qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: Andrew Jones <drjones@redhat.com>
Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org
Subject: Re: [Qemu-devel] [PATCH] kvm-all: PAGE_SIZE should be real host page size
Date: Tue, 10 Nov 2015 17:15:43 +0100	[thread overview]
Message-ID: <5642182F.8020108@redhat.com> (raw)
In-Reply-To: <20151110155728.GB3452@hawk.localdomain>



On 10/11/2015 16:57, Andrew Jones wrote:
> On Tue, Nov 10, 2015 at 04:41:16PM +0100, Paolo Bonzini wrote:
>>
>>
>> On 10/11/2015 01:23, Andrew Jones wrote:
>>> Just noticed this while grepping TARGET_PAGE_SIZE for an unrelated
>>> reason. I didn't use qemu_real_host_page_size as kvm_set_phys_mem()
>>> does, because we'd need to make sure page_size_init() has run first.
>>>
>>> Signed-off-by: Andrew Jones <drjones@redhat.com>
>>> ---
>>>  kvm-all.c | 6 ++++--
>>>  1 file changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/kvm-all.c b/kvm-all.c
>>> index 1bc12737723c3..de9ff5971fb3b 100644
>>> --- a/kvm-all.c
>>> +++ b/kvm-all.c
>>> @@ -45,8 +45,10 @@
>>>  #include <sys/eventfd.h>
>>>  #endif
>>>  
>>> -/* KVM uses PAGE_SIZE in its definition of COALESCED_MMIO_MAX */
>>> -#define PAGE_SIZE TARGET_PAGE_SIZE
>>> +/* KVM uses PAGE_SIZE in its definition of KVM_COALESCED_MMIO_MAX. We
>>> + * need to use the real host PAGE_SIZE, as that's what KVM will use.
>>> + */
>>> +#define PAGE_SIZE getpagesize()
>>>  
>>>  //#define DEBUG_KVM
>>>  
>>>
>>
>> Is this a bugfix or just a cleanup?  If the former, on which targets?
> 
> It's a bugfix for any targets that have a TARGET_PAGE_SIZE !=
> real-host-page-size. For example ARM has TARGET_PAGE_SIZE set to 1024,
> even when the host is using 4k or 64k pages. However, I didn't find this
> due to a bug, because on ARM I'm not using emulated devices that make
> use of the coalesced-mmio feature at this time.
> 
> Thanks,
> drew
> 
>>
>> Paolo
>> --
>> To unsubscribe from this list: send the line "unsubscribe kvm" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Ok, applied (2.6 only unless I gather more urgent patches).

Paolo

  reply	other threads:[~2015-11-10 16:15 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-10  0:23 [Qemu-devel] [PATCH] kvm-all: PAGE_SIZE should be real host page size Andrew Jones
2015-11-10 15:41 ` Paolo Bonzini
2015-11-10 15:57   ` Andrew Jones
2015-11-10 16:15     ` Paolo Bonzini [this message]
2015-11-10 16:29 ` Peter Maydell
2015-11-10 16:59   ` Andrew Jones
2015-11-10 17:02     ` Peter Maydell

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=5642182F.8020108@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=drjones@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=qemu-devel@nongnu.org \
    /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).