Re: [pushed] [gdb/testsuite] Use maint ignore-probes in gdb.base/longjmp.exp

[Luis Machado <luis.machado@arm.com>]

On 2/8/23 14:48, Tom de Vries wrote:
> On 2/8/23 14:27, Luis Machado wrote:
>> Hi Tom,
>>
>> Is the entire test supposed to PASS? I'm seeing the following on my aarch64/Ubuntu 22.04 setup:
>>
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 2: next over call_longjmp (the program is no longer running)
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 2: next over setjmp (the program is no longer running)
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 2: setup: breakpoint at pattern start (got interactive prompt)
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 2: setup: breakpoint at safety net (got interactive prompt)
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 2: setup: continue to breakpoint at pattern start (the program exited)
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 3: next over pattern (the program is no longer running)
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 3: setup: breakpoint at pattern start (got interactive prompt)
>> FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 3: setup: continue to breakpoint at pattern start (the program is no longer running)
>>
>> Maybe something is genuinely broken for aarch64 though, or I'm missing some packages/debuginfo.
> 
> Hi,
> 
> I just ran this test-case on openSUSE Leap 15.4 aarch64, no problems found.
> 

Alright. That's good to know.

>>
>> This part in particular seems a bit off:
>>
>> (gdb) break 63
>> No line 63 in the current file.
>> Make breakpoint pending on future shared library load? (y or [n]) n
>> (gdb) FAIL: gdb.base/longjmp.exp: with_probes=0: pattern 2: setup: breakpoint at pattern start (got interactive prompt)
>>
> 
> I'd focus on the first FAIL.  Why is the safety net breakpoint not triggering?

Yeah, it seems a bit fishy. I'll take a look. Thanks!

> 
> Thanks,
> - Tom
> 
>> On 2/8/23 12:46, Tom de Vries via Gdb-patches wrote:
>>> Test-case gdb.base/longjmp.exp handles both the case that there is a libc
>>> longjmp probe, and the case that there isn't.
>>>
>>> However, it only tests one of the two cases.
>>>
>>> Use maint ignore-probes to test both cases, if possible.
>>>
>>> Tested on x86_64-linux.
>>> ---
>>>   gdb/testsuite/gdb.base/longjmp.exp | 295 +++++++++++++++--------------
>>>   1 file changed, 157 insertions(+), 138 deletions(-)
>>>
>>> diff --git a/gdb/testsuite/gdb.base/longjmp.exp b/gdb/testsuite/gdb.base/longjmp.exp
>>> index 27a60bc4502..96d9c1c8059 100644
>>> --- a/gdb/testsuite/gdb.base/longjmp.exp
>>> +++ b/gdb/testsuite/gdb.base/longjmp.exp
>>> @@ -25,181 +25,200 @@ if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {deb
>>>        return -1
>>>   }
>>> -clean_restart ${binfile}
>>> +proc do_test { with_probes } {
>>> +    clean_restart ${::binfile}
>>> -if {![runto_main]} {
>>> -   return 0
>>> -}
>>> +    if { !$with_probes } {
>>> +    gdb_test "maint ignore-probes libc ^longjmp$"
>>> +    }
>>> -# With a libc with probes, all tests should pass.
>>> -#
>>> -# Without probes, we can still set a break on longjmp, but getting the longjmp
>>> -# target may not work, in the following cases:
>>> -# - gdbarch_get_longjmp_target_p (gdbarch) == 0: not implemented.
>>> -# - gdbarch_get_longjmp_target (gdbarch) == 0: for instance on amd64 if
>>> -#   tdep->jb_pc_offset == -1.
>>> -# - gdbarch_get_longjmp_target (gdbarch) != 0: if we have a glibc with
>>> -#   pointer mangling ( https://sourceware.org/glibc/wiki/PointerEncryption )
>>> -#   then we retrieve a mangled longjmp target that needs to be demangled.
>>> -#   For instance on amd64 with target board unix/-m32.
>>> -#
>>> -# Pointer demangling is currently not implemented for any target.
>>> -# For the amd64 case, this would require copying for instance this:
>>> -#   48 c1 ca 11             ror    $0x11,%rdx
>>> -#   64 48 33 14 25 30 00    xor    %fs:0x30,%rdx
>>> -# into a scratch space, save the register set, set %rdx to the mangled
>>> -# longjmp target, displaced-step through the two insn and read the
>>> -# demangled longjmp target from %rdx, and restore the register set.
>>> -#
>>> -# The failure mode in the first two cases is that the next degrades into a
>>> -# continue.  The failure mode in the latter case is a failure to set a
>>> -# breakpoint (matched by re_cannot_insert_bp) and a stop in longjmp.
>>> -#
>>> -# We detect the different failure modes and kfail these.
