cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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processor-flags.h (1750B)


      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef _ASM_X86_PROCESSOR_FLAGS_H
      3#define _ASM_X86_PROCESSOR_FLAGS_H
      4
      5#include <uapi/asm/processor-flags.h>
      6#include <linux/mem_encrypt.h>
      7
      8#ifdef CONFIG_VM86
      9#define X86_VM_MASK	X86_EFLAGS_VM
     10#else
     11#define X86_VM_MASK	0 /* No VM86 support */
     12#endif
     13
     14/*
     15 * CR3's layout varies depending on several things.
     16 *
     17 * If CR4.PCIDE is set (64-bit only), then CR3[11:0] is the address space ID.
     18 * If PAE is enabled, then CR3[11:5] is part of the PDPT address
     19 * (i.e. it's 32-byte aligned, not page-aligned) and CR3[4:0] is ignored.
     20 * Otherwise (non-PAE, non-PCID), CR3[3] is PWT, CR3[4] is PCD, and
     21 * CR3[2:0] and CR3[11:5] are ignored.
     22 *
     23 * In all cases, Linux puts zeros in the low ignored bits and in PWT and PCD.
     24 *
     25 * CR3[63] is always read as zero.  If CR4.PCIDE is set, then CR3[63] may be
     26 * written as 1 to prevent the write to CR3 from flushing the TLB.
     27 *
     28 * On systems with SME, one bit (in a variable position!) is stolen to indicate
     29 * that the top-level paging structure is encrypted.
     30 *
     31 * All of the remaining bits indicate the physical address of the top-level
     32 * paging structure.
     33 *
     34 * CR3_ADDR_MASK is the mask used by read_cr3_pa().
     35 */
     36#ifdef CONFIG_X86_64
     37/* Mask off the address space ID and SME encryption bits. */
     38#define CR3_ADDR_MASK	__sme_clr(0x7FFFFFFFFFFFF000ull)
     39#define CR3_PCID_MASK	0xFFFull
     40#define CR3_NOFLUSH	BIT_ULL(63)
     41
     42#else
     43/*
     44 * CR3_ADDR_MASK needs at least bits 31:5 set on PAE systems, and we save
     45 * a tiny bit of code size by setting all the bits.
     46 */
     47#define CR3_ADDR_MASK	0xFFFFFFFFull
     48#define CR3_PCID_MASK	0ull
     49#define CR3_NOFLUSH	0
     50#endif
     51
     52#ifdef CONFIG_PAGE_TABLE_ISOLATION
     53# define X86_CR3_PTI_PCID_USER_BIT	11
     54#endif
     55
     56#endif /* _ASM_X86_PROCESSOR_FLAGS_H */