* [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing
@ 2023-11-05 3:59 Di Chen
2023-11-20 16:05 ` Aaron Merey
0 siblings, 1 reply; 6+ messages in thread
From: Di Chen @ 2023-11-05 3:59 UTC (permalink / raw)
To: systemtap
[-- Attachment #1.1: Type: text/plain, Size: 2858 bytes --]
From 9273dc95658b109f048e4ec9b0fcde96e34f3419 Mon Sep 17 00:00:00 2001
From: Di Chen <dichen@redhat.com>
Date: Sun, 5 Nov 2023 11:23:50 +0800
Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol
version is missing
After calling module_info::update_symtab, function aliases will be
populated. Then the updated symtab will be used for symbol searching.
For the _IO_new_fopen familty with the aliases:
$ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@
@GLIBC_2.2.5
1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
@GLIBC_2.2.5
1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@
@GLIBC_2.2.5
1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64
3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen
4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16
_IO_new_fopen
5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
@GLIBC_2.2.5
7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@
@GLIBC_2.2.5
a) fopen@@GLIBC_2.2.5 exists in the updated symtab
b) fopen does not exist in the updated symtab
This PR is to add a version info padding when symbol cannot be found in
the updated symtab.
Signed-off-by: Di Chen <dichen@redhat.com>
---
dwflpp.cxx | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/dwflpp.cxx b/dwflpp.cxx
index a4f66440f..22e1479c9 100644
--- a/dwflpp.cxx
+++ b/dwflpp.cxx
@@ -1052,6 +1052,15 @@ dwflpp::iterate_over_functions<void>(int
(*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version info padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
@@ -1138,6 +1147,15 @@ dwflpp::iterate_single_function<void>(int
(*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version info padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
--
2.41.0
[-- Attachment #2: 0001-PR29997-Fix-the-symbol-aliases-search-failure-when-s.patch --]
[-- Type: text/x-patch, Size: 2856 bytes --]
From 9273dc95658b109f048e4ec9b0fcde96e34f3419 Mon Sep 17 00:00:00 2001
From: Di Chen <dichen@redhat.com>
Date: Sun, 5 Nov 2023 11:23:50 +0800
Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol
version is missing
After calling module_info::update_symtab, function aliases will be
populated. Then the updated symtab will be used for symbol searching.
For the _IO_new_fopen familty with the aliases:
$ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@@GLIBC_2.2.5
1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64
3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen
4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_new_fopen
5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
a) fopen@@GLIBC_2.2.5 exists in the updated symtab
b) fopen does not exist in the updated symtab
This PR is to add a version info padding when symbol cannot be found in
the updated symtab.
Signed-off-by: Di Chen <dichen@redhat.com>
---
dwflpp.cxx | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/dwflpp.cxx b/dwflpp.cxx
index a4f66440f..22e1479c9 100644
--- a/dwflpp.cxx
+++ b/dwflpp.cxx
@@ -1052,6 +1052,15 @@ dwflpp::iterate_over_functions<void>(int (*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version info padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
@@ -1138,6 +1147,15 @@ dwflpp::iterate_single_function<void>(int (*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version info padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
--
2.41.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing
2023-11-05 3:59 [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing Di Chen
@ 2023-11-20 16:05 ` Aaron Merey
2023-12-20 2:56 ` Di Chen
0 siblings, 1 reply; 6+ messages in thread
From: Aaron Merey @ 2023-11-20 16:05 UTC (permalink / raw)
To: Di Chen; +Cc: systemtap
Hi Di,
Thanks for working on this.
On Sun, Nov 5, 2023 at 12:00 AM Di Chen via Systemtap
<systemtap@sourceware.org> wrote:
>
> From 9273dc95658b109f048e4ec9b0fcde96e34f3419 Mon Sep 17 00:00:00 2001
> From: Di Chen <dichen@redhat.com>
> Date: Sun, 5 Nov 2023 11:23:50 +0800
> Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol
> version is missing
>
> After calling module_info::update_symtab, function aliases will be
> populated. Then the updated symtab will be used for symbol searching.
