Commit 9b206e5265 for qemu.org

commit 9b206e52655044da7f639c193a6ff3cec21baa02
Author: Stefan Berger <stefanb@linux.vnet.ibm.com>
Date:   Fri Oct 2 10:25:12 2026 -0400

    hw/tpm: crb: Do not clear internal buffers when backend is busy

    While the backend (thread) is accessing the request and response buffers,
    do not clear those buffers upon a command cancellation. Also, per CRB spec
    the TPM is expected to either return a normal command response (command
    could not be cancelled) or an error response indicating TPM_RC_CANCELED.
    So the response buffer must be able to receive a response as normal.

    Fixes: 29315d22b259 ("hw/tpm: Add internal buffer state for chunking")
    Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
    Reviewed-by: Arun Menon <armenon@redhat.com>
    Link: https://lore.kernel.org/qemu-devel/20261002142516.2063735-7-stefanb@linux.ibm.com
    Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
index 54fa2042b5..daf451aa56 100644
--- a/hw/tpm/tpm_crb.c
+++ b/hw/tpm/tpm_crb.c
@@ -219,7 +219,6 @@ static void tpm_crb_mmio_write(void *opaque, hwaddr addr,
             if (s->regs[R_CRB_CTRL_START] & CRB_START_INVOKE) {
                 tpm_backend_cancel_cmd(s->tpmbe);
             }
-            tpm_crb_clear_internal_buffers(s);
         }
         break;
     case A_CRB_CTRL_START: