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[PULL,6/8] target/riscv: Smepmp: Skip applying default rules when address matches

Message ID 20230224185908.32706-7-palmer@rivosinc.com (mailing list archive)
State New, archived
Headers show
Series [PULL,1/8] hw/riscv: handle 32 bit CPUs kernel_entry in riscv_load_kernel() | expand

Commit Message

Palmer Dabbelt Feb. 24, 2023, 6:59 p.m. UTC 
From: Himanshu Chauhan <hchauhan@ventanamicro.com>

When MSECCFG.MML is set, after checking the address range in PMP if the
asked permissions are not same as programmed in PMP, the default
permissions are applied. This should only be the case when there
is no matching address is found.

This patch skips applying default rules when matching address range
is found. It returns the index of the match PMP entry.

Fixes: 824cac681c3 (target/riscv: Fix PMP propagation for tlb)
Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230209055206.229392-1-hchauhan@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 target/riscv/pmp.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c
index d1126a6066..4bc4113531 100644
--- a/target/riscv/pmp.c
+++ b/target/riscv/pmp.c
@@ -441,9 +441,12 @@  int pmp_hart_has_privs(CPURISCVState *env, target_ulong addr,
                 }
             }
 
-            if ((privs & *allowed_privs) == privs) {
-                ret = i;
-            }
+            /*
+             * If matching address range was found, the protection bits
+             * defined with PMP must be used. We shouldn't fallback on
+             * finding default privileges.
+             */
+            ret = i;
             break;
         }
     }