>
> For the _IO_new_fopen familty with the aliases:
>
> $ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
> 247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@
> @GLIBC_2.2.5
> 1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
> @GLIBC_2.2.5
> 1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@
> @GLIBC_2.2.5
> 1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64
> 3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen
> 4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16
> _IO_new_fopen
> 5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
> 7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
> @GLIBC_2.2.5
> 7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@
> @GLIBC_2.2.5
>
> a) fopen@@GLIBC_2.2.5 exists in the updated symtab
> b) fopen does not exist in the updated symtab
>
> This PR is to add a version info padding when symbol cannot be found in
> the updated symtab.
>
> Signed-off-by: Di Chen <dichen@redhat.com>
> ---
> dwflpp.cxx | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/dwflpp.cxx b/dwflpp.cxx
> index a4f66440f..22e1479c9 100644
> --- a/dwflpp.cxx
> +++ b/dwflpp.cxx
> @@ -1052,6 +1052,15 @@ dwflpp::iterate_over_functions<void>(int
> (*callback)(Dwarf_Die*, void*),
> }
>
> auto range = v->equal_range(function);
> + // version info padding if the symbol is not found
> + if (range.first == range.second)
> + {
> + std::string function_with_ver = function + "@";
> + for (auto it = v->begin(); it != v->end(); ++it)
> + if (it->first.find(function_with_ver) == 0)
> + function_with_ver = it->first;
> + range = v->equal_range(function_with_ver);
> + }
This fixes the bug for function names without wildcards. However
the bug can still be reproduced using function names with wildcards.
For example the following command incorrectly returns no results:
$ stap -L 'process("/lib64/libc.so.6").function("fo*en")'
We'll need additional '@' handling in the section of
dwflpp::iterate_over_functions that matches wildcards.
> if (range.first != range.second)
> {
> for (auto it = range.first; it != range.second; ++it)
> @@ -1138,6 +1147,15 @@ dwflpp::iterate_single_function<void>(int
> (*callback)(Dwarf_Die*, void*),
> }
>
> auto range = v->equal_range(function);
> + // version info padding if the symbol is not found
> + if (range.first == range.second)
> + {
> + std::string function_with_ver = function + "@";
> + for (auto it = v->begin(); it != v->end(); ++it)
> + if (it->first.find(function_with_ver) == 0)
> + function_with_ver = it->first;
> + range = v->equal_range(function_with_ver);
> + }
> if (range.first != range.second)
> {
> for (auto it = range.first; it != range.second; ++it)
> --
> 2.41.0
Aaron
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing
2023-11-20 16:05 ` Aaron Merey
@ 2023-12-20 2:56 ` Di Chen
2024-01-18 0:15 ` Aaron Merey
0 siblings, 1 reply; 6+ messages in thread
From: Di Chen @ 2023-12-20 2:56 UTC (permalink / raw)
To: Aaron Merey; +Cc: systemtap
[-- Attachment #1.1: Type: text/plain, Size: 8683 bytes --]
Hey Aaron,
I have added the wildcard handling for the PR29997.
From 0c95ce19272d6e13abf6f41c4ae29b6aa925ca20 Mon Sep 17 00:00:00 2001
From: Di Chen <dichen@redhat.com>
Date: Sun, 5 Nov 2023 11:23:50 +0800
Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol
version is missing
After calling module_info::update_symtab, function aliases will be
populated. Then the updated symtab will be used for symbol searching.
For the _IO_new_fopen familty with the aliases:
$ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@
@GLIBC_2.2.5
1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
@GLIBC_2.2.5
1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@
@GLIBC_2.2.5
1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64
3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen
4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16
_IO_new_fopen
5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
@GLIBC_2.2.5
7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@
@GLIBC_2.2.5
a) fopen@@GLIBC_2.2.5 exists in the updated symtab
b) fopen does not exist in the updated symtab
This PR is to add a version info padding when symbol cannot be found in
the updated symtab.
