78 lines
3.2 KiB
Diff
78 lines
3.2 KiB
Diff
|
From eedf12d4758409c3c405f56edf3177a3955e1f67 Mon Sep 17 00:00:00 2001
|
||
|
|
From: Lianbo Jiang <lijiang@redhat.com>
|
||
|
|
Date: Wed, 6 Mar 2024 14:31:27 +0800
|
||
|
|
Subject: [PATCH] gdb: fix "p" command to print module variables correctly
|
||
|
|
|
||
|
|
Some objects format may potentially support copy relocations, but
|
||
|
|
currently the maybe_copied is always initialized to 0 in the symbol().
|
||
|
|
And the type is 'mst_file_bss', not always the 'mst_bss' or 'mst_data'
|
||
|
|
in the lookup_minimal_symbol_linkage(). For example:
|
||
|
|
|
||
|
|
(gdb) p *msymbol
|
||
|
|
$42 = {<general_symbol_info> = {m_name = 0x349812f "test_no_static", value = {ivalue = 8, block = 0x8,
|
||
|
|
bytes = 0x8 <error: Cannot access memory at address 0x8>, address = 8, common_block = 0x8, chain = 0x8}, language_specific = {
|
||
|
|
obstack = 0x0, demangled_name = 0x0}, m_language = language_auto, ada_mangled = 0, section = 20}, size = 4,
|
||
|
|
filename = 0x6db3440 "test_sanity.c", type = mst_file_bss, created_by_gdb = 0, target_flag_1 = 0, target_flag_2 = 0, has_size = 1,
|
||
|
|
maybe_copied = 0, name_set = 1, hash_next = 0x0, demangled_hash_next = 0x0}
|
||
|
|
|
||
|
|
This causes a problem that the 'p' command cannot work well as expected,
|
||
|
|
and emits an error or a bogus value:
|
||
|
|
|
||
|
|
crash> mod -s test_sanity /home/test_sanity.ko
|
||
|
|
MODULE NAME BASE SIZE OBJECT FILE
|
||
|
|
ffffffffc1084040 test_sanity ffffffffc1082000 16384 /home/test_sanity.ko
|
||
|
|
crash> p test_no_static
|
||
|
|
p: gdb request failed: p test_no_static
|
||
|
|
crash>
|
||
|
|
|
||
|
|
The issue occurs with Linux 6.2 and later or kernels that have kernel
|
||
|
|
commit 80e4c1cd42ff ("x86/retbleed: Add X86_FEATURE_CALL_DEPTH") and
|
||
|
|
configured with CONFIG_CALL_DEPTH_TRACKING=y, including RHEL9.3 and
|
||
|
|
later kernels.
|
||
|
|
|
||
|
|
With the patch:
|
||
|
|
crash> mod -s test_sanity /home/test_sanity.ko
|
||
|
|
MODULE NAME BASE SIZE OBJECT FILE
|
||
|
|
ffffffffc1084040 test_sanity ffffffffc1082000 16384 /home/test_sanity.ko
|
||
|
|
crash> p test_no_static
|
||
|
|
test_no_static = $1 = 5
|
||
|
|
crash>
|
||
|
|
|
||
|
|
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
|
||
|
|
---
|
||
|
|
gdb-10.2.patch | 24 ++++++++++++++++++++++++
|
||
|
|
1 file changed, 24 insertions(+)
|
||
|
|
|
||
|
|
diff --git a/gdb-10.2.patch b/gdb-10.2.patch
|
||
|
|
index 7416efed..3694b131 100644
|
||
|
|
--- a/gdb-10.2.patch
|
||
|
|
+++ b/gdb-10.2.patch
|
||
|
|
@@ -3237,3 +3237,27 @@ exit 0
|
||
|
|
|
||
|
|
for (compunit_symtab *cust : objfile->compunits ())
|
||
|
|
{
|
||
|
|
+--- gdb-10.2/gdb/minsyms.c.orig
|
||
|
|
++++ gdb-10.2/gdb/minsyms.c
|
||
|
|
+@@ -535,7 +535,9 @@ lookup_minimal_symbol_linkage (const char *name, struct objfile *objf)
|
||
|
|
+ {
|
||
|
|
+ if (strcmp (msymbol->linkage_name (), name) == 0
|
||
|
|
+ && (MSYMBOL_TYPE (msymbol) == mst_data
|
||
|
|
+- || MSYMBOL_TYPE (msymbol) == mst_bss))
|
||
|
|
++ || MSYMBOL_TYPE (msymbol) == mst_bss
|
||
|
|
++ || MSYMBOL_TYPE (msymbol) == mst_file_bss
|
||
|
|
++ || MSYMBOL_TYPE (msymbol) == mst_file_data))
|
||
|
|
+ return {msymbol, objfile};
|
||
|
|
+ }
|
||
|
|
+ }
|
||
|
|
+--- gdb-10.2/gdb/symtab.h.orig
|
||
|
|
++++ gdb-10.2/gdb/symtab.h
|
||
|
|
+@@ -1110,7 +1110,7 @@ struct symbol : public general_symbol_info, public allocate_on_obstack
|
||
|
|
+ is_objfile_owned (1),
|
||
|
|
+ is_argument (0),
|
||
|
|
+ is_inlined (0),
|
||
|
|
+- maybe_copied (0),
|
||
|
|
++ maybe_copied (1), /* The objfile potentially supports copy relocations. */
|
||
|
|
+ subclass (SYMBOL_NONE)
|
||
|
|
+ {
|
||
|
|
+ /* We can't use an initializer list for members of a base class, and
|