RE: [RFC] Kprobes for book-e

Kumar Gala wrote Wednesday, June 11, 2008 8:36 PM

To: Sulibhavi, Madhvesh
Cc: rsmadhvesh@vsnl.net; ananth@in.ibm.com;=20
linuxppc-dev@ozlabs.org; Paul Mackerras
Subject: Re: [RFC] Kprobes for book-e
=20

...

---------------------------------------------------------------------

quoted

arch/powerpc/kernel/kprobes.c |   35 ++++++++++++++++++++++++++++++=20
+----
arch/powerpc/kernel/misc_32.S |    2 +-
arch/powerpc/kernel/traps.c   |   26 +++++++++++++++++++++++++-
3 files changed, 57 insertions(+), 6 deletions(-)

=20
Your patch got line wrapped by your mailer.  Take a look at =20
Documentation/email-clients.tx

Yes, i need to correct my emailer (long pending)

=20

quoted

static void __kprobes prepare_singlestep(struct kprobe *p, struct
pt_regs *regs)
{
+#ifdef CONFIG_BOOKE
+	regs->msr &=3D ~(MSR_EE); /* Turn off 'Externel Interrupt' bits */
+	regs->msr &=3D ~(MSR_CE); /* Turn off 'Critical Interrupt' bits */
+	regs->msr |=3D MSR_DE;

=20
can we remove MSR_EE and MSR_CE here?

Ah! yes? interrupts are enabled while executing the trap
instruction in ppc unlike int3 of x86 where interupts are=20
disabled. kprobe_handler already handles the reentrancy with=20
nmissed count. I think this code can be removed and=20
I will confirm after my test.


-Madhvesh


-------------------------------------------------------------------
This email is confidential and intended only for the use of the =
individual or entity named above and may contain information that is =
privileged. If you are not the intended recipient, you are notified that =
any dissemination, distribution or copying of this email is strictly =
prohibited. If you have received this email in error, please notify us =
immediately by return email or telephone and destroy the original =
message. - This mail is sent via Sony Asia Pacific Mail Gateway.
-------------------------------------------------------------------