From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Lendacky Subject: Re: [PATCH v5 26/32] x86, drm, fbdev: Do not specify encrypted memory for video mappings Date: Tue, 30 May 2017 15:07:05 -0500 Message-ID: <766ddfd1-d1fe-213f-1720-5e10356398f0@amd.com> References: <20170418211612.10190.82788.stgit@tlendack-t1.amdoffice.net> <20170418212056.10190.25468.stgit@tlendack-t1.amdoffice.net> <20170516173541.q2rbh5dhkluzsjae@pd.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170516173541.q2rbh5dhkluzsjae@pd.tnic> Content-Language: en-US Sender: owner-linux-mm@kvack.org To: Borislav Petkov Cc: linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Rik van Riel , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Toshimitsu Kani , Arnd Bergmann , Jonathan Corbet , Matt Fleming , "Michael S. Tsirkin" , Joerg Roedel , Konrad Rzeszutek Wilk , Paolo Bonzini , Larry Woodman , Brijesh Singh , Ingo Molnar , Andy Lutomirski , "H. Peter Anvin" , Andrey Ryabinin List-Id: linux-efi@vger.kernel.org On 5/16/2017 12:35 PM, Borislav Petkov wrote: > On Tue, Apr 18, 2017 at 04:20:56PM -0500, Tom Lendacky wrote: >> Since video memory needs to be accessed decrypted, be sure that the >> memory encryption mask is not set for the video ranges. >> >> Signed-off-by: Tom Lendacky >> --- >> arch/x86/include/asm/vga.h | 13 +++++++++++++ >> arch/x86/mm/pageattr.c | 2 ++ >> drivers/gpu/drm/drm_gem.c | 2 ++ >> drivers/gpu/drm/drm_vm.c | 4 ++++ >> drivers/gpu/drm/ttm/ttm_bo_vm.c | 7 +++++-- >> drivers/gpu/drm/udl/udl_fb.c | 4 ++++ >> drivers/video/fbdev/core/fbmem.c | 12 ++++++++++++ >> 7 files changed, 42 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/include/asm/vga.h b/arch/x86/include/asm/vga.h >> index c4b9dc2..5c7567a 100644 >> --- a/arch/x86/include/asm/vga.h >> +++ b/arch/x86/include/asm/vga.h >> @@ -7,12 +7,25 @@ >> #ifndef _ASM_X86_VGA_H >> #define _ASM_X86_VGA_H >> >> +#include >> + >> /* >> * On the PC, we can just recalculate addresses and then >> * access the videoram directly without any black magic. >> + * To support memory encryption however, we need to access >> + * the videoram as decrypted memory. >> */ >> >> +#ifdef CONFIG_AMD_MEM_ENCRYPT >> +#define VGA_MAP_MEM(x, s) \ >> +({ \ >> + unsigned long start = (unsigned long)phys_to_virt(x); \ >> + set_memory_decrypted(start, (s) >> PAGE_SHIFT); \ >> + start; \ >> +}) >> +#else >> #define VGA_MAP_MEM(x, s) (unsigned long)phys_to_virt(x) >> +#endif > > Can we push the check in and save us the ifdeffery? > > #define VGA_MAP_MEM(x, s) \ > ({ \ > unsigned long start = (unsigned long)phys_to_virt(x); \ > \ > if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) \ > set_memory_decrypted(start, (s) >> PAGE_SHIFT); \ > \ > start; \ > }) > > It does build here. :) > That works for me and it's a lot cleaner. I'll make the change. Thanks, Tom -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org