From 3f5952917498e7bb9d227812d4349668f62c413b Mon Sep 17 00:00:00 2001 From: Per Larsen Date: Wed, 20 Aug 2025 01:10:09 +0000 Subject: [PATCH] KVM: arm64: Mask response to FFA_FEATURE call The minimum size and alignment boundary for FFA_RXTX_MAP is returned in bit[1:0]. Mask off any other bits in w2 when reading the minimum buffer size in hyp_ffa_post_init. Acked-by: Will Deacon Signed-off-by: Per Larsen Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/nvhe/ffa.c | 2 +- include/linux/arm_ffa.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c index 96109aa99c487..a8ec1a94f3f8a 100644 --- a/arch/arm64/kvm/hyp/nvhe/ffa.c +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c @@ -739,7 +739,7 @@ static int hyp_ffa_post_init(void) if (res.a0 != FFA_SUCCESS) return -EOPNOTSUPP; - switch (res.a2) { + switch (res.a2 & FFA_FEAT_RXTX_MIN_SZ_MASK) { case FFA_FEAT_RXTX_MIN_SZ_4K: min_rxtx_sz = SZ_4K; break; diff --git a/include/linux/arm_ffa.h b/include/linux/arm_ffa.h index e1634897e159c..cd7ee4df9045d 100644 --- a/include/linux/arm_ffa.h +++ b/include/linux/arm_ffa.h @@ -128,6 +128,7 @@ #define FFA_FEAT_RXTX_MIN_SZ_4K 0 #define FFA_FEAT_RXTX_MIN_SZ_64K 1 #define FFA_FEAT_RXTX_MIN_SZ_16K 2 +#define FFA_FEAT_RXTX_MIN_SZ_MASK GENMASK(1, 0) /* FFA Bus/Device/Driver related */ struct ffa_device { -- 2.47.3