From: Ralf Baechle <ralf@linux-mips.org>
To: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org, kvm@vger.kernel.org,
Sanjay Lal <sanjayl@kymasys.com>,
linux-kernel@vger.kernel.org,
David Daney <ddaney@caviumnetworks.com>
Subject: Re: [PATCH 01/31] MIPS: Move allocate_kscratch to cpu-probe.c and make it public.
Date: Fri, 14 Jun 2013 15:11:33 +0200 [thread overview]
Message-ID: <20130614131133.GA21005@linux-mips.org> (raw)
In-Reply-To: <20130614114118.GD15775@linux-mips.org>
On Fri, Jun 14, 2013 at 01:41:18PM +0200, Ralf Baechle wrote:
> Date: Fri, 14 Jun 2013 13:41:18 +0200
> From: Ralf Baechle <ralf@linux-mips.org>
> To: James Hogan <james.hogan@imgtec.com>
> Cc: linux-mips@linux-mips.org, kvm@vger.kernel.org, Sanjay Lal
> <sanjayl@kymasys.com>, linux-kernel@vger.kernel.org, David Daney
> <ddaney@caviumnetworks.com>
> Subject: Re: [PATCH 01/31] MIPS: Move allocate_kscratch to cpu-probe.c and
> make it public.
> Content-Type: text/plain; charset=us-ascii
>
> On Fri, Jun 07, 2013 at 04:03:05PM -0700, David Daney wrote:
> > Date: Fri, 7 Jun 2013 16:03:05 -0700
> > From: David Daney <ddaney.cavm@gmail.com>
> > To: linux-mips@linux-mips.org, ralf@linux-mips.org, kvm@vger.kernel.org,
> > Sanjay Lal <sanjayl@kymasys.com>
> > Cc: linux-kernel@vger.kernel.org, David Daney <ddaney@caviumnetworks.com>
> > Subject: [PATCH 01/31] MIPS: Move allocate_kscratch to cpu-probe.c and make
> > it public.
> >
> > From: David Daney <ddaney@caviumnetworks.com>
>
> I'd just like to add a note about compatibility. Code optimized for
> LL/SC-less CPUs has made use of the fact that exception handlers will
> clobber k0/k1 to a non-zero value. On a MIPS II or better CPU a branch
> likely instruction could be used to atomically test k0/k1 and depending
> on the test, execute a store instruction like:
>
> .set noreorder
> beqzl $k0, ok
> sw $reg, offset($reg)
> /* if we get here, our SC emulation has failed */
> ok: ...
>
> In particular Sony had elected to do this for the R5900 (after I explained
> the concept to somebody and told it'd be a _bad_ idea for compatibility
> reasons). Bad ideas are infectious so I'm sure others have used it, too.
>
> I don't think this should stop your patch nor should we unless this turns
> out to be an actual problem add any kludges to support such cowboy style
> hacks. But I wanted to mention and document the issue; maybe this should
> be mentioned in the log message of the next version of this patch.
>
> Acked-by: Ralf Baechle <ralf@linux-mips.org>
Bleh. I fatfingered mutt. This of course was the reply intended for
"[PATCH 02/31] MIPS: Save and restore K0/K1 when CONFIG_KVM_MIPSVZ".
As for 1/31:
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Ralf
next prev parent reply other threads:[~2013-06-14 13:11 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-07 23:03 [PATCH 00/31] KVM/MIPS: Implement hardware virtualization via the MIPS-VZ extensions David Daney
2013-06-07 23:03 ` [PATCH 01/31] MIPS: Move allocate_kscratch to cpu-probe.c and make it public David Daney
2013-06-14 11:41 ` Ralf Baechle
2013-06-14 13:11 ` Ralf Baechle [this message]
2013-06-07 23:03 ` [PATCH 02/31] MIPS: Save and restore K0/K1 when CONFIG_KVM_MIPSVZ David Daney
2013-06-07 23:03 ` [PATCH 03/31] mips/kvm: Fix 32-bitisms in kvm_locore.S David Daney
2013-06-14 13:09 ` Ralf Baechle
2013-06-14 13:21 ` Sergei Shtylyov
2013-06-07 23:03 ` [PATCH 04/31] mips/kvm: Add casts to avoid pointer width mismatch build failures David Daney
2013-06-14 13:14 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 05/31] mips/kvm: Use generic cache flushing functions David Daney
2013-06-14 13:17 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 06/31] mips/kvm: Rename kvm_vcpu_arch.pc to kvm_vcpu_arch.epc David Daney
2013-06-14 13:18 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 07/31] mips/kvm: Rename VCPU_registername to KVM_VCPU_ARCH_registername David Daney
2013-06-14 13:18 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 08/31] mips/kvm: Fix code formatting in arch/mips/kvm/kvm_locore.S David Daney
2013-06-14 13:21 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 09/31] mips/kvm: Factor trap-and-emulate support into a pluggable implementation David Daney
