kexec-tools/SOURCES/rhonly-kexec-tools-2.0.18-makedumpfile-arm64-Add-support-for-ARMv8.2-LVA-52-bi.patch
2021-09-09 19:42:40 +00:00

236 lines
7.2 KiB
Diff

From: Bhupesh Sharma <bhsharma@redhat.com>
Date: Wed, 6 Feb 2019 12:31:29 +0530
Subject: [PATCH] makedumpfile/arm64: Add support for ARMv8.2-LVA (52-bit
user-space VA support)
With ARMv8.2-LVA architecture extension availability, arm64 hardware
which supports this extension can support upto 52-bit virtual
addresses. It is specially useful for having a 52-bit user-space virtual
address space while the kernel can still retain 48-bit virtual
addresses.
Since at the moment we enable the support of this extension in the
kernel via a CONFIG flag (CONFIG_ARM64_USER_VA_BITS_52), so there are
no clear mechanisms in user-space to determine this CONFIG
flag value and use it to determine the user-space VA address range
values.
'makedumpfile' can instead use 'MAX_USER_VA_BITS' value to
determine the maximum virtual physical address supported by user-space.
If 'MAX_USER_VA_BITS' value is greater than 'VA_BITS' than we are
running a use-case where user-space is 52-bit and underlying kernel is
still 48-bit. The increased 'PTRS_PER_PGD' value for such cases can then
be calculated as is done by the underlying kernel (see kernel file
'arch/arm64/include/asm/pgtable-hwdef.h' for details):
#define PTRS_PER_PGD (1 << (MAX_USER_VA_BITS - PGDIR_SHIFT))
I have sent a kernel patch upstream to add 'MAX_USER_VA_BITS' to
vmcoreinfo for arm64 (see [0]).
This patch is in accordance with ARMv8 Architecture Reference Manual
version D.a
[0].
http://lists.infradead.org/pipermail/kexec/2019-February/022411.html
Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
---
arch/arm64.c | 109 ++++++++++++++++++++++++++++++++++++++++++---------------
makedumpfile.c | 2 ++
makedumpfile.h | 1 +
3 files changed, 83 insertions(+), 29 deletions(-)
diff --git a/makedumpfile-1.6.7/arch/arm64.c b/makedumpfile-1.6.7/arch/arm64.c
index 0535193..5fcf59d 100644
--- a/makedumpfile-1.6.7/arch/arm64.c
+++ b/makedumpfile-1.6.7/arch/arm64.c
@@ -41,6 +41,7 @@ typedef struct {
static int pgtable_level;
static int va_bits;
+static int max_user_va_bits;
static unsigned long kimage_voffset;
#define SZ_4K (4 * 1024)
@@ -61,7 +62,7 @@ static unsigned long kimage_voffset;
#define PAGE_MASK (~(PAGESIZE() - 1))
#define PGDIR_SHIFT ((PAGESHIFT() - 3) * pgtable_level + 3)
-#define PTRS_PER_PGD (1 << (va_bits - PGDIR_SHIFT))
+#define PTRS_PER_PGD (1 << ((max_user_va_bits) - PGDIR_SHIFT))
#define PUD_SHIFT get_pud_shift_arm64()
#define PUD_SIZE (1UL << PUD_SHIFT)
#define PUD_MASK (~(PUD_SIZE - 1))
@@ -73,6 +74,10 @@ static unsigned long kimage_voffset;
#define PTRS_PER_PMD PTRS_PER_PTE
#define PAGE_PRESENT (1 << 0)
+
+/*
+ * Section address mask and size definitions.
+ */
#define SECTIONS_SIZE_BITS 30
/* Highest possible physical address supported */
#define PHYS_MASK_SHIFT 48
@@ -284,14 +289,83 @@ get_stext_symbol(void)
return(found ? kallsym : FALSE);
}
+static int
+get_va_bits_from_stext_arm64(void)
+{
+ ulong _stext;
+
+ _stext = get_stext_symbol();
+ if (!_stext) {
+ ERRMSG("Can't get the symbol of _stext.\n");
+ return FALSE;
+ }
+
+ /* Derive va_bits as per arch/arm64/Kconfig */
+ if ((_stext & PAGE_OFFSET_36) == PAGE_OFFSET_36) {
+ va_bits = 36;
+ } else if ((_stext & PAGE_OFFSET_39) == PAGE_OFFSET_39) {
+ va_bits = 39;
+ } else if ((_stext & PAGE_OFFSET_42) == PAGE_OFFSET_42) {
+ va_bits = 42;
+ } else if ((_stext & PAGE_OFFSET_47) == PAGE_OFFSET_47) {
+ va_bits = 47;
+ } else if ((_stext & PAGE_OFFSET_48) == PAGE_OFFSET_48) {
+ va_bits = 48;
+ } else {
+ ERRMSG("Cannot find a proper _stext for calculating VA_BITS\n");
+ return FALSE;
+ }
+
+ DEBUG_MSG("va_bits : %d\n", va_bits);
+
+ return TRUE;
+}
+
+static void
+get_page_offset_arm64(void)
+{
+ info->page_offset = (0xffffffffffffffffUL) << (va_bits - 1);
+
+ DEBUG_MSG("page_offset : %lx\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 (NUMBER(VA_BITS) != NOT_FOUND_NUMBER) {
+ va_bits = NUMBER(VA_BITS);
+ DEBUG_MSG("va_bits : %d (vmcoreinfo)\n",
+ va_bits);
+ }
+
+ /* Check if va_bits is still not initialized. If still 0, call
+ * get_versiondep_info() to initialize the same from _stext
+ * symbol.
+ */
if (!va_bits)
- get_versiondep_info_arm64();
+ if (get_va_bits_from_stext_arm64() == ERROR)
+ return ERROR;
+
+ get_page_offset_arm64();
+
+ if (NUMBER(MAX_USER_VA_BITS) != NOT_FOUND_NUMBER) {
+ max_user_va_bits = NUMBER(MAX_USER_VA_BITS);
+ DEBUG_MSG("max_user_va_bits : %d (vmcoreinfo)\n",
+ max_user_va_bits);
+ }
+
+ /* Check if max_user_va_bits is still not initialized.
+ * If still 0, its not available in vmcoreinfo and its
+ * safe to initialize it with va_bits.
+ */
+ if (!max_user_va_bits) {
+ max_user_va_bits = va_bits;
+ DEBUG_MSG("max_user_va_bits : %d (default = va_bits)\n",
+ max_user_va_bits);
+ }
if (!calculate_plat_config()) {
ERRMSG("Can't determine platform config values\n");
@@ -330,34 +404,11 @@ get_xen_info_arm64(void)
int
get_versiondep_info_arm64(void)
{
- ulong _stext;
-
- _stext = get_stext_symbol();
- if (!_stext) {
- ERRMSG("Can't get the symbol of _stext.\n");
- return FALSE;
- }
-
- /* Derive va_bits as per arch/arm64/Kconfig */
- if ((_stext & PAGE_OFFSET_36) == PAGE_OFFSET_36) {
- va_bits = 36;
- } else if ((_stext & PAGE_OFFSET_39) == PAGE_OFFSET_39) {
- va_bits = 39;
- } else if ((_stext & PAGE_OFFSET_42) == PAGE_OFFSET_42) {
- va_bits = 42;
- } else if ((_stext & PAGE_OFFSET_47) == PAGE_OFFSET_47) {
- va_bits = 47;
- } else if ((_stext & PAGE_OFFSET_48) == PAGE_OFFSET_48) {
- va_bits = 48;
- } else {
- ERRMSG("Cannot find a proper _stext for calculating VA_BITS\n");
- return FALSE;
- }
-
- info->page_offset = (0xffffffffffffffffUL) << (va_bits - 1);
+ if (!va_bits)
+ if (get_va_bits_from_stext_arm64() == ERROR)
+ return ERROR;
- 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-1.6.7/makedumpfile.c b/makedumpfile-1.6.7/makedumpfile.c
index d76a435..c8906b5 100644
--- a/makedumpfile-1.6.7/makedumpfile.c
+++ b/makedumpfile-1.6.7/makedumpfile.c
@@ -2313,6 +2313,7 @@ write_vmcoreinfo_data(void)
WRITE_NUMBER("HUGETLB_PAGE_DTOR", HUGETLB_PAGE_DTOR);
#ifdef __aarch64__
+ WRITE_NUMBER("MAX_USER_VA_BITS", MAX_USER_VA_BITS);
WRITE_NUMBER("VA_BITS", VA_BITS);
WRITE_NUMBER_UNSIGNED("PHYS_OFFSET", PHYS_OFFSET);
WRITE_NUMBER_UNSIGNED("kimage_voffset", kimage_voffset);
@@ -2719,6 +2720,7 @@ read_vmcoreinfo(void)
READ_NUMBER("phys_base", phys_base);
READ_NUMBER("KERNEL_IMAGE_SIZE", KERNEL_IMAGE_SIZE);
#ifdef __aarch64__
+ READ_NUMBER("MAX_USER_VA_BITS", MAX_USER_VA_BITS);
READ_NUMBER("VA_BITS", VA_BITS);
READ_NUMBER_UNSIGNED("PHYS_OFFSET", PHYS_OFFSET);
READ_NUMBER_UNSIGNED("kimage_voffset", kimage_voffset);
diff --git a/makedumpfile-1.6.7/makedumpfile.h b/makedumpfile-1.6.7/makedumpfile.h
index 24b2f69..cccb52a 100644
--- a/makedumpfile-1.6.7/makedumpfile.h
+++ b/makedumpfile-1.6.7/makedumpfile.h
@@ -1937,6 +1937,7 @@ struct number_table {
long phys_base;
long KERNEL_IMAGE_SIZE;
#ifdef __aarch64__
+ long MAX_USER_VA_BITS;
long VA_BITS;
unsigned long PHYS_OFFSET;
unsigned long kimage_voffset;
--
2.7.5