>>> +    if {![runto_main]} {
>>> +    return 0
>>> +    }
>>> -set have_longjmp_probe 0
>>> -gdb_test_multiple "info probes stap libc ^longjmp$" "" {
>>> -    -re -wrap "No probes matched\\." {
>>> -    pass $gdb_test_name
>>> +    # With a libc with probes, all tests should pass.
>>> +    #
>>> +    # Without probes, we can still set a break on longjmp, but getting the longjmp
>>> +    # target may not work, in the following cases:
>>> +    # - gdbarch_get_longjmp_target_p (gdbarch) == 0: not implemented.
>>> +    # - gdbarch_get_longjmp_target (gdbarch) == 0: for instance on amd64 if
>>> +    #   tdep->jb_pc_offset == -1.
>>> +    # - gdbarch_get_longjmp_target (gdbarch) != 0: if we have a glibc with
>>> +    #   pointer mangling ( https://sourceware.org/glibc/wiki/PointerEncryption )
>>> +    #   then we retrieve a mangled longjmp target that needs to be demangled.
>>> +    #   For instance on amd64 with target board unix/-m32.
>>> +    #
>>> +    # Pointer demangling is currently not implemented for any target.
>>> +    # For the amd64 case, this would require copying for instance this:
>>> +    #   48 c1 ca 11             ror    $0x11,%rdx
>>> +    #   64 48 33 14 25 30 00    xor    %fs:0x30,%rdx
>>> +    # into a scratch space, save the register set, set %rdx to the mangled
>>> +    # longjmp target, displaced-step through the two insn and read the
>>> +    # demangled longjmp target from %rdx, and restore the register set.
>>> +    #
>>> +    # The failure mode in the first two cases is that the next degrades into a
>>> +    # continue.  The failure mode in the latter case is a failure to set a
>>> +    # breakpoint (matched by re_cannot_insert_bp) and a stop in longjmp.
>>> +    #
>>> +    # We detect the different failure modes and kfail these.
>>> +
>>> +    set have_longjmp_probe 0
>>> +    gdb_test_multiple "info probes stap libc ^longjmp$" "" {
>>> +    -re -wrap "No probes matched\\." {
>>> +        pass $gdb_test_name
>>> +    }
>>> +    -re -wrap "\r\nstap\[ \t\]+libc\[ \t\]+longjmp\[ \t\]+.*" {
>>> +        pass $gdb_test_name
>>> +        set have_longjmp_probe 1
>>> +    }
>>>       }
>>> -    -re -wrap "\r\nstap\[ \t\]+libc\[ \t\]+longjmp\[ \t\]+.*" {
>>> -    pass $gdb_test_name
>>> -    set have_longjmp_probe 1
>>> +
>>> +    if { $with_probes } {
>>> +    if { !$have_longjmp_probe } {
>>> +        unsupported "longjmp probe required"
>>> +        return
>>> +    }
>>> +    } else {
>>> +    gdb_assert { !$have_longjmp_probe }
>>>       }
>>> -}
>>> -set bp_miss_step_1 [gdb_get_line_number "miss_step_1"]
>>> -set bp_miss_step_2 [gdb_get_line_number "miss_step_2"]
>>> +    set bp_miss_step_1 [gdb_get_line_number "miss_step_1"]
>>> +    set bp_miss_step_2 [gdb_get_line_number "miss_step_2"]
>>> -set bp_start_test_1 [gdb_get_line_number "patt1"]
>>> -set bp_start_test_2 [gdb_get_line_number "patt2"]
>>> -set bp_start_test_3 [gdb_get_line_number "patt3"]
>>> +    set bp_start_test_1 [gdb_get_line_number "patt1"]
>>> +    set bp_start_test_2 [gdb_get_line_number "patt2"]
>>> +    set bp_start_test_3 [gdb_get_line_number "patt3"]
>>> -set re_cannot_insert_bp \
>>> -    [multi_line \
>>> -     "Warning:" \
>>> -     "Cannot insert breakpoint $decimal\\." \
>>> -     "Cannot access memory at address $hex"]
>>> +    set re_cannot_insert_bp \
>>> +    [multi_line \
>>> +         "Warning:" \
>>> +         "Cannot insert breakpoint $::decimal\\." \
>>> +         "Cannot access memory at address $::hex"]
>>> -#
>>> -# Pattern 1 - simple longjmp.
>>> -#
>>> +    #
>>> +    # Pattern 1 - simple longjmp.