Signed-off-by: Di Chen <dichen@redhat.com>
---
dwflpp.cxx | 44 +++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 43 insertions(+), 1 deletion(-)
diff --git a/dwflpp.cxx b/dwflpp.cxx
index 9fccca0a9..044b0ca97 100644
--- a/dwflpp.cxx
+++ b/dwflpp.cxx
@@ -1055,6 +1055,15 @@ dwflpp::iterate_over_functions<void>(int
(*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
@@ -1098,7 +1107,10 @@ dwflpp::iterate_over_functions<void>(int
(*callback)(Dwarf_Die*, void*),
if (pending_interrupts) return DWARF_CB_ABORT;
const string& func_name = it->first;
Dwarf_Die& die = it->second;
- if (function_name_matches_pattern (func_name, function))
+
+ // version padding if the pattern is not matched
+ if ((function_name_matches_pattern (func_name, function)) ||
+ (function_name_matches_pattern (func_name, function + "@*")))
{
if (sess.verbose > 4)
clog << _F("function cache %s:%s match %s vs %s",
module_name.c_str(),
@@ -1141,6 +1153,15 @@ dwflpp::iterate_single_function<void>(int
(*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
@@ -1158,6 +1179,27 @@ dwflpp::iterate_single_function<void>(int
(*callback)(Dwarf_Die*, void*),
if (rc != DWARF_CB_OK) break;
}
}
+ else if (name_has_wildcard (function))
+ {
+ for (auto it = v->begin(); it != v->end(); ++it)
+ {
+ if (pending_interrupts) return DWARF_CB_ABORT;
+ const string& func_name = it->first;
+ Dwarf_Die& die = it->second;
+
+ // version padding if the pattern is not matched
+ if ((function_name_matches_pattern (func_name, function)) ||
+ (function_name_matches_pattern (func_name, function + "@*")))
+ {
+ if (sess.verbose > 4)
+ clog << _F("function cache %s:%s match %s vs %s",
module_name.c_str(),
+ cu_name().c_str(), func_name.c_str(),
function.c_str()) << endl;
+
+ rc = (*callback)(& die, data);
+ if (rc != DWARF_CB_OK) break;
+ }
+ }
+ }
// undo the focus_on_cu
this->cu = NULL;
--
2.41.0
On Tue, Nov 21, 2023 at 12:05 AM Aaron Merey <amerey@redhat.com> wrote:
> Hi Di,
>
> Thanks for working on this.
>
> On Sun, Nov 5, 2023 at 12:00 AM Di Chen via Systemtap
> <systemtap@sourceware.org> wrote:
> >
> > From 9273dc95658b109f048e4ec9b0fcde96e34f3419 Mon Sep 17 00:00:00 2001
> > From: Di Chen <dichen@redhat.com>
> > Date: Sun, 5 Nov 2023 11:23:50 +0800
> > Subject: [PATCH] PR29997: Fix the symbol aliases search failure when
> symbol
> > version is missing
> >
> > After calling module_info::update_symtab, function aliases will be
> > populated. Then the updated symtab will be used for symbol searching.
> >
> > For the _IO_new_fopen familty with the aliases:
> >
> > $ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
> > 247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@
> > @GLIBC_2.2.5
> > 1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
> > @GLIBC_2.2.5
> > 1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16
> _IO_fopen@
> > @GLIBC_2.2.5
> > 1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16
> _IO_fopen64
> > 3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16
> __new_fopen
> > 4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16
> > _IO_new_fopen
> > 5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
> > 7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
> > @GLIBC_2.2.5
> > 7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16
> _IO_fopen@
> > @GLIBC_2.2.5
> >
> > a) fopen@@GLIBC_2.2.5 exists in the updated symtab
> > b) fopen does not exist in the updated symtab
> >
> > This PR is to add a version info padding when symbol cannot be found in
> > the updated symtab.
> >
> > Signed-off-by: Di Chen <dichen@redhat.com>
> > ---
> > dwflpp.cxx | 18 ++++++++++++++++++
> > 1 file changed, 18 insertions(+)
> >
> > diff --git a/dwflpp.cxx b/dwflpp.cxx
> > index a4f66440f..22e1479c9 100644
> > --- a/dwflpp.cxx
> > +++ b/dwflpp.cxx
> > @@ -1052,6 +1052,15 @@ dwflpp::iterate_over_functions<void>(int
> > (*callback)(Dwarf_Die*, void*),
> > }
> >
> > auto range = v->equal_range(function);
> > + // version info padding if the symbol is not found
> > + if (range.first == range.second)
> > + {
> > + std::string function_with_ver = function + "@";
> > + for (auto it = v->begin(); it != v->end(); ++it)
> > + if (it->first.find(function_with_ver) == 0)
> > + function_with_ver = it->first;
> > + range = v->equal_range(function_with_ver);
> > + }
>
> This fixes the bug for function names without wildcards. However
> the bug can still be reproduced using function names with wildcards.
