Public bug reported:
There seems to be a regression in QEMU 2.1.0 which demonstrates itself
when running the attached HelenOS Integrator/CP (i.e. ARMv5) image. The
offending instruction seems to be:
vmrs r0, fpsid
Upon its execution, HelenOS kernel receives an Undefined instruction
exception (which it does not anticipate at that point) and crashes.
QEMU 2.0.0 was not affected by this issue.
Command line to reproduce with QEMU 2.1.0:
$ qemu-system-arm -M integratorcp -kernel image.boot -s -S &
$ /usr/local/cross/arm32/bin/arm-linux-gnueabi-gdb
...
(gdb) target remote localhost:1234
Remote debugging using localhost:1234
warning: Can not parse XML target description; XML support was disabled at
compile time
0x00000000 in ?? ()
(gdb) symbol-file kernel/kernel.raw
Reading symbols from
/home/jermar/software/HelenOS.mainline/kernel/kernel.raw...done.
(gdb) break ras_check
Breakpoint 1 at 0x80a021bc: file arch/arm32/src/ras.c, line 67.
(gdb) c
Continuing.
Breakpoint 1, ras_check (n=1, istate=0x813e7f70) at arch/arm32/src/ras.c:67
67 {
(gdb) set radix 16
Input and output radices now set to decimal 16, hex 10, octal 20.
(gdb) print istate->pc
$1 = 0x80a02458
(gdb) disassemble 0x80a02458
Dump of assembler code for function fpsid_read:
0x80a02454 <+0>: vmrs r0, fpsid <=======
UNDEFINED EXCEPTION INSTRUCTION
0x80a02458 <+4>: mov pc, lr
End of assembler dump.
The Undefined instruction exception is not expected at this point when
executing the VMRS r0,fpsid instruction.
** Affects: helenos
Importance: Undecided
Status: New
** Affects: qemu
Importance: Undecided
Status: New
** Tags: 2.1.0 arm helenos integratorcp
** Attachment added: "HelenOS/arm32/integratorcp image"
https://bugs.launchpad.net/bugs/1359930/+attachment/4183965/+files/image.boot
** Also affects: helenos
Importance: Undecided
Status: New
--
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1359930
Title:
[ARMv5] Integrator/CP regression when reading FPSID instruction
Status in Home for various HelenOS development branches:
New
Status in QEMU:
New
Bug description:
There seems to be a regression in QEMU 2.1.0 which demonstrates itself
when running the attached HelenOS Integrator/CP (i.e. ARMv5) image. The
offending instruction seems to be:
vmrs r0, fpsid
Upon its execution, HelenOS kernel receives an Undefined instruction
exception (which it does not anticipate at that point) and crashes.
QEMU 2.0.0 was not affected by this issue.
Command line to reproduce with QEMU 2.1.0:
$ qemu-system-arm -M integratorcp -kernel image.boot -s -S &
$ /usr/local/cross/arm32/bin/arm-linux-gnueabi-gdb
...
(gdb) target remote localhost:1234
Remote debugging using localhost:1234
warning: Can not parse XML target description; XML support was disabled at
compile time
0x00000000 in ?? ()
(gdb) symbol-file kernel/kernel.raw
Reading symbols from
/home/jermar/software/HelenOS.mainline/kernel/kernel.raw...done.
(gdb) break ras_check
Breakpoint 1 at 0x80a021bc: file arch/arm32/src/ras.c, line 67.
(gdb) c
Continuing.
Breakpoint 1, ras_check (n=1, istate=0x813e7f70) at arch/arm32/src/ras.c:67
67 {
(gdb) set radix 16
Input and output radices now set to decimal 16, hex 10, octal 20.
(gdb) print istate->pc
$1 = 0x80a02458
(gdb) disassemble 0x80a02458
Dump of assembler code for function fpsid_read:
0x80a02454 <+0>: vmrs r0, fpsid <=======
UNDEFINED EXCEPTION INSTRUCTION
0x80a02458 <+4>: mov pc, lr
End of assembler dump.
The Undefined instruction exception is not expected at this point when
executing the VMRS r0,fpsid instruction.
To manage notifications about this bug go to:
https://bugs.launchpad.net/helenos/+bug/1359930/+subscriptions
