Bug 589917

Summary:

bad dwarf cfi data in module-init-tools binary

Product:

Red Hat Enterprise Linux 6

Reporter:

Mark Wielaard <mjw>

Component:

module-init-tools

Assignee:

Jon Masters <jcm>

Status:

CLOSED CURRENTRELEASE

QA Contact:

Martin Cermak <mcermak>

Severity:

medium

Docs Contact:

Priority:

low

Version:

6.0

CC:

azelinka, mcermak, syeghiay

Target Milestone:

Target Release:

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Hardware:

All

OS:

Linux

Whiteboard:

Fixed In Version:

module-init-tools-3.9-10.el6

Doc Type:

Bug Fix

Doc Text:

Story Points:

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Clone Of:

Environment:

Last Closed:

2010-11-10 21:10:50 UTC

Type:

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Regression:

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Mount Type:

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Documentation:

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CRM:

Verified Versions:

Category:

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oVirt Team:

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RHEL 7.3 requirements from Atomic Host:

Cloudforms Team:

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Target Upstream Version:

Embargoed:

Bug Depends On:

Bug Blocks:

503551

Attachments:

Description	Flags
python script to check for bad cfi in a binary	none

Description Mark Wielaard 2010-05-07 10:01:02 UTC

Description of problem:

An old version of gcc generated bad dwarf cfi expressions. This would not impact the functioning of the package itself, but might make debugging the binary with gdb, or tracing with systemtap less practical. This isn't a very high priority. But if the package can be rebuild with a current toolchain, gcc-4.4.3-19.el6 or later, that would solve this issue. Background information: http://gcc.gnu.org/ml/gcc-patches/2010-04/msg01422.html This only affects a very small number of packages (and only the i686 binaries).

Version-Release number of selected component (if applicable):

module-init-tools-3.9-5.el6.i686 (/sbin/depmod, /sbin/insmod.static)

The attached check_cfi.py script (thanks to Petr Machata) can be used to check the output of readelf --debug-dump=frames to see whether the faulty dwarf cfi expressions are present in the binary. There should be no output, currently the output is:

readelf --debug-dump=frames /sbin/depmod | tail -n +3 | python check_cfi.py
['00000000', '00000014', '00000000', 'CIE']
   DW_CFA_def_cfa: r4 (esp) ofs 4
   DW_CFA_offset: r8 (eip) at cfa-4
   DW_CFA_nop
   DW_CFA_nop
['000004c4', '00000044', '000004c8', 'FDE', 'cie=00000000', 'pc=0804b460..0804c079']
   DW_CFA_advance_loc: 4 to 0804b464
>  DW_CFA_def_cfa: r1 (ecx) ofs 0
   DW_CFA_advance_loc: 9 to 0804b46d
   DW_CFA_expression: r5 (ebp) (DW_OP_breg5: 0)
   DW_CFA_advance_loc: 4 to 0804b471
>  DW_CFA_def_cfa_expression (DW_OP_breg5: -16; DW_OP_deref)
   DW_CFA_advance_loc: 9 to 0804b47a
   DW_CFA_expression: r3 (ebx) (DW_OP_breg5: -12)
   DW_CFA_expression: r6 (esi) (DW_OP_breg5: -8)
   DW_CFA_expression: r7 (edi) (DW_OP_breg5: -4)
   DW_CFA_advance_loc2: 2084 to 0804bc9e
   DW_CFA_remember_state
>  DW_CFA_def_cfa_register: r1 (ecx)
   DW_CFA_advance_loc: 1 to 0804bc9f
   DW_CFA_restore: r3 (ebx)
   DW_CFA_advance_loc: 1 to 0804bca0
   DW_CFA_restore: r6 (esi)
   DW_CFA_advance_loc: 1 to 0804bca1
   DW_CFA_restore: r7 (edi)
   DW_CFA_advance_loc: 1 to 0804bca2
   DW_CFA_restore: r5 (ebp)
   DW_CFA_advance_loc: 3 to 0804bca5
   DW_CFA_def_cfa: r4 (esp) ofs 4
   DW_CFA_advance_loc: 3 to 0804bca8
   DW_CFA_restore_state
   DW_CFA_nop
   DW_CFA_nop
   DW_CFA_nop
error in instr #16, DW_CFA_def_cfa_register

