KVM: riscv: SBI FWFT: Apply LOCK flag only on successful set

kvm_sbi_fwft_set() applies the caller's flags to conf->flags before
invoking the set() callback. If the callback returns an error, the LOCK
bit persists and the feature becomes permanently locked without its value
ever being changed.

Move the flags assignment after the callback so LOCK takes effect only
on success.

Fixes: 6b72fd170592 ("RISC-V: KVM: add support for FWFT SBI extension")
Signed-off-by: SeungJu Cheon <suunj1331@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260624130238.524706-1-suunj1331@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>

diff --git a/arch/riscv/kvm/vcpu_sbi_fwft.c b/arch/riscv/kvm/vcpu_sbi_fwft.c
index ab39ac464ffd817035e4938131562bc80a4ecf88..1342adb3180c6f1a5b730db321506ae24489c543 100644 (file)
--- a/arch/riscv/kvm/vcpu_sbi_fwft.c
+++ b/arch/riscv/kvm/vcpu_sbi_fwft.c
@@ -327,9 +327,11 @@ static int kvm_sbi_fwft_set(struct kvm_vcpu *vcpu, u32 feature,
        if (conf->flags & SBI_FWFT_SET_FLAG_LOCK)
                return SBI_ERR_DENIED_LOCKED;
 
-       conf->flags = flags;
+       ret = conf->feature->set(vcpu, conf, false, value);
+       if (ret == SBI_SUCCESS)
+               conf->flags = flags;
 
-       return conf->feature->set(vcpu, conf, false, value);
+       return ret;
 }
 
 static int kvm_sbi_fwft_get(struct kvm_vcpu *vcpu, unsigned long feature,