> For example the following command incorrectly returns no results:
>
> $ stap -L 'process("/lib64/libc.so.6").function("fo*en")'
>
> We'll need additional '@' handling in the section of
> dwflpp::iterate_over_functions that matches wildcards.
>
> > if (range.first != range.second)
> > {
> > for (auto it = range.first; it != range.second; ++it)
> > @@ -1138,6 +1147,15 @@ dwflpp::iterate_single_function<void>(int
> > (*callback)(Dwarf_Die*, void*),
> > }
> >
> > auto range = v->equal_range(function);
> > + // version info padding if the symbol is not found
> > + if (range.first == range.second)
> > + {
> > + std::string function_with_ver = function + "@";
> > + for (auto it = v->begin(); it != v->end(); ++it)
> > + if (it->first.find(function_with_ver) == 0)
> > + function_with_ver = it->first;
> > + range = v->equal_range(function_with_ver);
> > + }
> > if (range.first != range.second)
> > {
> > for (auto it = range.first; it != range.second; ++it)
> > --
> > 2.41.0
>
> Aaron
>
>
[-- Attachment #2: 0001-PR29997-Fix-the-symbol-aliases-search-failure-when-s.patch --]
[-- Type: text/x-patch, Size: 4585 bytes --]
From 0c95ce19272d6e13abf6f41c4ae29b6aa925ca20 Mon Sep 17 00:00:00 2001
From: Di Chen <dichen@redhat.com>
Date: Sun, 5 Nov 2023 11:23:50 +0800
Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol
version is missing
After calling module_info::update_symtab, function aliases will be
populated. Then the updated symtab will be used for symbol searching.
For the _IO_new_fopen familty with the aliases:
$ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@@GLIBC_2.2.5
1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64
3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen
4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_new_fopen
5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
a) fopen@@GLIBC_2.2.5 exists in the updated symtab
b) fopen does not exist in the updated symtab
This PR is to add a version info padding when symbol cannot be found in
the updated symtab.
Signed-off-by: Di Chen <dichen@redhat.com>
---
dwflpp.cxx | 44 +++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 43 insertions(+), 1 deletion(-)
diff --git a/dwflpp.cxx b/dwflpp.cxx
index 9fccca0a9..044b0ca97 100644
--- a/dwflpp.cxx
+++ b/dwflpp.cxx
@@ -1055,6 +1055,15 @@ dwflpp::iterate_over_functions<void>(int (*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
@@ -1098,7 +1107,10 @@ dwflpp::iterate_over_functions<void>(int (*callback)(Dwarf_Die*, void*),
if (pending_interrupts) return DWARF_CB_ABORT;
const string& func_name = it->first;
Dwarf_Die& die = it->second;
- if (function_name_matches_pattern (func_name, function))
+
+ // version padding if the pattern is not matched
+ if ((function_name_matches_pattern (func_name, function)) ||
+ (function_name_matches_pattern (func_name, function + "@*")))
{
if (sess.verbose > 4)
clog << _F("function cache %s:%s match %s vs %s", module_name.c_str(),
@@ -1141,6 +1153,15 @@ dwflpp::iterate_single_function<void>(int (*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
@@ -1158,6 +1179,27 @@ dwflpp::iterate_single_function<void>(int (*callback)(Dwarf_Die*, void*),
if (rc != DWARF_CB_OK) break;
}
}
+ else if (name_has_wildcard (function))
+ {
+ for (auto it = v->begin(); it != v->end(); ++it)
+ {
+ if (pending_interrupts) return DWARF_CB_ABORT;
+ const string& func_name = it->first;
+ Dwarf_Die& die = it->second;
+
+ // version padding if the pattern is not matched
+ if ((function_name_matches_pattern (func_name, function)) ||
+ (function_name_matches_pattern (func_name, function + "@*")))
+ {
+ if (sess.verbose > 4)
+ clog << _F("function cache %s:%s match %s vs %s", module_name.c_str(),
+ cu_name().c_str(), func_name.c_str(), function.c_str()) << endl;
+
+ rc = (*callback)(& die, data);
+ if (rc != DWARF_CB_OK) break;
+ }
+ }
+ }
// undo the focus_on_cu
this->cu = NULL;
--
2.41.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing
2023-12-20 2:56 ` Di Chen
@ 2024-01-18 0:15 ` Aaron Merey
2024-01-31 2:45 ` Di Chen
0 siblings, 1 reply; 6+ messages in thread
From: Aaron Merey @ 2024-01-18 0:15 UTC (permalink / raw)
To: Di Chen; +Cc: systemtap
Hi Di,
Thanks for the patch.
