When protected KVM is enabled, the kernel includes a pKVM FF-A proxy that sits in front of the normal FF-A driver. The proxy has to perform its own FF-A version negotiation and setup first, so that it can mediate subsequent FF-A traffic correctly.
Defer FF-A core probing until pKVM has completed initialization. This keeps the normal driver from negotiating the FF-A version or performing other transport setup before the pKVM proxy is ready, and lets the driver model retry probing once the protected KVM state required by the FF-A transport is available. Suggested-by: Yeoreum Yun <[email protected]> Signed-off-by: Sudeep Holla <[email protected]> --- drivers/firmware/arm_ffa/driver.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index e9d7dc71c06d..1fba064c2aba 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -43,6 +43,8 @@ #include <linux/uuid.h> #include <linux/xarray.h> +#include <asm/virt.h> + #include "common.h" #define FFA_DRIVER_VERSION FFA_VERSION_1_2 @@ -2039,6 +2041,10 @@ static int ffa_probe(struct platform_device *pdev) u32 buf_sz; size_t rxtx_bufsz = SZ_4K; + if (IS_BUILTIN(CONFIG_ARM_FFA_TRANSPORT) && + is_protected_kvm_enabled() && !is_pkvm_initialized()) + return -EPROBE_DEFER; + ret = ffa_transport_init(&invoke_ffa_fn); if (ret) return ret; -- 2.43.0
