From: Glenn Washburn Date: Mon, 27 Feb 2023 21:15:32 +0000 (-0600) Subject: gdb: Conditionally run GDB script logic for dynamically or statically positioned... X-Git-Tag: grub-2.12-rc1~112 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=99ccf5b2450854f3fc1c26844cc6e9403243d8de;p=thirdparty%2Fgrub.git gdb: Conditionally run GDB script logic for dynamically or statically positioned GRUB 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 positioned 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 (i.e. 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 Reviewed-by: Daniel Kiper --- diff --git a/grub-core/gdb_grub.in b/grub-core/gdb_grub.in index d525a5a11..620d1def7 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