diff options
| author | Pingfan Liu <piliu@redhat.com> | 2022-01-18 15:48:11 +0800 |
|---|---|---|
| committer | Simon Horman <horms@verge.net.au> | 2022-01-24 10:05:20 +0100 |
| commit | 454395e18ff12d2728ee458695160e9ab4899e33 (patch) | |
| tree | 64b6b8e91d8974c7bcb2a526daad913685e75c16 | |
| parent | bde864387a104137ff3bd5f0871709846d5c7943 (diff) | |
| download | kexec-tools-454395e18ff12d2728ee458695160e9ab4899e33.tar.gz | |
arm64: read VA_BITS from kcore for 52-bits VA kernel
phys_to_virt() calculates virtual address. As a important factor,
page_offset is excepted to be accurate.
Since arm64 kernel exposes va_bits through vmcore, using it.
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Reviewed-by: Philipp Rudo <prudo@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
| -rw-r--r-- | kexec/arch/arm64/kexec-arm64.c | 34 | ||||
| -rw-r--r-- | util_lib/elf_info.c | 5 | ||||
| -rw-r--r-- | util_lib/include/elf_info.h | 1 |
3 files changed, 36 insertions, 4 deletions
diff --git a/kexec/arch/arm64/kexec-arm64.c b/kexec/arch/arm64/kexec-arm64.c index 0f8a768..e502be0 100644 --- a/kexec/arch/arm64/kexec-arm64.c +++ b/kexec/arch/arm64/kexec-arm64.c @@ -54,7 +54,7 @@ static bool try_read_phys_offset_from_kcore = false; /* Machine specific details. */ -static int va_bits; +static int va_bits = -1; static unsigned long page_offset; /* Global varables the core kexec routines expect. */ @@ -895,7 +895,18 @@ static inline void set_phys_offset(int64_t v, char *set_method) static int get_va_bits(void) { - unsigned long long stext_sym_addr = get_kernel_sym("_stext"); + unsigned long long stext_sym_addr; + + /* + * if already got from kcore + */ + if (va_bits != -1) + goto out; + + + /* For kernel older than v4.19 */ + fprintf(stderr, "Warning, can't get the VA_BITS from kcore\n"); + stext_sym_addr = get_kernel_sym("_stext"); if (stext_sym_addr == 0) { fprintf(stderr, "Can't get the symbol of _stext.\n"); @@ -919,6 +930,7 @@ static int get_va_bits(void) return -1; } +out: dbgprintf("va_bits : %d\n", va_bits); return 0; @@ -936,14 +948,27 @@ int get_page_offset(unsigned long *page_offset) if (ret < 0) return ret; - *page_offset = UINT64_MAX << (va_bits - 1); + if (va_bits < 52) + *page_offset = UINT64_MAX << (va_bits - 1); + else + *page_offset = UINT64_MAX << va_bits; + dbgprintf("page_offset : %lx\n", *page_offset); return 0; } +static void arm64_scan_vmcoreinfo(char *pos) +{ + const char *str; + + str = "NUMBER(VA_BITS)="; + if (memcmp(str, pos, strlen(str)) == 0) + va_bits = strtoul(pos + strlen(str), NULL, 10); +} + /** - * get_phys_offset_from_vmcoreinfo_pt_note - Helper for getting PHYS_OFFSET + * get_phys_offset_from_vmcoreinfo_pt_note - Helper for getting PHYS_OFFSET (and va_bits) * from VMCOREINFO note inside 'kcore'. */ @@ -956,6 +981,7 @@ static int get_phys_offset_from_vmcoreinfo_pt_note(long *phys_offset) return EFAILED; } + arch_scan_vmcoreinfo = arm64_scan_vmcoreinfo; ret = read_phys_offset_elf_kcore(fd, phys_offset); close(fd); diff --git a/util_lib/elf_info.c b/util_lib/elf_info.c index 5574c7f..d252eff 100644 --- a/util_lib/elf_info.c +++ b/util_lib/elf_info.c @@ -310,6 +310,8 @@ int get_pt_load(int idx, #define NOT_FOUND_LONG_VALUE (-1) +void (*arch_scan_vmcoreinfo)(char *pos); + void scan_vmcoreinfo(char *start, size_t size) { char *last = start + size - 1; @@ -551,6 +553,9 @@ void scan_vmcoreinfo(char *start, size_t size) } } + if (arch_scan_vmcoreinfo != NULL) + (*arch_scan_vmcoreinfo)(pos); + if (last_line) break; } diff --git a/util_lib/include/elf_info.h b/util_lib/include/elf_info.h index f550d86..fdf4c3d 100644 --- a/util_lib/include/elf_info.h +++ b/util_lib/include/elf_info.h @@ -31,5 +31,6 @@ int get_pt_load(int idx, int read_phys_offset_elf_kcore(int fd, long *phys_off); int read_elf(int fd); void dump_dmesg(int fd, void (*handler)(char*, unsigned int)); +extern void (*arch_scan_vmcoreinfo)(char *pos); #endif /* ELF_INFO_H */ |