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From: Paolo Bonzini <pbonzini@redhat.com>
To: Scott Wood <scottwood@freescale.com>
Cc: Peter Maydell <peter.maydell@linaro.org>,
	"Bogdan.Vlad@freescale.com" <Bogdan.Vlad@freescale.com>,
	Alexander Graf <agraf@suse.de>,
	QEMU Developers <qemu-devel@nongnu.org>,
	Marc Zyngier <marc.zyngier@arm.com>,
	"qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>,
	"mihai.caraman@freescale.com" <mihai.caraman@freescale.com>,
	"Varun.Sethi@freescale.com" <Varun.Sethi@freescale.com>
Subject: Re: [Qemu-devel] [PATCH] roms: Flush icache when writing roms to guest memory
Date: Sat, 14 Dec 2013 11:58:58 +0100	[thread overview]
Message-ID: <52AC39F2.4010104@redhat.com> (raw)
In-Reply-To: <1386962330.10013.302.camel@snotra.buserror.net>

Il 13/12/2013 20:18, Scott Wood ha scritto:
>> Also are you sure flush_icache_range()
>> works correctly when multiple threads (multiple vCPUs,
>> potentially executing on different host CPUs) are involved?
> 
> On PPC these cache operations broadcast, and are the architecturally
> defined way of doing self-modifying code.

I expect that to be the same on any cache-coherent system.

On a VIVT cache with shadow paging, some kernel collaboration may be
necessary because you have to flush using guest addresses rather than
host addresses (or alternatively you have to flush a whole context id).
 But we can fix the problem when it happens.

Paolo

  reply	other threads:[~2013-12-14 10:59 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-11 13:23 [Qemu-devel] [PATCH] roms: Flush icache when writing roms to guest memory Alexander Graf
2013-12-11 13:27 ` Paolo Bonzini
2013-12-11 13:35   ` Alexander Graf
2013-12-11 14:03     ` Paolo Bonzini
2013-12-11 14:20       ` Alexander Graf
2013-12-11 14:07     ` Peter Maydell
2013-12-11 14:17       ` Alexander Graf
2013-12-11 14:27         ` mihai.caraman
2013-12-11 14:18       ` mihai.caraman
2013-12-11 14:25         ` Peter Maydell
2013-12-11 14:31           ` Alexander Graf
2013-12-11 14:58           ` mihai.caraman
2013-12-11 13:56 ` Peter Maydell
2013-12-13 19:18   ` Scott Wood
2013-12-14 10:58     ` Paolo Bonzini [this message]
2013-12-14 11:08       ` Peter Maydell

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