From: Kazuhito Hagio <k-hagio...@nec.com> Based on Bhupesh's patch and contains Pingfan's idea.
Signed-off-by: Bhupesh Sharma <bhsha...@redhat.com> Signed-off-by: Kazuhito Hagio <k-hagio...@nec.com> --- arch/arm64.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++++---------- makedumpfile.c | 2 ++ makedumpfile.h | 1 + 3 files changed, 83 insertions(+), 15 deletions(-) diff --git a/arch/arm64.c b/arch/arm64.c index 61ec89a..4ece19d 100644 --- a/arch/arm64.c +++ b/arch/arm64.c @@ -47,6 +47,8 @@ typedef struct { static int lpa_52_bit_support_available; static int pgtable_level; static int va_bits; +static int vabits_actual; +static int flipped_va; static unsigned long kimage_voffset; #define SZ_4K 4096 @@ -58,7 +60,6 @@ static unsigned long kimage_voffset; #define PAGE_OFFSET_42 ((0xffffffffffffffffUL) << 42) #define PAGE_OFFSET_47 ((0xffffffffffffffffUL) << 47) #define PAGE_OFFSET_48 ((0xffffffffffffffffUL) << 48) -#define PAGE_OFFSET_52 ((0xffffffffffffffffUL) << 52) #define pgd_val(x) ((x).pgd) #define pud_val(x) (pgd_val((x).pgd)) @@ -218,12 +219,20 @@ pmd_page_paddr(pmd_t pmd) #define pte_index(vaddr) (((vaddr) >> PAGESHIFT()) & (PTRS_PER_PTE - 1)) #define pte_offset(dir, vaddr) (pmd_page_paddr((*dir)) + pte_index(vaddr) * sizeof(pte_t)) +/* + * The linear kernel range starts at the bottom of the virtual address + * space. Testing the top bit for the start of the region is a + * sufficient check and avoids having to worry about the tag. + */ +#define is_linear_addr(addr) (flipped_va ? \ + (!((unsigned long)(addr) & (1UL << (vabits_actual - 1)))) : \ + (!!((unsigned long)(addr) & (1UL << (vabits_actual - 1))))) + static unsigned long long __pa(unsigned long vaddr) { - if (kimage_voffset == NOT_FOUND_NUMBER || - (vaddr >= PAGE_OFFSET)) - return (vaddr - PAGE_OFFSET + info->phys_base); + if (kimage_voffset == NOT_FOUND_NUMBER || is_linear_addr(vaddr)) + return ((vaddr & ~PAGE_OFFSET) + info->phys_base); else return (vaddr - kimage_voffset); } @@ -253,6 +262,7 @@ static int calculate_plat_config(void) (PAGESIZE() == SZ_64K && va_bits == 42)) { pgtable_level = 2; } else if ((PAGESIZE() == SZ_64K && va_bits == 48) || + (PAGESIZE() == SZ_64K && va_bits == 52) || (PAGESIZE() == SZ_4K && va_bits == 39) || (PAGESIZE() == SZ_16K && va_bits == 47)) { pgtable_level = 3; @@ -263,6 +273,7 @@ static int calculate_plat_config(void) PAGESIZE(), va_bits); return FALSE; } + DEBUG_MSG("pgtable_level: %d\n", pgtable_level); return TRUE; } @@ -383,22 +394,54 @@ get_va_bits_from_stext_arm64(void) return TRUE; } +static void +get_page_offset_arm64(void) +{ + ulong page_end; + int vabits_min; + + /* + * See arch/arm64/include/asm/memory.h for more details of + * the PAGE_OFFSET calculation. + */ + vabits_min = (va_bits > 48) ? 48 : va_bits; + page_end = -(1UL << (vabits_min - 1)); + + if (SYMBOL(_stext) > page_end) { + flipped_va = TRUE; + info->page_offset = -(1UL << vabits_actual); + } else { + flipped_va = FALSE; + info->page_offset = -(1UL << (vabits_actual - 1)); + } + + DEBUG_MSG("page_offset : %lx (from page_end check)\n", + info->page_offset); +} + int get_machdep_info_arm64(void) { + /* Check if va_bits is still not initialized. If still 0, call + * get_versiondep_info() to initialize the same. + */ + if (!va_bits) + get_versiondep_info_arm64(); + /* Determine if the PA address range is 52-bits: ARMv8.2-LPA */ if (NUMBER(MAX_PHYSMEM_BITS) != NOT_FOUND_NUMBER) { info->max_physmem_bits = NUMBER(MAX_PHYSMEM_BITS); + DEBUG_MSG("max_physmem_bits : %ld (vmcoreinfo)\n", info->max_physmem_bits); if (info->max_physmem_bits == 52) lpa_52_bit_support_available = 1; - } else - info->max_physmem_bits = 48; + } else { + if (va_bits == 52) + info->max_physmem_bits = 52; /* just guess */ + else + info->max_physmem_bits = 48; - /* Check if va_bits is still not initialized. If still 0, call - * get_versiondep_info() to initialize the same. - */ - if (!va_bits) - get_versiondep_info_arm64(); + DEBUG_MSG("max_physmem_bits : %ld (guess)\n", info->max_physmem_bits); + } if (!calculate_plat_config()) { ERRMSG("Can't determine platform config values\n"); @@ -409,7 +452,6 @@ get_machdep_info_arm64(void) info->section_size_bits = SECTIONS_SIZE_BITS; DEBUG_MSG("kimage_voffset : %lx\n", kimage_voffset); - DEBUG_MSG("max_physmem_bits : %ld\n", info->max_physmem_bits); DEBUG_MSG("section_size_bits: %ld\n", info->section_size_bits); return TRUE; @@ -444,10 +486,33 @@ get_versiondep_info_arm64(void) return FALSE; } - info->page_offset = (0xffffffffffffffffUL) << (va_bits - 1); + /* + * See TCR_EL1, Translation Control Register (EL1) register + * description in the ARMv8 Architecture Reference Manual. + * Basically, we can use the TCR_EL1.T1SZ + * value to determine the virtual addressing range supported + * in the kernel-space (i.e. vabits_actual) since Linux 5.9. + */ + if (NUMBER(TCR_EL1_T1SZ) != NOT_FOUND_NUMBER) { + vabits_actual = 64 - NUMBER(TCR_EL1_T1SZ); + DEBUG_MSG("vabits_actual : %d (vmcoreinfo)\n", vabits_actual); + } else if ((va_bits == 52) && (SYMBOL(mem_section) != NOT_FOUND_SYMBOL)) { + /* + * Linux 5.4 through 5.10 have the following linear space: + * 48-bit: 0xffff000000000000 - 0xffff7fffffffffff + * 58-bit: 0xfff0000000000000 - 0xfff7ffffffffffff + */ + if (SYMBOL(mem_section) & (1UL << (52 - 1))) + vabits_actual = 48; + else + vabits_actual = 52; + DEBUG_MSG("vabits_actual : %d (guess from mem_section)\n", vabits_actual); + } else { + vabits_actual = va_bits; + DEBUG_MSG("vabits_actual : %d (same as va_bits)\n", vabits_actual); + } - DEBUG_MSG("va_bits : %d\n", va_bits); - DEBUG_MSG("page_offset : %lx\n", info->page_offset); + get_page_offset_arm64(); return TRUE; } diff --git a/makedumpfile.c b/makedumpfile.c index fdfe437..37788ff 100644 --- a/makedumpfile.c +++ b/makedumpfile.c @@ -2396,6 +2396,7 @@ write_vmcoreinfo_data(void) WRITE_NUMBER("HUGETLB_PAGE_DTOR", HUGETLB_PAGE_DTOR); #ifdef __aarch64__ WRITE_NUMBER("VA_BITS", VA_BITS); + /* WRITE_NUMBER("TCR_EL1_T1SZ", TCR_EL1_T1SZ); should not exists */ WRITE_NUMBER_UNSIGNED("PHYS_OFFSET", PHYS_OFFSET); WRITE_NUMBER_UNSIGNED("kimage_voffset", kimage_voffset); #endif @@ -2838,6 +2839,7 @@ read_vmcoreinfo(void) READ_NUMBER("KERNEL_IMAGE_SIZE", KERNEL_IMAGE_SIZE); #ifdef __aarch64__ READ_NUMBER("VA_BITS", VA_BITS); + READ_NUMBER("TCR_EL1_T1SZ", TCR_EL1_T1SZ); READ_NUMBER_UNSIGNED("PHYS_OFFSET", PHYS_OFFSET); READ_NUMBER_UNSIGNED("kimage_voffset", kimage_voffset); #endif diff --git a/makedumpfile.h b/makedumpfile.h index 5f50080..a151da2 100644 --- a/makedumpfile.h +++ b/makedumpfile.h @@ -1999,6 +1999,7 @@ struct number_table { long KERNEL_IMAGE_SIZE; #ifdef __aarch64__ long VA_BITS; + long TCR_EL1_T1SZ; unsigned long PHYS_OFFSET; unsigned long kimage_voffset; #endif -- 2.9.3 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec