[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v6 05/14] gdb: Conditionally run GDB script logic for dynamically
From: |
Glenn Washburn |
Subject: |
[PATCH v6 05/14] gdb: Conditionally run GDB script logic for dynamically or statically positioned GRUB |
Date: |
Tue, 10 Jan 2023 15:50:32 -0600 |
There are broadly two classes of targets to consider when loading symbols
for GRUB, targets that determine where to load GRUB at runtime
(dynamically positioned) and those that do not (statically positioned).
For statically poisitioned targets, symbol loading is determined at link
time, so nothing more needs to be known to load the symbols. For
dynamically positioned targets, such as EFI targets, at runtime symbols
should be offset by an amount that depends on where the runtime chose to
load GRUB.
It is important to not load symbols statically for dynamic targets
because then when subsequently loading the symbols correctly one must
take care to remove the existing static symbols, otherwise there will be
two sets of symbols and GDB seems to prefer the ones loaded first (ie the
static ones).
Use autoconf variables to generate a gdb_grub for a particular target,
which conditionally run startup code depending on if the target uses
static or dynamic loading.
Signed-off-by: Glenn Washburn <development@efficientek.com>
---
grub-core/gdb_grub.in | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)
diff --git a/grub-core/gdb_grub.in b/grub-core/gdb_grub.in
index d525a5a11f..620d1def72 100644
--- a/grub-core/gdb_grub.in
+++ b/grub-core/gdb_grub.in
@@ -86,7 +86,20 @@ end
###
set confirm off
-file kernel.exec
-target remote :1234
-runtime_load_module
+# Note: On EFI and other platforms that load GRUB to an address that is
+# determined at runtime, the symbols in kernel.exec will be wrong.
+# However, we must start by loading some executable file or GDB will
+# fail.
+
+set $platform_efi = $_streq("@platform@", "efi")
+
+if $platform_efi
+ # Only load the executable file, not the symbols
+ exec-file kernel.exec
+else
+ file kernel.exec
+ runtime_load_module
+end
+
+target remote :1234
--
2.34.1
- [PATCH v6 00/14] GDB script fixes and improvements, Glenn Washburn, 2023/01/10
- [PATCH v6 01/14] gdb: Fix redirection issue in dump_module_sections, Glenn Washburn, 2023/01/10
- [PATCH v6 02/14] gdb: Prevent wrapping when writing to .segments.tmp, Glenn Washburn, 2023/01/10
- [PATCH v6 03/14] gdb: If no modules have been loaded, do not try to load module symbols, Glenn Washburn, 2023/01/10
- [PATCH v6 04/14] gdb: Move runtime module loading into runtime_load_module, Glenn Washburn, 2023/01/10
- [PATCH v6 05/14] gdb: Conditionally run GDB script logic for dynamically or statically positioned GRUB,
Glenn Washburn <=
- [PATCH v6 06/14] gdb: Only connect to remote target once when first sourced, Glenn Washburn, 2023/01/10
- [PATCH v6 07/14] gdb: Replace module symbol loading implementation with Python one, Glenn Washburn, 2023/01/10
- [PATCH v6 08/14] gdb: Add functions to make loading from dynamically positioned targets easier, Glenn Washburn, 2023/01/10
- [PATCH v6 09/14] gdb: Add more support for debugging on EFI platforms, Glenn Washburn, 2023/01/10
- [PATCH v6 10/14] gdb: Allow running user-defined commands at GRUB start, Glenn Washburn, 2023/01/10
- [PATCH v6 11/14] gdb: Fix issue with breakpoints defined before the GRUB image is loaded, Glenn Washburn, 2023/01/10
- [PATCH v6 12/14] gdb: Add extra early initialization symbols for i386-pc, Glenn Washburn, 2023/01/10
- [PATCH v6 13/14] gdb: Modify gdb prompt when running gdb_grub script, Glenn Washburn, 2023/01/10
- [PATCH v6 14/14] docs: Add debugging chapter to development documentation, Glenn Washburn, 2023/01/10