From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "tiejun.chen" <tiejun.chen@windriver.com>
Cc: Alexander Graf <agraf@suse.de>,
"<kvm-ppc@vger.kernel.org>" <kvm-ppc@vger.kernel.org>,
"<kvm@vger.kernel.org> list" <kvm@vger.kernel.org>
Subject: Re: [v1][PATCH 1/1] KVM: PPC: disable preemption when using hard_irq_disable()
Date: Fri, 12 Jul 2013 03:57:40 +0000 [thread overview]
Message-ID: <1373601460.19894.135.camel@pasglop> (raw)
In-Reply-To: <51DF6653.7010902@windriver.com>
On Fri, 2013-07-12 at 10:13 +0800, tiejun.chen wrote:
> > #define hard_irq_disable() do { \
> > u8 _was_enabled = get_paca()->soft_enabled; \
>
> Current problem I met is issued from the above line.
>
> > __hard_irq_disable(); \
> > - get_paca()->soft_enabled = 0; \
>
> Not here.
>
> If I'm misunderstanding what you guys means, please correct me since this is a
> long discussion thread. I have to reread that carefully.
Then make it
u8 _was_enabled;
__hard_irq_disable();
was_enabled = local_paca->....
Once you have hard disabled, using local_paca directly *should* be safe
(minus that gcc problem I mentioned).
Cheers,
Ben.
WARNING: multiple messages have this Message-ID (diff)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "tiejun.chen" <tiejun.chen@windriver.com>
Cc: Alexander Graf <agraf@suse.de>,
"<kvm-ppc@vger.kernel.org>" <kvm-ppc@vger.kernel.org>,
"<kvm@vger.kernel.org> list" <kvm@vger.kernel.org>
Subject: Re: [v1][PATCH 1/1] KVM: PPC: disable preemption when using hard_irq_disable()
Date: Fri, 12 Jul 2013 13:57:40 +1000 [thread overview]
Message-ID: <1373601460.19894.135.camel@pasglop> (raw)
In-Reply-To: <51DF6653.7010902@windriver.com>
On Fri, 2013-07-12 at 10:13 +0800, tiejun.chen wrote:
> > #define hard_irq_disable() do { \
> > u8 _was_enabled = get_paca()->soft_enabled; \
>
> Current problem I met is issued from the above line.
>
> > __hard_irq_disable(); \
> > - get_paca()->soft_enabled = 0; \
>
> Not here.
>
> If I'm misunderstanding what you guys means, please correct me since this is a
> long discussion thread. I have to reread that carefully.
Then make it
u8 _was_enabled;
__hard_irq_disable();
was_enabled = local_paca->....
Once you have hard disabled, using local_paca directly *should* be safe
(minus that gcc problem I mentioned).
Cheers,
Ben.
next prev parent reply other threads:[~2013-07-12 3:57 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-10 6:02 [v1][PATCH 1/1] KVM: PPC: disable preemption when using hard_irq_disable() Tiejun Chen
2013-07-10 6:02 ` Tiejun Chen
2013-07-10 9:49 ` Alexander Graf
2013-07-10 9:49 ` Alexander Graf
2013-07-11 2:48 ` tiejun.chen
2013-07-11 2:48 ` tiejun.chen
2013-07-11 9:49 ` Alexander Graf
2013-07-11 9:49 ` Alexander Graf
2013-07-11 12:28 ` Benjamin Herrenschmidt
2013-07-11 12:28 ` Benjamin Herrenschmidt
2013-07-11 12:47 ` Alexander Graf
2013-07-11 12:47 ` Alexander Graf
2013-07-11 12:54 ` Benjamin Herrenschmidt
2013-07-11 12:54 ` Benjamin Herrenschmidt
2013-07-11 13:07 ` Alexander Graf
2013-07-11 13:07 ` Alexander Graf
2013-07-12 0:19 ` Benjamin Herrenschmidt
2013-07-12 0:19 ` Benjamin Herrenschmidt
2013-07-12 2:13 ` tiejun.chen
2013-07-12 2:13 ` tiejun.chen
2013-07-12 3:57 ` Benjamin Herrenschmidt [this message]
2013-07-12 3:57 ` Benjamin Herrenschmidt
2013-07-12 4:54 ` tiejun.chen
2013-07-12 4:54 ` tiejun.chen
2013-07-14 4:13 ` Benjamin Herrenschmidt
2013-07-14 4:13 ` Benjamin Herrenschmidt
2013-07-15 3:04 ` tiejun.chen
2013-07-15 3:04 ` tiejun.chen
2013-07-10 19:15 ` Scott Wood
2013-07-10 19:15 ` Scott Wood
2013-07-10 19:15 ` Scott Wood
2013-07-11 2:59 ` tiejun.chen
2013-07-11 3:00 ` tiejun.chen
2013-07-11 3:00 ` tiejun.chen
2013-07-11 14:13 ` Scott Wood
2013-07-11 14:13 ` Scott Wood
[not found] <1373559480.8183.258@snotra>
2013-07-12 0:30 ` Benjamin Herrenschmidt
2013-07-12 0:30 ` Benjamin Herrenschmidt
[not found] ` <FB21594A-C233-4A97-8503-E2A1275F8F17@suse.de>
[not found] ` <1373560585.8183.261@snotra>
2013-07-12 3:22 ` tiejun.chen
2013-07-12 3:22 ` tiejun.chen
[not found] <1373651433.8183.276@snotra>
2013-07-12 23:05 ` Benjamin Herrenschmidt
2013-07-12 23:05 ` Benjamin Herrenschmidt
2013-07-15 2:20 ` tiejun.chen
2013-07-15 2:20 ` tiejun.chen
2013-07-15 2:47 ` Benjamin Herrenschmidt
2013-07-15 2:47 ` Benjamin Herrenschmidt
2013-07-15 3:03 ` tiejun.chen
2013-07-15 3:03 ` tiejun.chen
[not found] ` <1373909248.8183.303@snotra>
2013-07-16 2:15 ` tiejun.chen
2013-07-16 2:15 ` tiejun.chen
2013-07-15 2:25 ` tiejun.chen
2013-07-15 2:25 ` tiejun.chen
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