From: Gilad Ben-Yossef gilad@benyossef.com
commit 15fd2566bf54ee4d4781d8f170acfc9472a1541f upstream.
The PM code was racy, possibly causing the driver to submit requests to a powered down device. Fix the race and while at it simplify the PM code.
Signed-off-by: Gilad Ben-Yossef gilad@benyossef.com Fixes: 1358c13a48c4 ("crypto: ccree - fix resume race condition on init") Cc: stable@kernel.org # v4.20 Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/crypto/ccree/cc_driver.h | 1 drivers/crypto/ccree/cc_pm.c | 28 ++++--------------- drivers/crypto/ccree/cc_request_mgr.c | 50 ---------------------------------- drivers/crypto/ccree/cc_request_mgr.h | 8 ----- 4 files changed, 7 insertions(+), 80 deletions(-)
--- a/drivers/crypto/ccree/cc_driver.h +++ b/drivers/crypto/ccree/cc_driver.h @@ -131,6 +131,7 @@ struct cc_drvdata { u32 axim_mon_offset; u32 sig_offset; u32 ver_offset; + bool pm_on; };
struct cc_crypto_alg { --- a/drivers/crypto/ccree/cc_pm.c +++ b/drivers/crypto/ccree/cc_pm.c @@ -23,14 +23,8 @@ const struct dev_pm_ops ccree_pm = { int cc_pm_suspend(struct device *dev) { struct cc_drvdata *drvdata = dev_get_drvdata(dev); - int rc;
dev_dbg(dev, "set HOST_POWER_DOWN_EN\n"); - rc = cc_suspend_req_queue(drvdata); - if (rc) { - dev_err(dev, "cc_suspend_req_queue (%x)\n", rc); - return rc; - } fini_cc_regs(drvdata); cc_iowrite(drvdata, CC_REG(HOST_POWER_DOWN_EN), POWER_DOWN_ENABLE); cc_clk_off(drvdata); @@ -59,13 +53,6 @@ int cc_pm_resume(struct device *dev) /* check if tee fips error occurred during power down */ cc_tee_handle_fips_error(drvdata);
- rc = cc_resume_req_queue(drvdata); - if (rc) { - dev_err(dev, "cc_resume_req_queue (%x)\n", rc); - return rc; - } - - /* must be after the queue resuming as it uses the HW queue*/ cc_init_hash_sram(drvdata);
cc_init_iv_sram(drvdata); @@ -77,10 +64,8 @@ int cc_pm_get(struct device *dev) int rc = 0; struct cc_drvdata *drvdata = dev_get_drvdata(dev);
- if (cc_req_queue_suspended(drvdata)) + if (drvdata->pm_on) rc = pm_runtime_get_sync(dev); - else - pm_runtime_get_noresume(dev);
return (rc == 1 ? 0 : rc); } @@ -90,14 +75,11 @@ int cc_pm_put_suspend(struct device *dev int rc = 0; struct cc_drvdata *drvdata = dev_get_drvdata(dev);
- if (!cc_req_queue_suspended(drvdata)) { + if (drvdata->pm_on) { pm_runtime_mark_last_busy(dev); rc = pm_runtime_put_autosuspend(dev); - } else { - /* Something wrong happens*/ - dev_err(dev, "request to suspend already suspended queue"); - rc = -EBUSY; } + return rc; }
@@ -108,7 +90,7 @@ int cc_pm_init(struct cc_drvdata *drvdat /* must be before the enabling to avoid resdundent suspending */ pm_runtime_set_autosuspend_delay(dev, CC_SUSPEND_TIMEOUT); pm_runtime_use_autosuspend(dev); - /* activate the PM module */ + /* set us as active - note we won't do PM ops until cc_pm_go()! */ return pm_runtime_set_active(dev); }
@@ -116,9 +98,11 @@ int cc_pm_init(struct cc_drvdata *drvdat void cc_pm_go(struct cc_drvdata *drvdata) { pm_runtime_enable(drvdata_to_dev(drvdata)); + drvdata->pm_on = true; }
void cc_pm_fini(struct cc_drvdata *drvdata) { pm_runtime_disable(drvdata_to_dev(drvdata)); + drvdata->pm_on = false; } --- a/drivers/crypto/ccree/cc_request_mgr.c +++ b/drivers/crypto/ccree/cc_request_mgr.c @@ -41,7 +41,6 @@ struct cc_req_mgr_handle { #else struct tasklet_struct comptask; #endif - bool is_runtime_suspended; };
struct cc_bl_item { @@ -661,52 +660,3 @@ static void comp_handler(unsigned long d
cc_proc_backlog(drvdata); } - -/* - * resume the queue configuration - no need to take the lock as this happens - * inside the spin lock protection - */ -#if defined(CONFIG_PM) -int cc_resume_req_queue(struct cc_drvdata *drvdata) -{ - struct cc_req_mgr_handle *request_mgr_handle = - drvdata->request_mgr_handle; - - spin_lock_bh(&request_mgr_handle->hw_lock); - request_mgr_handle->is_runtime_suspended = false; - spin_unlock_bh(&request_mgr_handle->hw_lock); - - return 0; -} - -/* - * suspend the queue configuration. Since it is used for the runtime suspend - * only verify that the queue can be suspended. - */ -int cc_suspend_req_queue(struct cc_drvdata *drvdata) -{ - struct cc_req_mgr_handle *request_mgr_handle = - drvdata->request_mgr_handle; - - /* lock the send_request */ - spin_lock_bh(&request_mgr_handle->hw_lock); - if (request_mgr_handle->req_queue_head != - request_mgr_handle->req_queue_tail) { - spin_unlock_bh(&request_mgr_handle->hw_lock); - return -EBUSY; - } - request_mgr_handle->is_runtime_suspended = true; - spin_unlock_bh(&request_mgr_handle->hw_lock); - - return 0; -} - -bool cc_req_queue_suspended(struct cc_drvdata *drvdata) -{ - struct cc_req_mgr_handle *request_mgr_handle = - drvdata->request_mgr_handle; - - return request_mgr_handle->is_runtime_suspended; -} - -#endif --- a/drivers/crypto/ccree/cc_request_mgr.h +++ b/drivers/crypto/ccree/cc_request_mgr.h @@ -40,12 +40,4 @@ void complete_request(struct cc_drvdata
void cc_req_mgr_fini(struct cc_drvdata *drvdata);
-#if defined(CONFIG_PM) -int cc_resume_req_queue(struct cc_drvdata *drvdata); - -int cc_suspend_req_queue(struct cc_drvdata *drvdata); - -bool cc_req_queue_suspended(struct cc_drvdata *drvdata); -#endif - #endif /*__REQUEST_MGR_H__*/