readelf --debug-dump=frames /sbin/insmod.static | tail -n +3 | python check_cfi.py
['00000000', '00000014', '00000000', 'CIE']
   DW_CFA_def_cfa: r4 (esp) ofs 4
   DW_CFA_offset: r8 (eip) at cfa-4
   DW_CFA_nop
   DW_CFA_nop
['00006460', '00000040', '00006464', 'FDE', 'cie=00000000', 'pc=08075460..08079eb7']
   DW_CFA_advance_loc: 4 to 08075464
>  DW_CFA_def_cfa: r1 (ecx) ofs 0
   DW_CFA_advance_loc: 16 to 08075474
   DW_CFA_expression: r5 (ebp) (DW_OP_breg5: 0)
   DW_CFA_advance_loc: 13 to 08075481
>  DW_CFA_def_cfa_expression (DW_OP_breg5: -16; DW_OP_deref)
   DW_CFA_advance_loc: 26 to 0807549b
   DW_CFA_expression: r7 (edi) (DW_OP_breg5: -4)
   DW_CFA_expression: r6 (esi) (DW_OP_breg5: -8)
   DW_CFA_expression: r3 (ebx) (DW_OP_breg5: -12)
   DW_CFA_advance_loc2: 390 to 08075621
   DW_CFA_remember_state
>  DW_CFA_def_cfa_register: r1 (ecx)
   DW_CFA_advance_loc: 13 to 0807562e
   DW_CFA_restore: r7 (edi)
   DW_CFA_restore: r6 (esi)
   DW_CFA_restore: r3 (ebx)
   DW_CFA_advance_loc: 1 to 0807562f
   DW_CFA_restore: r5 (ebp)
   DW_CFA_advance_loc: 3 to 08075632
   DW_CFA_def_cfa: r4 (esp) ofs 4
   DW_CFA_advance_loc: 6 to 08075638
   DW_CFA_restore_state
   DW_CFA_nop
error in instr #16, DW_CFA_def_cfa_register

[...]

Comment 1 Mark Wielaard 2010-05-07 10:24:25 UTC

Created attachment 412291 [details]
python script to check for bad cfi in a binary

Comment 3 RHEL Program Management 2010-05-07 11:31:18 UTC

This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux major release.  Product Management has requested further
review of this request by Red Hat Engineering, for potential inclusion in a Red
Hat Enterprise Linux Major release.  This request is not yet committed for
inclusion.

Comment 4 Jon Masters 2010-05-18 18:03:01 UTC

I do plan to rebuild the package prior to beta2 anyway, so I am assuming that will be sufficient, given the toolchain fixes cited.

Comment 5 Mark Wielaard 2010-05-18 18:26:21 UTC

(In reply to comment #4)
> I do plan to rebuild the package prior to beta2 anyway, so I am assuming that
> will be sufficient, given the toolchain fixes cited.    

Yes, that would do it. Thanks.

Comment 6 Jon Masters 2010-05-18 23:01:07 UTC

No problem!

Comment 14 Martin Cermak 2010-09-24 08:26:03 UTC

=> VERIFIED

Comment 15 Jon Masters 2010-09-30 04:40:48 UTC

Thanks

Comment 16 releng-rhel@redhat.com 2010-11-10 21:10:50 UTC

Red Hat Enterprise Linux 6.0 is now available and should resolve
the problem described in this bug report. This report is therefore being closed
with a resolution of CURRENTRELEASE. You may reopen this bug report if the
solution does not work for you.