[Crash-utility] [PATCH] arm64: Add fallback option when vabits_actual is missing
After the commit 0d9b1ffefabe ("arm64: mm: make vabits_actual
a build time constant if possible") introduced in v5.19
Linux kernel, the crash will not find vabits_actual symbol.
Add a fallback option to initialize VA_BITS based on the
user supplied machdep options.
Tested ramdumps loading in both 6.0 and 5.15 kernels.
Signed-off-by: Pavankumar Kondeti <quic_pkondeti(a)quicinc.com>
---
arm64.c | 33 +++++++++++++++++++++++++--------
1 file changed, 25 insertions(+), 8 deletions(-)
diff --git a/arm64.c b/arm64.c
index c3e26a3..9d5d0bd 100644
--- a/arm64.c
+++ b/arm64.c
@@ -4588,6 +4588,27 @@ arm64_IS_VMALLOC_ADDR(ulong vaddr)
/* Return TRUE if we succeed, return FALSE on failure. */
static int
+arm64_set_va_bits_fallback(void)
+{
+ if (machdep->machspec->VA_BITS_ACTUAL) {
+ machdep->machspec->VA_BITS = machdep->machspec->VA_BITS_ACTUAL;
+ machdep->machspec->VA_START =
_VA_START(machdep->machspec->VA_BITS_ACTUAL);
+ return TRUE;
+ }
+
+ if (machdep->machspec->CONFIG_ARM64_VA_BITS) {
+ /* guess */
+ machdep->machspec->VA_BITS_ACTUAL =
machdep->machspec->CONFIG_ARM64_VA_BITS;
+ machdep->machspec->VA_BITS = machdep->machspec->CONFIG_ARM64_VA_BITS;
+ machdep->machspec->VA_START =
_VA_START(machdep->machspec->VA_BITS_ACTUAL);
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+/* Return TRUE if we succeed, return FALSE on failure. */
+static int
arm64_set_va_bits_by_tcr(void)
{
ulong value;
@@ -4648,14 +4669,8 @@ arm64_calc_VA_BITS(void)
else {
if (arm64_set_va_bits_by_tcr()) {
/* nothing */
- } else if (machdep->machspec->VA_BITS_ACTUAL) {
- machdep->machspec->VA_BITS = machdep->machspec->VA_BITS_ACTUAL;
- machdep->machspec->VA_START =
_VA_START(machdep->machspec->VA_BITS_ACTUAL);
- } else if (machdep->machspec->CONFIG_ARM64_VA_BITS) {
- /* guess */
- machdep->machspec->VA_BITS_ACTUAL =
machdep->machspec->CONFIG_ARM64_VA_BITS;
- machdep->machspec->VA_BITS = machdep->machspec->CONFIG_ARM64_VA_BITS;
- machdep->machspec->VA_START =
_VA_START(machdep->machspec->VA_BITS_ACTUAL);
+ } else if (arm64_set_va_bits_fallback()) {
+ /* nothing */
} else
error(FATAL, "cannot determine VA_BITS_ACTUAL\n");
}
@@ -4671,6 +4686,8 @@ arm64_calc_VA_BITS(void)
return;
} else if (arm64_set_va_bits_by_tcr()) {
return;
+ } else if (arm64_set_va_bits_fallback()) {
+ return;
}
if (!(sp = symbol_search("swapper_pg_dir")) &&
--
2.7.4