Le 23/08/2016 à 11:20, Alessio Igor Bogani a écrit :
Hi Christophe,
Sorry for delay in reply I was on vacation.
On 6 August 2016 at 11:29, christophe leroy <christophe.le...@c-s.fr> wrote:
Alessio,
Le 05/08/2016 à 09:51, Christophe Leroy a écrit :
Le 19/07/2016 à 23:52, Scott Wood a écrit :
On Tue, 2016-07-19 at 12:00 +0200, Alessio Igor Bogani wrote:
Hi all,
I have got two boards MVME5100 (MPC7410 cpu) and MVME7100 (MPC8641D
cpu) for which I use the same cross-compiler (ppc7400).
I tested these against kernel HEAD to found that these don't boot
anymore (PID 1 crash).
Bisecting results in first offending commit:
7aef4136566b0539a1a98391181e188905e33401
Removing it from HEAD make boards boot properly again.
A third system based on P2010 isn't affected at all.
Is it a regression or I have made something wrong?
I booted both my next branch, and Linus's master on MPC8641HPCN and
didn't see
this -- though possibly your RFS is doing something different. Maybe
that's
the difference with P2010 as well.
Is there any way you can debug the cause of the crash? Or send me a
minimal
RFS that demonstrates the problem (ideally with debug symbols on the
userspace
binaries)?
I got from Alessio the below information:
systemd[1]: Caught <BUS>, core dump failed (child 137, code=killed,
status=7/BUS).
systemd[1]: Freezing execution.
What can generate SIGBUS ?
And shouldn't we also get some KERN_ERR trace, something like "unhandled
signal 7 at ....." ?
As far as I can see, SIGBUS is mainly generated from alignment exception.
According to 7410 Reference Manual, alignment exception can happen in the
following cases:
* An operand of a dcbz instruction is on a page that is write-through or
cache-inhibited for a virtual mode access.
* An attempt to execute a dcbz instruction occurs when the cache is disabled
or locked.
Could try with below patch to check if the dcbz insn is causing the SIGBUS ?
Unfortunately that patch doesn't solve the problem.
Is there a chance that cache behavior could settled by board firmware
(PPCBug on the MPC7410 board and MotLoad on the MPC8641D one)?
In that case what do you suggest me to looking for?
If the removal of dcbz doesn't solve the issue, I don't think it is a
cache related issue.
As far as I understood, your init gets a SIGBUS signal, right ? Then we
must identify the reason for that sigbus.
Once it has happened, do you have access to 'dmesg' at all ?
If not, you should make sure the default log level on your console is
high enough to capture all messages, then I recommend you to send us
your complete console log from startup until init crash so that we can
get a complete picture.
Christophe
Christophe
diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S
index 68f6862..3ad782a 100644
--- a/arch/powerpc/lib/checksum_32.S
+++ b/arch/powerpc/lib/checksum_32.S
@@ -192,7 +192,7 @@ _GLOBAL(csum_partial_copy_generic)
mtctr r8
53: dcbt r3,r4
-54: dcbz r11,r6
+54: nop
/* the main body of the cacheline loop */
CSUM_COPY_16_BYTES_WITHEX(0)
#if L1_CACHE_BYTES >= 32
Thanks for your help!
Ciao,
Alessio
