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Message-ID: <1192d7c0bafcfe47c1822afe09c25fda0a42a012.camel@infradead.org>
Subject: Re: [PATCH v13 21/21] KVM: pfncache: rework __kvm_gpc_refresh() to
 fix locking issues
From: David Woodhouse <dwmw2@infradead.org>
To: Sean Christopherson <seanjc@google.com>, paul@xen.org
Cc: Paolo Bonzini <pbonzini@redhat.com>, Jonathan Corbet <corbet@lwn.net>, 
 Christian Borntraeger <borntraeger@linux.ibm.com>, Janosch Frank
 <frankja@linux.ibm.com>, Claudio Imbrenda <imbrenda@linux.ibm.com>, David
 Hildenbrand <david@redhat.com>, Heiko Carstens <hca@linux.ibm.com>, Vasily
 Gorbik <gor@linux.ibm.com>, Alexander Gordeev <agordeev@linux.ibm.com>,
 Sven Schnelle <svens@linux.ibm.com>, Thomas Gleixner <tglx@linutronix.de>,
 Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, Dave Hansen
 <dave.hansen@linux.intel.com>, x86@kernel.org, "H. Peter Anvin"
 <hpa@zytor.com>, Shuah Khan <shuah@kernel.org>, kvm@vger.kernel.org, 
 linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, 
 linux-s390@vger.kernel.org, linux-kselftest@vger.kernel.org
Date: Sat, 17 Feb 2024 10:52:49 +0000
In-Reply-To: <Zc-EwMoijOo7w49N@google.com>
References: <20240215152916.1158-1-paul@xen.org>
	 <20240215152916.1158-22-paul@xen.org>
	 <23e7ec31a67a73fe94b2b04dbca26ea5ca1ea238.camel@infradead.org>
	 <df6ad8b9-4e53-4357-ab17-e9af62342849@xen.org>
	 <Zc-EwMoijOo7w49N@google.com>
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On Fri, 2024-02-16 at 07:52 -0800, Sean Christopherson wrote:
>=20
> FWIW, I'm not opposed to overhauling the gpc locking, I agree it's a mess=
=C2=A0 I just
> want to proceed slower than I would for a fix, it's a lot to digest.

Agreed. I'll do a *really* simple expansion of ->refresh_lock for the fix, =
and
then cleaning up the rwlock abuse can come later (at the very end of
the series I'm about to post, so it can be ignored for now).

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