On Tue, Dec 19, 2023 at 9:56 PM Di Chen <dichen@redhat.com> wrote:
>
> Hey Aaron,
>
> I have added the wildcard handling for the PR29997.
>
> From 0c95ce19272d6e13abf6f41c4ae29b6aa925ca20 Mon Sep 17 00:00:00 2001
> From: Di Chen <dichen@redhat.com>
> Date: Sun, 5 Nov 2023 11:23:50 +0800
> Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol
> version is missing
>
> After calling module_info::update_symtab, function aliases will be
> populated. Then the updated symtab will be used for symbol searching.
>
> For the _IO_new_fopen familty with the aliases:
>
> $ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
> 247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@@GLIBC_2.2.5
> 1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
> 1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
> 1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64
> 3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen
> 4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_new_fopen
> 5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
> 7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
> 7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
>
> a) fopen@@GLIBC_2.2.5 exists in the updated symtab
> b) fopen does not exist in the updated symtab
>
> This PR is to add a version info padding when symbol cannot be found in
> the updated symtab.
>
> Signed-off-by: Di Chen <dichen@redhat.com>
> ---
> dwflpp.cxx | 44 +++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 43 insertions(+), 1 deletion(-)
>
> diff --git a/dwflpp.cxx b/dwflpp.cxx
> index 9fccca0a9..044b0ca97 100644
> --- a/dwflpp.cxx
> +++ b/dwflpp.cxx
> @@ -1055,6 +1055,15 @@ dwflpp::iterate_over_functions<void>(int (*callback)(Dwarf_Die*, void*),
> }
>
> auto range = v->equal_range(function);
> + // version padding if the symbol is not found
> + if (range.first == range.second)
> + {
> + std::string function_with_ver = function + "@";
> + for (auto it = v->begin(); it != v->end(); ++it)
> + if (it->first.find(function_with_ver) == 0)
> + function_with_ver = it->first;
> + range = v->equal_range(function_with_ver);
> + }
Just a nit but there should be another 2 spaces of indentation for the
lines between these braces.
> if (range.first != range.second)
> {
> for (auto it = range.first; it != range.second; ++it)
> @@ -1098,7 +1107,10 @@ dwflpp::iterate_over_functions<void>(int (*callback)(Dwarf_Die*, void*),
> if (pending_interrupts) return DWARF_CB_ABORT;
> const string& func_name = it->first;
> Dwarf_Die& die = it->second;
> - if (function_name_matches_pattern (func_name, function))
> +
> + // version padding if the pattern is not matched
> + if ((function_name_matches_pattern (func_name, function)) ||
> + (function_name_matches_pattern (func_name, function + "@*")))
Nice, this fixes the issue where names containing wildcards and version
info aren't found.
> {
> if (sess.verbose > 4)
> clog << _F("function cache %s:%s match %s vs %s", module_name.c_str(),
> @@ -1141,6 +1153,15 @@ dwflpp::iterate_single_function<void>(int (*callback)(Dwarf_Die*, void*),
> }
>
> auto range = v->equal_range(function);
> + // version padding if the symbol is not found
> + if (range.first == range.second)
> + {
> + std::string function_with_ver = function + "@";
> + for (auto it = v->begin(); it != v->end(); ++it)
> + if (it->first.find(function_with_ver) == 0)
> + function_with_ver = it->first;
> + range = v->equal_range(function_with_ver);
> + }
> if (range.first != range.second)
> {
> for (auto it = range.first; it != range.second; ++it)
> @@ -1158,6 +1179,27 @@ dwflpp::iterate_single_function<void>(int (*callback)(Dwarf_Die*, void*),
> if (rc != DWARF_CB_OK) break;
> }
> }
> + else if (name_has_wildcard (function))
> + {
> + for (auto it = v->begin(); it != v->end(); ++it)
> + {
> + if (pending_interrupts) return DWARF_CB_ABORT;
> + const string& func_name = it->first;
> + Dwarf_Die& die = it->second;
> +
> + // version padding if the pattern is not matched
> + if ((function_name_matches_pattern (func_name, function)) ||
> + (function_name_matches_pattern (func_name, function + "@*")))
> + {
> + if (sess.verbose > 4)
> + clog << _F("function cache %s:%s match %s vs %s", module_name.c_str(),
> + cu_name().c_str(), func_name.c_str(), function.c_str()) << endl;
> +
> + rc = (*callback)(& die, data);
> + if (rc != DWARF_CB_OK) break;
> + }
> + }
> + }
Do we need to include wildcard handling here? Since this function didn't
originally include any wildcard handling, I'd assume that searches for
names with wildcards would always go through dwflpp::iterate_over_functions
instead.
