALE_SHIFT)) -#define KASAN_SHADOW_START 0xffffffc000000000 /* 2^64 - 2^38 */ +#define KASAN_SHADOW_START KERN_VIRT_START /* 2^64 - 2^38 */ #define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE) #define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ -- 2.25.0 ^ permalink raw reply related [flat|nested] 5+ messages in thread
end of thread, other threads:[~2020-03-10 10:03 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-02-10 8:35 [PATCH v2 0/2] RISC-V page table dumper Zong Li 2020-02-10 8:35 ` [PATCH v2 1/2] riscv: Add support to dump the kernel page tables Zong Li 2020-03-10 5:40 ` Alex Ghiti 2020-03-10 10:02 ` Zong Li 2020-02-10 8:35 ` [PATCH v2 2/2] riscv: Use macro definition instead of magic number Zong Li
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