On PARTITION_INFO_GET error paths, Xen unconditionally called FFA_RX_RELEASE for the SPMC RX buffer. If the SPMC didn't grant RX ownership (i.e., the call failed early), this issues a spurious release that returns DENIED and produces warnings.
Modify ffa_rxtx_spmc_rx_release() to return the release status and let callers choose whether to log it. Only issue FFA_RX_RELEASE after a successful PARTINFO SMC, while always releasing the local RX lock to avoid deadlocks. Update handle_partition_info_get() to only release the SPMC RX buffer after successful fw_ret checks, and ignore release errors during the error path. Functional impact: eliminates spurious FFA_RX_RELEASE calls and associated DENIED warnings when PARTITION_INFO_GET fails before obtaining SPMC RX buffer ownership. Signed-off-by: Bertrand Marquis <[email protected]> --- xen/arch/arm/tee/ffa_partinfo.c | 14 ++++++++++++-- xen/arch/arm/tee/ffa_private.h | 2 +- xen/arch/arm/tee/ffa_rxtx.c | 14 +++++++++----- 3 files changed, 22 insertions(+), 8 deletions(-) diff --git a/xen/arch/arm/tee/ffa_partinfo.c b/xen/arch/arm/tee/ffa_partinfo.c index bf906ed0c88f..6b01c4abe915 100644 --- a/xen/arch/arm/tee/ffa_partinfo.c +++ b/xen/arch/arm/tee/ffa_partinfo.c @@ -92,9 +92,11 @@ static int32_t ffa_get_sp_partinfo(struct ffa_uuid uuid, uint32_t *sp_count, uint32_t dst_size) { int32_t ret; + int32_t release_ret; uint32_t src_size, real_sp_count; void *src_buf; uint32_t count = 0; + bool spmc_ok = false; /* We need to use the RX buffer to receive the list */ src_buf = ffa_rxtx_spmc_rx_acquire(); @@ -104,6 +106,7 @@ static int32_t ffa_get_sp_partinfo(struct ffa_uuid uuid, uint32_t *sp_count, ret = ffa_partition_info_get(uuid, 0, &real_sp_count, &src_size); if ( ret ) goto out; + spmc_ok = true; /* Validate the src_size we got */ if ( src_size < sizeof(struct ffa_partition_info_1_0) || @@ -157,7 +160,10 @@ static int32_t ffa_get_sp_partinfo(struct ffa_uuid uuid, uint32_t *sp_count, *sp_count = count; out: - ffa_rxtx_spmc_rx_release(); + release_ret = ffa_rxtx_spmc_rx_release(spmc_ok); + if ( release_ret ) + gprintk(XENLOG_WARNING, + "ffa: Error releasing SPMC RX buffer: %d\n", release_ret); return ret; } @@ -507,6 +513,7 @@ bool ffa_partinfo_init(void) int32_t e; void *spmc_rx; struct ffa_uuid nil_uuid = { .val = { 0ULL, 0ULL } }; + bool spmc_ok = false; if ( !ffa_fw_supports_fid(FFA_PARTITION_INFO_GET) || !ffa_fw_supports_fid(FFA_MSG_SEND_DIRECT_REQ_32)) @@ -522,6 +529,7 @@ bool ffa_partinfo_init(void) printk(XENLOG_ERR "ffa: Failed to get list of SPs: %d\n", e); goto out; } + spmc_ok = true; if ( count >= FFA_MAX_NUM_SP ) { @@ -533,7 +541,9 @@ bool ffa_partinfo_init(void) ret = init_subscribers(spmc_rx, count, fpi_size); out: - ffa_rxtx_spmc_rx_release(); + e = ffa_rxtx_spmc_rx_release(spmc_ok); + if ( e ) + printk(XENLOG_WARNING "ffa: Error releasing SPMC RX buffer: %d\n", e); return ret; } diff --git a/xen/arch/arm/tee/ffa_private.h b/xen/arch/arm/tee/ffa_private.h index 58562d8e733c..461e87f6f9c4 100644 --- a/xen/arch/arm/tee/ffa_private.h +++ b/xen/arch/arm/tee/ffa_private.h @@ -458,7 +458,7 @@ int32_t ffa_endpoint_domain_lookup(uint16_t endpoint_id, struct domain **d_out, bool ffa_rxtx_spmc_init(void); void ffa_rxtx_spmc_destroy(void); void *ffa_rxtx_spmc_rx_acquire(void); -void ffa_rxtx_spmc_rx_release(void); +int32_t ffa_rxtx_spmc_rx_release(bool notify_fw); void *ffa_rxtx_spmc_tx_acquire(void); void ffa_rxtx_spmc_tx_release(void); diff --git a/xen/arch/arm/tee/ffa_rxtx.c b/xen/arch/arm/tee/ffa_rxtx.c index 7d8bb4f4d031..50758fb57cdf 100644 --- a/xen/arch/arm/tee/ffa_rxtx.c +++ b/xen/arch/arm/tee/ffa_rxtx.c @@ -375,18 +375,22 @@ void *ffa_rxtx_spmc_rx_acquire(void) return NULL; } -void ffa_rxtx_spmc_rx_release(void) +int32_t ffa_rxtx_spmc_rx_release(bool notify_fw) { int32_t ret; ASSERT(spin_is_locked(&ffa_spmc_rx_lock)); - /* Inform the SPMC that we are done with our RX buffer */ - ret = ffa_simple_call(FFA_RX_RELEASE, 0, 0, 0, 0); - if ( ret != FFA_RET_OK ) - printk(XENLOG_DEBUG "Error releasing SPMC RX buffer: %d\n", ret); + if ( notify_fw ) + { + /* Inform the SPMC that we are done with our RX buffer */ + ret = ffa_simple_call(FFA_RX_RELEASE, 0, 0, 0, 0); + } + else + ret = FFA_RET_OK; spin_unlock(&ffa_spmc_rx_lock); + return ret; } void *ffa_rxtx_spmc_tx_acquire(void) -- 2.50.1 (Apple Git-155)