>
> // undo the focus_on_cu
> this->cu = NULL;
> --
> 2.41.0
I was also thinking about whether we should include "@" handling for
mangled C++ names as well in dwflpp::iterate_over_functions. I
experimented with trying to list probe points with mangled function names
that include version info. eu-readelf shows some mangled names with
"@<VERSION>" in the stap binary. However it looks like these names
never appear among the linkage_names from dwarf_linkage_name that are
searched for a match.
For example, "_ZSt24__throw_out_of_range_fmtPKcz@GLIBCXX_3.4.20" is
list by eu-readelf in my locally built stap binary but it doesn't
appear in a dump of linkage_names search during `stap -L
'process("/usr/local/bin/stap").function("_ZSt24__throw_out_of_range_fmtPKcz")'`.
This might be a bug or possibly a limitation of dwarf_linkage_name.
However this goes beyond the scope of your patch so it's ok to not
address this in your patch.
Aaron
~
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing
2024-01-18 0:15 ` Aaron Merey
@ 2024-01-31 2:45 ` Di Chen
2024-01-31 22:38 ` Aaron Merey
0 siblings, 1 reply; 6+ messages in thread
From: Di Chen @ 2024-01-31 2:45 UTC (permalink / raw)
To: Aaron Merey; +Cc: systemtap
[-- Attachment #1.1: Type: text/plain, Size: 7046 bytes --]
Thanks Aaron,
Re-submitted with:
1) Indentation improvement.
2) Remove the wildcard handling in "iterate_single_function".
3) Add examples in the commit message.
On Thu, Jan 18, 2024 at 8:15 AM Aaron Merey <amerey@redhat.com> wrote:
> Hi Di,
>
> Thanks for the patch.
>
> On Tue, Dec 19, 2023 at 9:56 PM Di Chen <dichen@redhat.com> wrote:
> >
> > Hey Aaron,
> >
> > I have added the wildcard handling for the PR29997.
> >
> > From 0c95ce19272d6e13abf6f41c4ae29b6aa925ca20 Mon Sep 17 00:00:00 2001
> > From: Di Chen <dichen@redhat.com>
> > Date: Sun, 5 Nov 2023 11:23:50 +0800
> > Subject: [PATCH] PR29997: Fix the symbol aliases search failure when
> symbol
> > version is missing
> >
> > After calling module_info::update_symtab, function aliases will be
> > populated. Then the updated symtab will be used for symbol searching.
> >
> > For the _IO_new_fopen familty with the aliases:
> >
> > $ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
> > 247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@
> @GLIBC_2.2.5
> > 1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
> @GLIBC_2.2.5
> > 1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16
> _IO_fopen@@GLIBC_2.2.5
> > 1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16
> _IO_fopen64
> > 3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16
> __new_fopen
> > 4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16
> _IO_new_fopen
> > 5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
> > 7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@
> @GLIBC_2.2.5
> > 7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16
> _IO_fopen@@GLIBC_2.2.5
> >
> > a) fopen@@GLIBC_2.2.5 exists in the updated symtab
> > b) fopen does not exist in the updated symtab
> >
> > This PR is to add a version info padding when symbol cannot be found in
> > the updated symtab.
