[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH 1/1] hw/riscv/riscv-iommu.c: Correct the validness check of i
|
From: |
Daniel Henrique Barboza |
|
Subject: |
Re: [PATCH 1/1] hw/riscv/riscv-iommu.c: Correct the validness check of iova |
|
Date: |
Tue, 12 Nov 2024 09:22:17 -0300 |
|
User-agent: |
Mozilla Thunderbird |
On 11/8/24 6:57 AM, Jason Chien wrote:
From RISCV IOMMU spec section 2.1.3:
When SXL is 1, the following rules apply:
- If the first-stage is not Bare, then a page fault corresponding to the
riginal access type occurs if the IOVA has bits beyond bit 31 set to 1.
s/riginal/original
- If the second-stage is not Bare, then a guest page fault corresponding
o the original access type occurs if the incoming GPA has bits beyond bit
33 set to 1.
From RISCV IOMMU spec section 2.3 step 17:
Use the process specified in Section "Two-Stage Address Translation" of
the RISC-V Privileged specification to determine the GPA accessed by the
transaction.
From RISCV IOMMU spec section 2.3 step 19:
Use the second-stage address translation process specified in Section
"Two-Stage Address Translation" of the RISC-V Privileged specification
to translate the GPA A to determine the SPA accessed by the transaction.
This commit adds the iova check with the following rules:
- For Sv32, Sv32x4, Sv39x4, Sv48x4 and Sv57x4, the iova must be zero
extended.
- For Sv39, Sv48 and Sv57, the iova must be signed extended with most
significant bit.
Signed-off-by: Jason Chien <jason.chien@sifive.com>
---
LGTM
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
hw/riscv/riscv-iommu.c | 23 ++++++++++++++++++++---
1 file changed, 20 insertions(+), 3 deletions(-)
diff --git a/hw/riscv/riscv-iommu.c b/hw/riscv/riscv-iommu.c
index bbc95425b3..ff9deefe37 100644
--- a/hw/riscv/riscv-iommu.c
+++ b/hw/riscv/riscv-iommu.c
@@ -392,9 +392,26 @@ static int riscv_iommu_spa_fetch(RISCVIOMMUState *s,
RISCVIOMMUContext *ctx,
/* Address range check before first level lookup */
if (!sc[pass].step) {
- const uint64_t va_mask = (1ULL << (va_skip + va_bits)) - 1;
- if ((addr & va_mask) != addr) {
- return RISCV_IOMMU_FQ_CAUSE_DMA_DISABLED;
+ const uint64_t va_len = va_skip + va_bits;
+ const uint64_t va_mask = (1ULL << va_len) - 1;
+
+ if (pass == S_STAGE && va_len > 32) {
+ target_ulong mask, masked_msbs;
+
+ mask = (1L << (TARGET_LONG_BITS - (va_len - 1))) - 1;
+ masked_msbs = (addr >> (va_len - 1)) & mask;
+
+ if (masked_msbs != 0 && masked_msbs != mask) {
+ return (iotlb->perm & IOMMU_WO) ?
+ RISCV_IOMMU_FQ_CAUSE_WR_FAULT_S :
+ RISCV_IOMMU_FQ_CAUSE_RD_FAULT_S;
+ }
+ } else {
+ if ((addr & va_mask) != addr) {
+ return (iotlb->perm & IOMMU_WO) ?
+ RISCV_IOMMU_FQ_CAUSE_WR_FAULT_VS :
+ RISCV_IOMMU_FQ_CAUSE_RD_FAULT_VS;
+ }
}
}