From 9667e53573f907d4fcd6accff1c8fe525544b749 Mon Sep 17 00:00:00 2001 From: Dayeol Lee Date: Tue, 22 Oct 2019 21:21:29 +0000 Subject: [PATCH] target/riscv: PMP violation due to wrong size parameter riscv_cpu_tlb_fill() uses the `size` parameter to check PMP violation using pmp_hart_has_privs(). However, if the size is unknown (=0), the ending address will be `addr - 1` as it is `addr + size - 1` in `pmp_hart_has_privs()`. This always causes a false PMP violation on the starting address of the range, as `addr - 1` is not in the range. In order to fix, we just assume that all bytes from addr to the end of the page will be accessed if the size is unknown. Signed-off-by: Dayeol Lee Reviewed-by: Richard Henderson Signed-off-by: Palmer Dabbelt --- target/riscv/pmp.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c index d4f1007109..0e6b640fbd 100644 --- a/target/riscv/pmp.c +++ b/target/riscv/pmp.c @@ -223,6 +223,7 @@ bool pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, { int i = 0; int ret = -1; + int pmp_size = 0; target_ulong s = 0; target_ulong e = 0; pmp_priv_t allowed_privs = 0; @@ -232,11 +233,21 @@ bool pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, return true; } + /* + * if size is unknown (0), assume that all bytes + * from addr to the end of the page will be accessed. + */ + if (size == 0) { + pmp_size = -(addr | TARGET_PAGE_MASK); + } else { + pmp_size = size; + } + /* 1.10 draft priv spec states there is an implicit order from low to high */ for (i = 0; i < MAX_RISCV_PMPS; i++) { s = pmp_is_in_range(env, i, addr); - e = pmp_is_in_range(env, i, addr + size - 1); + e = pmp_is_in_range(env, i, addr + pmp_size - 1); /* partially inside */ if ((s + e) == 1) {