> >
> > Signed-off-by: Di Chen <dichen@redhat.com>
> > ---
> > dwflpp.cxx | 44 +++++++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 43 insertions(+), 1 deletion(-)
> >
> > diff --git a/dwflpp.cxx b/dwflpp.cxx
> > index 9fccca0a9..044b0ca97 100644
> > --- a/dwflpp.cxx
> > +++ b/dwflpp.cxx
> > @@ -1055,6 +1055,15 @@ dwflpp::iterate_over_functions<void>(int
> (*callback)(Dwarf_Die*, void*),
> > }
> >
> > auto range = v->equal_range(function);
> > + // version padding if the symbol is not found
> > + if (range.first == range.second)
> > + {
> > + std::string function_with_ver = function + "@";
> > + for (auto it = v->begin(); it != v->end(); ++it)
> > + if (it->first.find(function_with_ver) == 0)
> > + function_with_ver = it->first;
> > + range = v->equal_range(function_with_ver);
> > + }
>
> Just a nit but there should be another 2 spaces of indentation for the
> lines between these braces.
>
> > if (range.first != range.second)
> > {
> > for (auto it = range.first; it != range.second; ++it)
> > @@ -1098,7 +1107,10 @@ dwflpp::iterate_over_functions<void>(int
> (*callback)(Dwarf_Die*, void*),
> > if (pending_interrupts) return DWARF_CB_ABORT;
> > const string& func_name = it->first;
> > Dwarf_Die& die = it->second;
> > - if (function_name_matches_pattern (func_name, function))
> > +
> > + // version padding if the pattern is not matched
> > + if ((function_name_matches_pattern (func_name, function)) ||
> > + (function_name_matches_pattern (func_name, function +
> "@*")))
>
> Nice, this fixes the issue where names containing wildcards and version
> info aren't found.
>
> > {
> > if (sess.verbose > 4)
> > clog << _F("function cache %s:%s match %s vs %s",
> module_name.c_str(),
> > @@ -1141,6 +1153,15 @@ dwflpp::iterate_single_function<void>(int
> (*callback)(Dwarf_Die*, void*),
> > }
> >
> > auto range = v->equal_range(function);
> > + // version padding if the symbol is not found
> > + if (range.first == range.second)
> > + {
> > + std::string function_with_ver = function + "@";
> > + for (auto it = v->begin(); it != v->end(); ++it)
> > + if (it->first.find(function_with_ver) == 0)
> > + function_with_ver = it->first;
> > + range = v->equal_range(function_with_ver);
> > + }
> > if (range.first != range.second)
> > {
> > for (auto it = range.first; it != range.second; ++it)
> > @@ -1158,6 +1179,27 @@ dwflpp::iterate_single_function<void>(int
> (*callback)(Dwarf_Die*, void*),
> > if (rc != DWARF_CB_OK) break;
> > }
> > }
> > + else if (name_has_wildcard (function))
> > + {
> > + for (auto it = v->begin(); it != v->end(); ++it)
> > + {
> > + if (pending_interrupts) return DWARF_CB_ABORT;
> > + const string& func_name = it->first;
> > + Dwarf_Die& die = it->second;
> > +
> > + // version padding if the pattern is not matched
> > + if ((function_name_matches_pattern (func_name, function)) ||
> > + (function_name_matches_pattern (func_name, function +
> "@*")))
> > + {
> > + if (sess.verbose > 4)
> > + clog << _F("function cache %s:%s match %s vs %s",
> module_name.c_str(),
> > + cu_name().c_str(), func_name.c_str(),
> function.c_str()) << endl;
> > +
> > + rc = (*callback)(& die, data);
> > + if (rc != DWARF_CB_OK) break;
> > + }
> > + }
> > + }
>
> Do we need to include wildcard handling here? Since this function didn't
> originally include any wildcard handling, I'd assume that searches for
> names with wildcards would always go through dwflpp::iterate_over_functions
> instead.
>
> >
> > // undo the focus_on_cu
> > this->cu = NULL;
> > --
> > 2.41.0
>
> I was also thinking about whether we should include "@" handling for
> mangled C++ names as well in dwflpp::iterate_over_functions. I
> experimented with trying to list probe points with mangled function names
> that include version info. eu-readelf shows some mangled names with
> "@<VERSION>" in the stap binary. However it looks like these names
> never appear among the linkage_names from dwarf_linkage_name that are
> searched for a match.
