Address Translation Fault is triggered when PA size set by VTCR_EL2.PS is less than IPA
size set by VTCR_EL2.T0SZ on the guest. (e.g. vtcr_el2.PS = 1 && vtcr_el2.T0SZ
= 25. PA size is 36bit, and IPA size is 39bit.)
ps = FIELD_EX64(cpu->isar.id_aa64mmfr0, ID_AA64MMFR0, PARANGE);
ps = MIN(ps, param.ps);
assert(ps < ARRAY_SIZE(pamax_map));
outputsize = pamax_map[ps];
When 'param.ps' determined by VTCR_EL2.PS less than 'ps', 'outputsize' is set
to PA address by VTCR_EL2.PS.
--
Keisuke Iida
On 2022/05/05 17:20, Peter Maydell wrote:
On Thu, 5 May 2022 at 01:40,<m...@sfc.wide.ad.jp> wrote:
From: Keisuke Iida<m...@sfc.wide.ad.jp>
The maximum IPA size('inputsize') is constrained by the implemented PA size
that is
specified by ID_AA64MMFR0_EL1.PARange. Please reference Arm Architecture
Reference
Manual for A-profile architecture "Supported IPA size" on page D5-4788.
Signed-off-by: Keisuke Iida<m...@sfc.wide.ad.jp>
---
target/arm/helper.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/target/arm/helper.c b/target/arm/helper.c
index 5a244c3ed9..868e7a2c0b 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -11116,7 +11116,7 @@ static bool check_s2_mmu_setup(ARMCPU *cpu, bool
is_aa64, int level,
}
/* Inputsize checks. */
- if (inputsize > outputsize &&
+ if (inputsize > arm_pamax(cpu) &&
(arm_el_is_aa64(&cpu->env, 1) || inputsize > 40)) {
/* This is CONSTRAINED UNPREDICTABLE and we choose to fault. */
return false;
Can you give an example, eg a test case, where you see wrong
behaviour? The 'outputsize' variable in this function is
passed in from the caller get_phys_addr_lpae(), where (for
an AArch64 guest) it is indeed constrained to the value
of ID_AA64MMFR0.PARange:
/*
* Bound PS by PARANGE to find the effective output address size.
* ID_AA64MMFR0 is a read-only register so values outside of the
* supported mappings can be considered an implementation error.
*/
ps = FIELD_EX64(cpu->isar.id_aa64mmfr0, ID_AA64MMFR0, PARANGE);
ps = MIN(ps, param.ps);
assert(ps < ARRAY_SIZE(pamax_map));
outputsize = pamax_map[ps];
thanks
-- PMM
