From 991ec97625e1281ba22bd81426a7226a76baf60a Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 25 Feb 2022 15:42:06 +0100 Subject: [PATCH] target/i386: only include bits in pg_mode if they are not ignored LA57/PKE/PKS is only relevant in 64-bit mode, and NXE is only relevant if PAE is in use. Since there is code that checks PG_MODE_LA57 to determine the canonicality of addresses, make sure that the bit is not set by mistake in 32-bit mode. While it would not be a problem because 32-bit addresses by definition fit in both 48-bit and 57-bit address spaces, it is nicer if get_pg_mode() actually returns whether a feature is enabled, and it allows a few simplifications in the page table walker. Signed-off-by: Paolo Bonzini --- target/i386/tcg/sysemu/excp_helper.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/target/i386/tcg/sysemu/excp_helper.c b/target/i386/tcg/sysemu/excp_helper.c index 5627772e7c..6f1fbe667b 100644 --- a/target/i386/tcg/sysemu/excp_helper.c +++ b/target/i386/tcg/sysemu/excp_helper.c @@ -25,32 +25,35 @@ int get_pg_mode(CPUX86State *env) { int pg_mode = 0; + if (!(env->cr[0] & CR0_PG_MASK)) { + return 0; + } if (env->cr[0] & CR0_WP_MASK) { pg_mode |= PG_MODE_WP; } if (env->cr[4] & CR4_PAE_MASK) { pg_mode |= PG_MODE_PAE; + if (env->efer & MSR_EFER_NXE) { + pg_mode |= PG_MODE_NXE; + } } if (env->cr[4] & CR4_PSE_MASK) { pg_mode |= PG_MODE_PSE; } - if (env->cr[4] & CR4_PKE_MASK) { - pg_mode |= PG_MODE_PKE; - } - if (env->cr[4] & CR4_PKS_MASK) { - pg_mode |= PG_MODE_PKS; - } if (env->cr[4] & CR4_SMEP_MASK) { pg_mode |= PG_MODE_SMEP; } - if (env->cr[4] & CR4_LA57_MASK) { - pg_mode |= PG_MODE_LA57; - } if (env->hflags & HF_LMA_MASK) { pg_mode |= PG_MODE_LMA; - } - if (env->efer & MSR_EFER_NXE) { - pg_mode |= PG_MODE_NXE; + if (env->cr[4] & CR4_PKE_MASK) { + pg_mode |= PG_MODE_PKE; + } + if (env->cr[4] & CR4_PKS_MASK) { + pg_mode |= PG_MODE_PKS; + } + if (env->cr[4] & CR4_LA57_MASK) { + pg_mode |= PG_MODE_LA57; + } } return pg_mode; } @@ -279,9 +282,7 @@ do_check_protect_pse36: *prot |= PAGE_EXEC; } - if (!(pg_mode & PG_MODE_LMA)) { - pkr = 0; - } else if (ptep & PG_USER_MASK) { + if (ptep & PG_USER_MASK) { pkr = pg_mode & PG_MODE_PKE ? env->pkru : 0; } else { pkr = pg_mode & PG_MODE_PKS ? env->pkrs : 0; @@ -344,8 +345,7 @@ do_check_protect_pse36: if (is_user) error_code |= PG_ERROR_U_MASK; if (is_write1 == 2 && - (((pg_mode & PG_MODE_NXE) && (pg_mode & PG_MODE_PAE)) || - (pg_mode & PG_MODE_SMEP))) + ((pg_mode & PG_MODE_NXE) || (pg_mode & PG_MODE_SMEP))) error_code |= PG_ERROR_I_D_MASK; return error_code; } -- 2.11.4.GIT