From d40b55bc1b8630a0028f54d9df376930e133cc4a Mon Sep 17 00:00:00 2001 From: Jiaxun Yang Date: Fri, 6 Nov 2020 12:21:45 +0800 Subject: [PATCH] target/mips: Fix PageMask with variable page size MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Our current code assumed the target page size is always 4k when handling PageMask and VPN2, however, variable page size was just added to mips target and that's no longer true. Fixes: ee3863b9d414 ("target/mips: Support variable page size") Signed-off-by: Jiaxun Yang Signed-off-by: Huacai Chen Message-Id: <1604636510-8347-2-git-send-email-chenhc@lemote.com> Tested-by: Philippe Mathieu-Daudé [PMD: Replaced find_first_zero_bit() by cto32()] Signed-off-by: Philippe Mathieu-Daudé --- target/mips/cp0_helper.c | 27 +++++++++++++++++++++------ target/mips/cpu.h | 1 + 2 files changed, 22 insertions(+), 6 deletions(-) diff --git a/target/mips/cp0_helper.c b/target/mips/cp0_helper.c index 709cc9a7e3..a1b5140cca 100644 --- a/target/mips/cp0_helper.c +++ b/target/mips/cp0_helper.c @@ -892,13 +892,28 @@ void helper_mtc0_memorymapid(CPUMIPSState *env, target_ulong arg1) void update_pagemask(CPUMIPSState *env, target_ulong arg1, int32_t *pagemask) { - uint64_t mask = arg1 >> (TARGET_PAGE_BITS + 1); - if (!(env->insn_flags & ISA_MIPS32R6) || (arg1 == ~0) || - (mask == 0x0000 || mask == 0x0003 || mask == 0x000F || - mask == 0x003F || mask == 0x00FF || mask == 0x03FF || - mask == 0x0FFF || mask == 0x3FFF || mask == 0xFFFF)) { - env->CP0_PageMask = arg1 & (0x1FFFFFFF & (TARGET_PAGE_MASK << 1)); + uint32_t mask; + int maskbits; + + /* Don't care MASKX as we don't support 1KB page */ + mask = extract32((uint32_t)arg1, CP0PM_MASK, 16); + maskbits = cto32(mask); + + /* Ensure no more set bit after first zero */ + if ((mask >> maskbits) != 0) { + goto invalid; } + /* We don't support VTLB entry smaller than target page */ + if ((maskbits + 12) < TARGET_PAGE_BITS) { + goto invalid; + } + env->CP0_PageMask = mask << CP0PM_MASK; + + return; + +invalid: + /* When invalid, set to default target page size. */ + env->CP0_PageMask = (~TARGET_PAGE_MASK >> 12) << CP0PM_MASK; } void helper_mtc0_pagemask(CPUMIPSState *env, target_ulong arg1) diff --git a/target/mips/cpu.h b/target/mips/cpu.h index d41579d44a..23f8c6f96c 100644 --- a/target/mips/cpu.h +++ b/target/mips/cpu.h @@ -619,6 +619,7 @@ struct CPUMIPSState { * CP0 Register 5 */ int32_t CP0_PageMask; +#define CP0PM_MASK 13 int32_t CP0_PageGrain_rw_bitmask; int32_t CP0_PageGrain; #define CP0PG_RIE 31