Messages in this thread | | | Subject | Re: [RFC Part1 PATCH v3 07/17] x86/mm: Include SEV for encryption memory attribute changes | From | Tom Lendacky <> | Date | Thu, 17 Aug 2017 13:21:39 -0500 |
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On 7/28/2017 3:47 AM, David Laight wrote: > From: Borislav Petkov >> Sent: 27 July 2017 15:59 >> On Mon, Jul 24, 2017 at 02:07:47PM -0500, Brijesh Singh wrote: >>> From: Tom Lendacky <thomas.lendacky@amd.com> >>> >>> The current code checks only for sme_active() when determining whether >>> to perform the encryption attribute change. Include sev_active() in this >>> check so that memory attribute changes can occur under SME and SEV. >>> >>> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> >>> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> >>> --- >>> arch/x86/mm/pageattr.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c >>> index dfb7d65..b726b23 100644 >>> --- a/arch/x86/mm/pageattr.c >>> +++ b/arch/x86/mm/pageattr.c >>> @@ -1781,8 +1781,8 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc) >>> unsigned long start; >>> int ret; >>> >>> - /* Nothing to do if the SME is not active */ >>> - if (!sme_active()) >>> + /* Nothing to do if SME and SEV are not active */ >>> + if (!sme_active() && !sev_active()) >> >> This is the second place which does >> >> if (!SME && !SEV) >> >> I wonder if, instead of sprinking those, we should have a >> >> if (mem_enc_active()) >> >> or so which unifies all those memory encryption logic tests and makes >> the code more straightforward for readers who don't have to pay >> attention to SME vs SEV ... > > If any of the code paths are 'hot' it would make sense to be checking > a single memory location.
The function would check a single variable/memory location and making it an inline function would accomplish that.
Thanks, Tom
> > David >
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