>>> +    #
>>> -with_test_prefix "pattern 1" {
>>> +    with_test_prefix "pattern 1" {
>>> -    with_test_prefix setup {
>>> -    delete_breakpoints
>>> +    with_test_prefix setup {
>>> +        delete_breakpoints
>>> -    gdb_test "break $bp_start_test_1" \
>>> -        "Breakpoint.*at.* file .*$srcfile, line.*$bp_start_test_1.*" \
>>> -        "breakpoint at pattern start"
>>> -    gdb_test "continue" "patt1.*" "continue to breakpoint at pattern start"
>>> +        gdb_test "break $bp_start_test_1" \
>>> +        "Breakpoint.*at.* file .*$::srcfile, line.*$bp_start_test_1.*" \
>>> +        "breakpoint at pattern start"
>>> +        gdb_test "continue" "patt1.*" "continue to breakpoint at pattern start"
>>> -    # set safe-net break
>>> -    gdb_test "break $bp_miss_step_1" \
>>> -        "Breakpoint.*at.* file .*$srcfile, line.*$bp_miss_step_1.*" \
>>> -        "breakpoint at safety net"
>>> -    }
>>> +        # set safe-net break
>>> +        gdb_test "break $bp_miss_step_1" \
>>> +        "Breakpoint.*at.* file .*$::srcfile, line.*$bp_miss_step_1.*" \
>>> +        "breakpoint at safety net"
>>> +    }
>>> -    gdb_test "next" "longjmps\\+\\+;.*" "next over setjmp"
>>> -    gdb_test "next" "longjmp \\(env, 1\\);.*" "next to longjmp"
>>> +    gdb_test "next" "longjmps\\+\\+;.*" "next over setjmp"
>>> +    gdb_test "next" "longjmp \\(env, 1\\);.*" "next to longjmp"
>>> -    set msg "next over longjmp"
>>> -    gdb_test_multiple "next" $msg {
>>> -    -re ".*patt1.*$gdb_prompt $" {
>>> -        pass $msg
>>> -        gdb_test "next" "resumes\\+\\+.*" "next into else block"
>>> -        gdb_test "next" "miss_step_1.*" "next into safety net"
>>> -    }
>>> -    -re "miss_step_1.*$gdb_prompt $" {
>>> -        if { $have_longjmp_probe } {
>>> -        fail $gdb_test_name
>>> -        } else {
>>> -        kfail $gdb_test_name "gdb/26967"
>>> +    set msg "next over longjmp"
>>> +    gdb_test_multiple "next" $msg {
>>> +        -re ".*patt1.*$::gdb_prompt $" {
>>> +        pass $msg
>>> +        gdb_test "next" "resumes\\+\\+.*" "next into else block"
>>> +        gdb_test "next" "miss_step_1.*" "next into safety net"
>>>           }
>>> -    }
>>> -    -re -wrap "\r\n$re_cannot_insert_bp\r\n.*" {
>>> -        if { $have_longjmp_probe } {
>>> -        fail $gdb_test_name
>>> -        } else {
>>> -        kfail $gdb_test_name "gdb/26967"
>>> +        -re "miss_step_1.*$::gdb_prompt $" {
>>> +        if { $have_longjmp_probe } {
>>> +            fail $gdb_test_name
>>> +        } else {
>>> +            kfail $gdb_test_name "gdb/26967"
>>> +        }
>>> +        }
>>> +        -re -wrap "\r\n$re_cannot_insert_bp\r\n.*" {
>>> +        if { $have_longjmp_probe } {
>>> +            fail $gdb_test_name
>>> +        } else {
>>> +            kfail $gdb_test_name "gdb/26967"
>>> +        }
>>>           }
>>>       }
>>>       }
>>> -}
>>> -#
>>> -# Pattern 2 - longjmp from an inner function.
>>> -#
>>> +    #
>>> +    # Pattern 2 - longjmp from an inner function.
