Files
android_kernel_xiaomi_sm8450/drivers/char/tpm/tpm_ibmvtpm.h
Stefan Berger 6627be8b36 tpm: ibmvtpm: Avoid error message when process gets signal while waiting
[ Upstream commit 047d4226b0bca1cda5267dc68bc8291cce5364ac ]

When rngd is run as root then lots of these types of message will appear
in the kernel log if the TPM has been configured to provide random bytes:

[ 7406.275163] tpm tpm0: tpm_transmit: tpm_recv: error -4

The issue is caused by the following call that is interrupted while
waiting for the TPM's response.

sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);

Rather than waiting for the response in the low level driver, have it use
the polling loop in tpm_try_transmit() that uses a command's duration to
poll until a result has been returned by the TPM, thus ending when the
timeout has occurred but not responding to signals and ctrl-c anymore. To
stay in this polling loop extend tpm_ibmvtpm_status() to return
'true' for as long as the vTPM is indicated as being busy in
tpm_processing_cmd. Since the loop requires the TPM's timeouts, get them
now using tpm_get_timeouts() after setting the TPM2 version flag on the
chip.

To recreat the resolved issue start rngd like this:

sudo rngd -r /dev/hwrng -t
sudo rngd -r /dev/tpm0 -t

Link: https://bugzilla.redhat.com/show_bug.cgi?id=1981473
Fixes: 6674ff145e ("tpm_ibmvtpm: properly handle interrupted packet receptions")
Cc: Nayna Jain <nayna@linux.ibm.com>
Cc: George Wilson <gcwilson@linux.ibm.com>
Reported-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-15 09:50:30 +02:00

74 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 IBM Corporation
*
* Author: Ashley Lai <ashleydlai@gmail.com>
*
* Maintained by: <tpmdd-devel@lists.sourceforge.net>
*
* Device driver for TCG/TCPA TPM (trusted platform module).
* Specifications at www.trustedcomputinggroup.org
*/
#ifndef __TPM_IBMVTPM_H__
#define __TPM_IBMVTPM_H__
/* vTPM Message Format 1 */
struct ibmvtpm_crq {
u8 valid;
u8 msg;
__be16 len;
__be32 data;
__be64 reserved;
} __attribute__((packed, aligned(8)));
struct ibmvtpm_crq_queue {
struct ibmvtpm_crq *crq_addr;
u32 index;
u32 num_entry;
wait_queue_head_t wq;
};
struct ibmvtpm_dev {
struct device *dev;
struct vio_dev *vdev;
struct ibmvtpm_crq_queue crq_queue;
dma_addr_t crq_dma_handle;
u32 rtce_size;
void __iomem *rtce_buf;
dma_addr_t rtce_dma_handle;
spinlock_t rtce_lock;
wait_queue_head_t wq;
u16 res_len;
u32 vtpm_version;
u8 tpm_processing_cmd;
};
#define CRQ_RES_BUF_SIZE PAGE_SIZE
/* Initialize CRQ */
#define INIT_CRQ_CMD 0xC001000000000000LL /* Init cmd */
#define INIT_CRQ_COMP_CMD 0xC002000000000000LL /* Init complete cmd */
#define INIT_CRQ_RES 0x01 /* Init respond */
#define INIT_CRQ_COMP_RES 0x02 /* Init complete respond */
#define VALID_INIT_CRQ 0xC0 /* Valid command for init crq */
/* vTPM CRQ response is the message type | 0x80 */
#define VTPM_MSG_RES 0x80
#define IBMVTPM_VALID_CMD 0x80
/* vTPM CRQ message types */
#define VTPM_GET_VERSION 0x01
#define VTPM_GET_VERSION_RES (0x01 | VTPM_MSG_RES)
#define VTPM_TPM_COMMAND 0x02
#define VTPM_TPM_COMMAND_RES (0x02 | VTPM_MSG_RES)
#define VTPM_GET_RTCE_BUFFER_SIZE 0x03
#define VTPM_GET_RTCE_BUFFER_SIZE_RES (0x03 | VTPM_MSG_RES)
#define VTPM_PREPARE_TO_SUSPEND 0x04
#define VTPM_PREPARE_TO_SUSPEND_RES (0x04 | VTPM_MSG_RES)
#endif