From f8f6ae5d077a9bdaf5cbf2ac960a5d1a04b47482 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Sun, 1 Nov 2020 17:08:00 -0800 Subject: mm: always have io_remap_pfn_range() set pgprot_decrypted() The purpose of io_remap_pfn_range() is to map IO memory, such as a memory mapped IO exposed through a PCI BAR. IO devices do not understand encryption, so this memory must always be decrypted. Automatically call pgprot_decrypted() as part of the generic implementation. This fixes a bug where enabling AMD SME causes subsystems, such as RDMA, using io_remap_pfn_range() to expose BAR pages to user space to fail. The CPU will encrypt access to those BAR pages instead of passing unencrypted IO directly to the device. Places not mapping IO should use remap_pfn_range(). Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption") Signed-off-by: Jason Gunthorpe Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Tom Lendacky Cc: Thomas Gleixner Cc: Andrey Ryabinin Cc: Borislav Petkov Cc: Brijesh Singh Cc: Jonathan Corbet Cc: Dmitry Vyukov Cc: "Dave Young" Cc: Alexander Potapenko Cc: Konrad Rzeszutek Wilk Cc: Andy Lutomirski Cc: Larry Woodman Cc: Matt Fleming Cc: Ingo Molnar Cc: "Michael S. Tsirkin" Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Rik van Riel Cc: Toshimitsu Kani Cc: Link: https://lkml.kernel.org/r/0-v1-025d64bdf6c4+e-amd_sme_fix_jgg@nvidia.com Signed-off-by: Linus Torvalds --- include/linux/pgtable.h | 4 ---- 1 file changed, 4 deletions(-) (limited to 'include/linux/pgtable.h') diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 38c33eabea89..71125a4676c4 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1427,10 +1427,6 @@ typedef unsigned int pgtbl_mod_mask; #endif /* !__ASSEMBLY__ */ -#ifndef io_remap_pfn_range -#define io_remap_pfn_range remap_pfn_range -#endif - #ifndef has_transparent_hugepage #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define has_transparent_hugepage() 1 -- cgit v1.2.3