>>> +    #
>>> -with_test_prefix "pattern 2" {
>>> +    with_test_prefix "pattern 2" {
>>> -    with_test_prefix setup {
>>> -    delete_breakpoints
>>> +    with_test_prefix setup {
>>> +        delete_breakpoints
>>> -    gdb_test "break $bp_start_test_2" \
>>> -        "Breakpoint.*at.* file .*$srcfile, line.*$bp_start_test_2.*" \
>>> -        "breakpoint at pattern start"
>>> -    gdb_test "continue" "patt2.*" "continue to breakpoint at pattern start"
>>> +        gdb_test "break $bp_start_test_2" \
>>> +        "Breakpoint.*at.* file .*$::srcfile, line.*$bp_start_test_2.*" \
>>> +        "breakpoint at pattern start"
>>> +        gdb_test "continue" "patt2.*" "continue to breakpoint at pattern start"
>>> -    # set safe-net break
>>> -    gdb_test "break $bp_miss_step_2" \
>>> -        "Breakpoint.*at.* file .*$srcfile, line.*$bp_miss_step_2.*" \
>>> -        "breakpoint at safety net"
>>> -    }
>>> +        # set safe-net break
>>> +        gdb_test "break $bp_miss_step_2" \
>>> +        "Breakpoint.*at.* file .*$::srcfile, line.*$bp_miss_step_2.*" \
>>> +        "breakpoint at safety net"
>>> +    }
>>> -    gdb_test "next" "call_longjmp.*" "next over setjmp"
>>> +    gdb_test "next" "call_longjmp.*" "next over setjmp"
>>> -    set msg "next over call_longjmp"
>>> -    gdb_test_multiple "next" $msg {
>>> -    -re ".*patt2.*$gdb_prompt $" {
>>> -        pass $msg
>>> +    set msg "next over call_longjmp"
>>> +    gdb_test_multiple "next" $msg {
>>> +        -re ".*patt2.*$::gdb_prompt $" {
>>> +        pass $msg
>>> -        gdb_test "next" "resumes\\+\\+.*" "next into else block"
>>> -        gdb_test "next" "miss_step_2.*" "next into safety net"
>>> -    }
>>> -    -re "miss_step_2.*$gdb_prompt $" {
>>> -        if { $have_longjmp_probe } {
>>> -        fail $gdb_test_name
>>> -        } else {
>>> -        kfail $gdb_test_name "gdb/26967"
>>> +        gdb_test "next" "resumes\\+\\+.*" "next into else block"
>>> +        gdb_test "next" "miss_step_2.*" "next into safety net"
>>>           }
>>> -    }
>>> -    -re -wrap "\r\n$re_cannot_insert_bp\r\n.*" {
>>> -        if { $have_longjmp_probe } {
>>> -        fail $gdb_test_name
>>> -        } else {
>>> -        kfail $gdb_test_name "gdb/26967"
>>> +        -re "miss_step_2.*$::gdb_prompt $" {
>>> +        if { $have_longjmp_probe } {
>>> +            fail $gdb_test_name
>>> +        } else {
>>> +            kfail $gdb_test_name "gdb/26967"
>>> +        }
>>> +        }
>>> +        -re -wrap "\r\n$re_cannot_insert_bp\r\n.*" {
>>> +        if { $have_longjmp_probe } {
>>> +            fail $gdb_test_name
>>> +        } else {
>>> +            kfail $gdb_test_name "gdb/26967"
>>> +        }
>>>           }
>>>       }
>>>       }
>>> -}
>>> -#
>>> -# Pattern 3 - setjmp/longjmp inside stepped-over function.
>>> -#
>>> +    #
>>> +    # Pattern 3 - setjmp/longjmp inside stepped-over function.
>>> +    #
>>> -with_test_prefix "pattern 3" {
>>> +    with_test_prefix "pattern 3" {
>>> -    with_test_prefix setup {
>>> -    delete_breakpoints
>>> +    with_test_prefix setup {
>>> +        delete_breakpoints
>>> -    gdb_test "break $bp_start_test_3" \
>>> -        "Breakpoint.*at.* file .*$srcfile, line.*$bp_start_test_3.*" \
>>> -        "breakpoint at pattern start"
>>> -    gdb_test "continue" "patt3.*" "continue to breakpoint at pattern start"
>>> -    }
>>> -
>>> -    gdb_test_multiple "next" "next over pattern" {
>>> -    -re -wrap "longjmp caught.*" {
>>> -        pass $gdb_test_name
>>> +        gdb_test "break $bp_start_test_3" \
>>> +        "Breakpoint.*at.* file .*$::srcfile, line.*$bp_start_test_3.*" \
>>> +        "breakpoint at pattern start"
>>> +        gdb_test "continue" "patt3.*" "continue to breakpoint at pattern start"
>>>       }
>>> -    -re -wrap "\r\n$re_cannot_insert_bp\r\n.*" {
>>> -        if { $have_longjmp_probe } {
>>> -        fail $gdb_test_name
>>> -        } else {
>>> -        kfail $gdb_test_name "gdb/26967"
>>> +
>>> +    gdb_test_multiple "next" "next over pattern" {
>>> +        -re -wrap "longjmp caught.*" {
>>> +        pass $gdb_test_name
>>> +        }
>>> +        -re -wrap "\r\n$re_cannot_insert_bp\r\n.*" {
>>> +        if { $have_longjmp_probe } {
>>> +            fail $gdb_test_name
>>> +        } else {
>>> +            kfail $gdb_test_name "gdb/26967"
>>> +        }
>>>           }
>>>       }
>>>       }
>>>   }
>>> +
>>> +foreach_with_prefix with_probes { 0 1 } {
>>> +    do_test $with_probes
>>> +}
>>>
>>> base-commit: 0ab9328277ce12014ce05ff139eba7a6230516fd
>>
>