kernel/linux.git/drivers/soc/qcom/pdr_interface.c, branch v6.12.80

soc: qcom: pdr: Fix the potential deadlock

2025-03-28T21:03:31+00:00

commit 2eeb03ad9f42dfece63051be2400af487ddb96d2 upstream. When some client process A call pdr_add_lookup() to add the look up for the service and does schedule locator work, later a process B got a new server packet indicating locator is up and call pdr_locator_new_server() which eventually sets pdr->locator_init_complete to true which process A sees and takes list lock and queries domain list but it will timeout due to deadlock as the response will queued to the same qmi->wq and it is ordered workqueue and process B is not able to complete new server request work due to deadlock on list lock. Fix it by removing the unnecessary list iteration as the list iteration is already being done inside locator work, so avoid it here and just call schedule_work() here. Process A Process B process_scheduled_works() pdr_add_lookup() qmi_data_ready_work() process_scheduled_works() pdr_locator_new_server() pdr->locator_init_complete=true; pdr_locator_work() mutex_lock(&pdr->list_lock); pdr_locate_service() mutex_lock(&pdr->list_lock); pdr_get_domain_list() pr_err("PDR: %s get domain list txn wait failed: %d\n", req->service_name, ret); Timeout error log due to deadlock: " PDR: tms/servreg get domain list txn wait failed: -110 PDR: service lookup for msm/adsp/sensor_pd:tms/servreg failed: -110 " Thanks to Bjorn and Johan for letting me know that this commit also fixes an audio regression when using the in-kernel pd-mapper as that makes it easier to hit this race. [1] Link: https://lore.kernel.org/lkml/Zqet8iInnDhnxkT9@hovoldconsulting.com/ # [1] Fixes: fbe639b44a82 ("soc: qcom: Introduce Protection Domain Restart helpers") CC: stable@vger.kernel.org Reviewed-by: Bjorn Andersson Tested-by: Bjorn Andersson Tested-by: Johan Hovold Signed-off-by: Saranya R Co-developed-by: Mukesh Ojha Signed-off-by: Mukesh Ojha Link: https://lore.kernel.org/r/20250212163720.1577876-1-mukesh.ojha@oss.qualcomm.com Signed-off-by: Bjorn Andersson Signed-off-by: Greg Kroah-Hartman

soc: qcom: pdr: simplify with cleanup.h

2024-07-06T17:56:50+00:00

Allocate the memory with scoped/cleanup.h to reduce error handling (less error paths) and make the code a bit simpler. Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20240703-thermal-const-v1-4-6e59e139c65d@linaro.org Signed-off-by: Bjorn Andersson

soc: qcom: pdr: fix parsing of domains lists

2024-06-24T03:41:39+00:00

While parsing the domains list, start offsets from 0 rather than from domains_read. The domains_read is equal to the total count of the domains we have seen, while the domains list in the message starts from offset 0. Fixes: fbe639b44a82 ("soc: qcom: Introduce Protection Domain Restart helpers") Tested-by: Steev Klimaszewski Tested-by: Alexey Minnekhanov Reviewed-by: Chris Lew Tested-by: Neil Armstrong # on SM8550-QRD Signed-off-by: Dmitry Baryshkov Link: https://lore.kernel.org/r/20240622-qcom-pd-mapper-v9-2-a84ee3591c8e@linaro.org Signed-off-by: Bjorn Andersson

soc: qcom: pdr: protect locator_addr with the main mutex

2024-06-24T03:41:39+00:00

If the service locator server is restarted fast enough, the PDR can rewrite locator_addr fields concurrently. Protect them by placing modification of those fields under the main pdr->lock. Fixes: fbe639b44a82 ("soc: qcom: Introduce Protection Domain Restart helpers") Tested-by: Neil Armstrong # on SM8550-QRD Tested-by: Steev Klimaszewski Tested-by: Alexey Minnekhanov Signed-off-by: Dmitry Baryshkov Link: https://lore.kernel.org/r/20240622-qcom-pd-mapper-v9-1-a84ee3591c8e@linaro.org Signed-off-by: Bjorn Andersson

soc: qcom: Switch to EXPORT_SYMBOL_GPL()

2023-09-27T23:08:38+00:00

Switch to GPL version of EXPORT_SYMBOL for Qualcomm SoC drivers. Signed-off-by: Unnathi Chalicheemala Reviewed-by: Trilok Soni Link: https://lore.kernel.org/r/20230922184817.5183-1-quic_uchalich@quicinc.com Signed-off-by: Bjorn Andersson

soc: qcom: pdr: replace usage of found with dedicated list iterator variable

2022-04-08T03:20:27+00:00

To move the list iterator variable into the list_for_each_entry_*() macro in the future it should be avoided to use the list iterator variable after the loop body. To *never* use the list iterator variable after the loop it was concluded to use a separate iterator variable instead of a found boolean [1]. This removes the need to use a found variable and simply checking if the variable was set, can determine if the break/goto was hit. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ Signed-off-by: Jakob Koschel Signed-off-by: Bjorn Andersson Link: https://lore.kernel.org/r/20220324072435.63070-1-jakobkoschel@gmail.com

soc: qcom: pdr: Prefer strscpy over strcpy

2021-09-21T22:41:49+00:00

strcpy() performs no bounds checking on the destination buffer. This could result in linear overflows beyond the end of the buffer, leading to all kinds of misbehaviors. The safe replacement is strscpy(). This is a previous step in the path to remove the strcpy() function entirely from the kernel. Signed-off-by: Len Baker Signed-off-by: Bjorn Andersson Link: https://lore.kernel.org/r/20210808125012.4715-2-len.baker@gmx.com

soc: qcom: pdr: Fix error return code in pdr_register_listener

2021-04-08T03:31:39+00:00

Fix to return the error code -EREMOTEIO from pdr_register_listener rather than 0. Fixes: fbe639b44a82 ("soc: qcom: Introduce Protection Domain Restart helpers") Reported-by: Hulk Robot Signed-off-by: Qinglang Miao Link: https://lore.kernel.org/r/20201125065034.154217-1-miaoqinglang@huawei.com Signed-off-by: Bjorn Andersson

soc: qcom: pdr: Constify static qmi structs

2020-11-23T05:06:23+00:00

Their only usage is to pass their address to qmi_handle_init() which accepts const pointers to both qmi_ops and qmi_msg_handler. Make them const to allow the compiler to put them in read-only memory. Signed-off-by: Rikard Falkeborn Link: https://lore.kernel.org/r/20201122232818.32072-1-rikard.falkeborn@gmail.com Signed-off-by: Bjorn Andersson

soc: qcom: initialize local variable

2020-11-22T03:51:42+00:00

clang static analysis reports this problem pdr_interface.c:596:6: warning: Branch condition evaluates to a garbage value if (!req.service_path[0]) ^~~~~~~~~~~~~~~~~~~~ This check that req.service_path was set in an earlier loop. However req is a stack variable and its initial value is undefined. So initialize req to 0. Fixes: fbe639b44a82 ("soc: qcom: Introduce Protection Domain Restart helpers") Reviewed-by: Sibi Sankar Signed-off-by: Tom Rix Link: https://lore.kernel.org/r/20200819184637.15648-1-trix@redhat.com Signed-off-by: Bjorn Andersson