Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1736826

Re: [Xen-devel] [PATCH] xen: support 52 bit physical addresses in pv guests

From Andrew Cooper <andrew.cooper3@citrix.com>
Newsgroups linux.kernel
Subject Re: [Xen-devel] [PATCH] xen: support 52 bit physical addresses in pv guests
Date 2017-09-21 18:20 +0200
Message-ID <uscmK-3iX-23@gated-at.bofh.it> (permalink)
References <us4Iy-6IJ-11@gated-at.bofh.it> <usauC-25s-17@gated-at.bofh.it> <usaXD-2gx-9@gated-at.bofh.it> <uscd3-3f6-9@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On 21/09/17 17:00, Boris Ostrovsky wrote:
>
>>
>>>
>>>>
>>>> Signed-off-by: Juergen Gross <jgross@suse.com>
>>>> ---
>>>>    arch/x86/include/asm/xen/page.h | 11 ++++++++++-
>>>>    arch/x86/xen/mmu_pv.c           |  4 ++--
>>>>    2 files changed, 12 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/arch/x86/include/asm/xen/page.h
>>>> b/arch/x86/include/asm/xen/page.h
>>>> index 07b6531813c4..bcb8b193c8d1 100644
>>>> --- a/arch/x86/include/asm/xen/page.h
>>>> +++ b/arch/x86/include/asm/xen/page.h
>>>> @@ -26,6 +26,15 @@ typedef struct xpaddr {
>>>>        phys_addr_t paddr;
>>>>    } xpaddr_t;
>>>>    +#ifdef CONFIG_X86_64
>>>> +#define XEN_PHYSICAL_MASK    ((1UL << 52) - 1)
>>>
>>>
>>> SME is not supported for PV guests but for consistency (and in case sme
>>> bit somehow gets set)
>>> #define XEN_PHYSICAL_MASK    __sme_clr(((1UL << 52) - 1))
>>
>> Hmm, really? Shouldn't we rather add something like
>>
>> BUG_ON(sme_active());
>>
>> somewhere?
>
> We can do that too.

Please don't do anything to cause Linux to crash if Xen is using SME 
itself, but leaving all of the PV guest unencrypted.

~Andrew

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH] xen: support 52 bit physical addresses in pv guests Juergen Gross <jgross@suse.com> - 2017-09-21 10:10 +0200
  Re: [PATCH] xen: support 52 bit physical addresses in pv guests Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-09-21 16:20 +0200
    Re: [PATCH] xen: support 52 bit physical addresses in pv guests Juergen Gross <jgross@suse.com> - 2017-09-21 16:50 +0200
      Re: [PATCH] xen: support 52 bit physical addresses in pv guests Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-09-21 18:10 +0200
        Re: [Xen-devel] [PATCH] xen: support 52 bit physical addresses in pv  guests Andrew Cooper <andrew.cooper3@citrix.com> - 2017-09-21 18:20 +0200
          Re: [Xen-devel] [PATCH] xen: support 52 bit physical addresses in pv  guests Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2017-09-21 21:10 +0200

csiph-web