Patch "crypto: qat - disregard spurious PFVF interrupts" has been added to the 4.14-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    crypto: qat - disregard spurious PFVF interrupts

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     crypto-qat-disregard-spurious-pfvf-interrupts.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 8980fdc6bf8e985a067ef74bec7dc267c3a80bb3
Author: Giovanni Cabiddu <giovanni.cabiddu@xxxxxxxxx>
Date:   Tue Sep 28 12:44:30 2021 +0100

    crypto: qat - disregard spurious PFVF interrupts
    
    [ Upstream commit 18fcba469ba5359c1de7e3fb16f7b9e8cd1b8e02 ]
    
    Upon receiving a PFVF message, check if the interrupt bit is set in the
    message. If it is not, that means that the interrupt was probably
    triggered by a collision. In this case, disregard the message and
    re-enable the interrupts.
    
    Fixes: ed8ccaef52fa ("crypto: qat - Add support for SRIOV")
    Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@xxxxxxxxx>
    Reviewed-by: Marco Chiappero <marco.chiappero@xxxxxxxxx>
    Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c b/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c
index 72fd2bbbe704e..180016e157771 100644
--- a/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c
+++ b/drivers/crypto/qat/qat_common/adf_pf2vf_msg.c
@@ -250,6 +250,11 @@ void adf_vf2pf_req_hndl(struct adf_accel_vf_info *vf_info)
 
 	/* Read message from the VF */
 	msg = ADF_CSR_RD(pmisc_addr, hw_data->get_pf2vf_offset(vf_nr));
+	if (!(msg & ADF_VF2PF_INT)) {
+		dev_info(&GET_DEV(accel_dev),
+			 "Spurious VF2PF interrupt, msg %X. Ignored\n", msg);
+		goto out;
+	}
 
 	/* To ACK, clear the VF2PFINT bit */
 	msg &= ~ADF_VF2PF_INT;
@@ -333,6 +338,7 @@ void adf_vf2pf_req_hndl(struct adf_accel_vf_info *vf_info)
 	if (resp && adf_iov_putmsg(accel_dev, resp, vf_nr))
 		dev_err(&GET_DEV(accel_dev), "Failed to send response to VF\n");
 
+out:
 	/* re-enable interrupt on PF from this VF */
 	adf_enable_vf2pf_interrupts(accel_dev, (1 << vf_nr));
 	return;
diff --git a/drivers/crypto/qat/qat_common/adf_vf_isr.c b/drivers/crypto/qat/qat_common/adf_vf_isr.c
index ef90902c8200d..86274e3c6781d 100644
--- a/drivers/crypto/qat/qat_common/adf_vf_isr.c
+++ b/drivers/crypto/qat/qat_common/adf_vf_isr.c
@@ -123,6 +123,11 @@ static void adf_pf2vf_bh_handler(void *data)
 
 	/* Read the message from PF */
 	msg = ADF_CSR_RD(pmisc_bar_addr, hw_data->get_pf2vf_offset(0));
+	if (!(msg & ADF_PF2VF_INT)) {
+		dev_info(&GET_DEV(accel_dev),
+			 "Spurious PF2VF interrupt, msg %X. Ignored\n", msg);
+		goto out;
+	}
 
 	if (!(msg & ADF_PF2VF_MSGORIGIN_SYSTEM))
 		/* Ignore legacy non-system (non-kernel) PF2VF messages */
@@ -171,6 +176,7 @@ static void adf_pf2vf_bh_handler(void *data)
 	msg &= ~ADF_PF2VF_INT;
 	ADF_CSR_WR(pmisc_bar_addr, hw_data->get_pf2vf_offset(0), msg);
 
+out:
 	/* Re-enable PF2VF interrupts */
 	adf_enable_pf2vf_interrupts(accel_dev);
 	return;