bybrooklyn/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-04-18 06:44:00 -04:00
Code Issues Packages Projects Releases Wiki Activity

firmware: qcom: scm: initialize tzmem before marking SCM as available

Browse Source 
Now that qcom_scm_shm_bridge_enable() uses the struct device passed to
it as argument to make the QCOM_SCM_MP_SHM_BRIDGE_ENABLE SCM call, we
can move the TZMem initialization before the assignment of the __scm
pointer in the SCM driver (which marks SCM as ready to users) thus
fixing the potential race between consumer calls and the memory pool
initialization.

Reported-by: Johan Hovold <johan+linaro@kernel.org>
Closes: https://lore.kernel.org/all/20250120151000.13870-1-johan+linaro@kernel.org/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20250630-qcom-scm-race-v2-3-fa3851c98611@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
This commit is contained in:
Bartosz Golaszewski
2025-06-30 14:12:04 +02:00
committed by Bjorn Andersson
parent dc3f4e75c5
commit 87be3e7a2d
1 changed files with 26 additions and 27 deletions
Download Patch File Download Diff File Expand all files Collapse all files

53
drivers/firmware/qcom/qcom_scm.c
View File

@@ -2256,7 +2256,32 @@ static int qcom_scm_probe(struct platform_device *pdev)
if (ret)
return ret;
/* Paired with smp_load_acquire() in qcom_scm_is_available(). */
ret = of_reserved_mem_device_init(scm->dev);
if (ret && ret != -ENODEV)
return dev_err_probe(scm->dev, ret,
"Failed to setup the reserved memory region for TZ mem\n");
ret = qcom_tzmem_enable(scm->dev);
if (ret)
return dev_err_probe(scm->dev, ret,
"Failed to enable the TrustZone memory allocator\n");
memset(&pool_config, 0, sizeof(pool_config));
pool_config.initial_size = 0;
pool_config.policy = QCOM_TZMEM_POLICY_ON_DEMAND;
pool_config.max_size = SZ_256K;
scm->mempool = devm_qcom_tzmem_pool_new(scm->dev, &pool_config);
if (IS_ERR(scm->mempool))
return dev_err_probe(scm->dev, PTR_ERR(scm->mempool),
"Failed to create the SCM memory pool\n");
/*
* Paired with smp_load_acquire() in qcom_scm_is_available().
*
* This marks the SCM API as ready to accept user calls and can only
* be called after the TrustZone memory pool is initialized.
*/
smp_store_release(&__scm, scm);
irq = platform_get_irq_optional(pdev, 0);
@@ -2289,32 +2314,6 @@ static int qcom_scm_probe(struct platform_device *pdev)
if (of_property_read_bool(pdev->dev.of_node, "qcom,sdi-enabled") || !download_mode)
qcom_scm_disable_sdi();
ret = of_reserved_mem_device_init(__scm->dev);
if (ret && ret != -ENODEV) {
dev_err_probe(__scm->dev, ret,
"Failed to setup the reserved memory region for TZ mem\n");
goto err;
}
ret = qcom_tzmem_enable(__scm->dev);
if (ret) {
dev_err_probe(__scm->dev, ret,
"Failed to enable the TrustZone memory allocator\n");
goto err;
}
memset(&pool_config, 0, sizeof(pool_config));
pool_config.initial_size = 0;
pool_config.policy = QCOM_TZMEM_POLICY_ON_DEMAND;
pool_config.max_size = SZ_256K;
__scm->mempool = devm_qcom_tzmem_pool_new(__scm->dev, &pool_config);
if (IS_ERR(__scm->mempool)) {
ret = dev_err_probe(__scm->dev, PTR_ERR(__scm->mempool),
"Failed to create the SCM memory pool\n");
goto err;
}
/*
* Initialize the QSEECOM interface.
*