2013-06-14 13:22 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 10/31] mips/kvm: Implement ioctls to get and set FPU registers David Daney
2013-06-14 16:11 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 11/31] MIPS: Rearrange branch.c so it can be used by kvm code David Daney
2013-06-14 22:03 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 12/31] MIPS: Add instruction format information for WAIT, MTC0, MFC0, et al David Daney
2013-06-14 22:07 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 13/31] mips/kvm: Add accessors for MIPS VZ registers David Daney
2013-06-14 22:10 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 14/31] mips/kvm: Add thread_info flag to indicate operation in MIPS VZ Guest Mode David Daney
2013-06-14 22:10 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 15/31] mips/kvm: Exception handling to leave and reenter guest mode David Daney
2013-06-15 10:00 ` Ralf Baechle
2013-10-11 12:51 ` James Hogan
2013-06-07 23:03 ` [PATCH 16/31] mips/kvm: Add exception handler for MIPSVZ Guest exceptions David Daney
2013-06-15 10:23 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 17/31] MIPS: Quit exposing Kconfig symbols in uapi headers David Daney
2013-06-14 11:12 ` Ralf Baechle
2013-06-15 17:13 ` Paolo Bonzini
2013-06-07 23:03 ` [PATCH 18/31] mips/kvm: Add pt_regs slots for BadInstr and BadInstrP David Daney
2013-06-15 10:25 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 19/31] mips/kvm: Add host definitions for MIPS VZ based host David Daney
2013-06-16 8:49 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 20/31] mips/kvm: Hook into TLB fault handlers David Daney
2013-06-07 23:34 ` Sergei Shtylyov
2013-06-08 0:15 ` David Daney
2013-06-16 8:51 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 21/31] mips/kvm: Allow set_except_vector() to be used from MIPSVZ code David Daney
2013-06-16 11:22 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 22/31] mips/kvm: Split get_new_mmu_context into two parts David Daney
2013-06-16 11:26 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 23/31] mips/kvm: Hook into CP unusable exception handler David Daney
2013-06-16 11:28 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 24/31] mips/kvm: Add thread_struct fields used by MIPSVZ hosts David Daney
2013-06-16 11:29 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 25/31] mips/kvm: Add some asm-offsets constants used by MIPSVZ David Daney
2013-06-16 11:31 ` Ralf Baechle
2013-08-06 17:23 ` David Daney
2013-06-07 23:03 ` [PATCH 26/31] mips/kvm: Split up Kconfig and Makefile definitions in preperation for MIPSVZ David Daney
2013-06-16 11:33 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 27/31] mips/kvm: Gate the use of kvm_local_flush_tlb_all() by KVM_MIPSTE David Daney
2013-06-16 11:42 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 28/31] mips/kvm: Only use KVM_COALESCED_MMIO_PAGE_OFFSET with KVM_MIPSTE David Daney
2013-06-16 12:03 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 29/31] mips/kvm: Add MIPSVZ support David Daney
2013-06-16 11:47 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 30/31] mips/kvm: Enable MIPSVZ in Kconfig/Makefile David Daney
2013-06-16 11:44 ` Ralf Baechle
2013-06-07 23:03 ` [PATCH 31/31] mips/kvm: Allow for upto 8 KVM vcpus per vm David Daney
2013-06-16 11:37 ` Ralf Baechle
2013-06-07 23:15 ` [PATCH 00/31] KVM/MIPS: Implement hardware virtualization via the MIPS-VZ extensions David Daney
2013-06-09 7:31 ` Gleb Natapov
2013-06-09 23:23 ` David Daney
2013-06-09 23:40 ` Maciej W. Rozycki
2013-06-10 11:16 ` Ralf Baechle
2013-06-10 6:18 ` Gleb Natapov
2013-06-10 16:37 ` Sanjay Lal
2013-06-16 11:59 ` Ralf Baechle
2013-06-10 16:43 ` Sanjay Lal
2013-06-10 17:14 ` David Daney
2013-06-14 11:12 ` Ralf Baechle
2013-06-19 9:06 ` Ralf Baechle
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20130614131133.GA21005@linux-mips.org \
--to=ralf@linux-mips.org \
--cc=ddaney@caviumnetworks.com \
--cc=james.hogan@imgtec.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@linux-mips.org \
--cc=sanjayl@kymasys.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).