>
> For example, "_ZSt24__throw_out_of_range_fmtPKcz@GLIBCXX_3.4.20" is
> list by eu-readelf in my locally built stap binary but it doesn't
> appear in a dump of linkage_names search during `stap -L
>
> 'process("/usr/local/bin/stap").function("_ZSt24__throw_out_of_range_fmtPKcz")'`.
>
> This might be a bug or possibly a limitation of dwarf_linkage_name.
> However this goes beyond the scope of your patch so it's ok to not
> address this in your patch.
>
> Aaron
> ~
>
>
[-- Attachment #2: 0001-PR29997-Fix-the-symbol-aliases-search-failure-when-s.patch --]
[-- Type: text/x-patch, Size: 3761 bytes --]
From c1462a5b904d1aff044d76fc8c9717a243bb182e Mon Sep 17 00:00:00 2001
From: Di Chen <dichen@redhat.com>
Date: Wed, 31 Jan 2024 10:25:35 +0800
Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol
version is missing
After calling module_info::update_symtab, function aliases will be
populated. Then the updated symtab will be used for symbol searching.
For the _IO_new_fopen family with the aliases:
$ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440
247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@@GLIBC_2.2.5
1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64
3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen
4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_new_fopen
5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64
7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@@GLIBC_2.2.5
7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@@GLIBC_2.2.5
a) fopen@@GLIBC_2.2.5 exists in the updated symtab
b) fopen does not exist in the updated symtab
This PR is to add a version info padding when symbol cannot be found in
the updated symtab, so systemap can support searching symbol aliases like
this:
$ stap -L 'process("/lib64/libc.so.6").function("fopen")'
# And with wildcard, like this
$ stap -L 'process("/lib64/libc.so.6").function("fo*en")'
Signed-off-by: Di Chen <dichen@redhat.com>
---
dwflpp.cxx | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)
diff --git a/dwflpp.cxx b/dwflpp.cxx
index 9fccca0a9..26e9144cd 100644
--- a/dwflpp.cxx
+++ b/dwflpp.cxx
@@ -1055,6 +1055,15 @@ dwflpp::iterate_over_functions<void>(int (*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
@@ -1098,7 +1107,10 @@ dwflpp::iterate_over_functions<void>(int (*callback)(Dwarf_Die*, void*),
if (pending_interrupts) return DWARF_CB_ABORT;
const string& func_name = it->first;
Dwarf_Die& die = it->second;
- if (function_name_matches_pattern (func_name, function))
+
+ // version padding if the pattern is not matched
+ if ((function_name_matches_pattern (func_name, function)) ||
+ (function_name_matches_pattern (func_name, function + "@*")))
{
if (sess.verbose > 4)
clog << _F("function cache %s:%s match %s vs %s", module_name.c_str(),
@@ -1141,6 +1153,15 @@ dwflpp::iterate_single_function<void>(int (*callback)(Dwarf_Die*, void*),
}
auto range = v->equal_range(function);
+ // version padding if the symbol is not found
+ if (range.first == range.second)
+ {
+ std::string function_with_ver = function + "@";
+ for (auto it = v->begin(); it != v->end(); ++it)
+ if (it->first.find(function_with_ver) == 0)
+ function_with_ver = it->first;
+ range = v->equal_range(function_with_ver);
+ }
if (range.first != range.second)
{
for (auto it = range.first; it != range.second; ++it)
--
2.41.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing
2024-01-31 2:45 ` Di Chen
@ 2024-01-31 22:38 ` Aaron Merey
0 siblings, 0 replies; 6+ messages in thread
From: Aaron Merey @ 2024-01-31 22:38 UTC (permalink / raw)
To: Di Chen; +Cc: systemtap
Hi Di,
On Tue, Jan 30, 2024 at 9:45 PM Di Chen <dichen@redhat.com> wrote:
>
> Thanks Aaron,
>
> Re-submitted with:
> 1) Indentation improvement.
> 2) Remove the wildcard handling in "iterate_single_function".
> 3) Add examples in the commit message.
Thanks, pushed as commit 15d6d16f7d8.
Aaron
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2024-01-31 22:39 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-11-05 3:59 [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing Di Chen
2023-11-20 16:05 ` Aaron Merey
2023-12-20 2:56 ` Di Chen
2024-01-18 0:15 ` Aaron Merey
2024-01-31 2:45 ` Di Chen
2024-01-31 22:38 ` Aaron Merey
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