diff options
Diffstat (limited to 'target/linux/mediatek/patches-5.15/350-18-cpufreq-mediatek-fix-KP-caused-by-handler-usage-afte.patch')
| -rw-r--r-- | target/linux/mediatek/patches-5.15/350-18-cpufreq-mediatek-fix-KP-caused-by-handler-usage-afte.patch | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/target/linux/mediatek/patches-5.15/350-18-cpufreq-mediatek-fix-KP-caused-by-handler-usage-afte.patch b/target/linux/mediatek/patches-5.15/350-18-cpufreq-mediatek-fix-KP-caused-by-handler-usage-afte.patch new file mode 100644 index 0000000000..61531d38ad --- /dev/null +++ b/target/linux/mediatek/patches-5.15/350-18-cpufreq-mediatek-fix-KP-caused-by-handler-usage-afte.patch @@ -0,0 +1,149 @@ +From fced531b7c7e18192e7982637c8e8f20c29aad64 Mon Sep 17 00:00:00 2001 +From: Jia-Wei Chang <jia-wei.chang@mediatek.com> +Date: Fri, 24 Mar 2023 18:11:28 +0800 +Subject: [PATCH 18/21] cpufreq: mediatek: fix KP caused by handler usage after + regulator_put/clk_put + +Any kind of failure in mtk_cpu_dvfs_info_init() will lead to calling +regulator_put() or clk_put() and the KP will occur since the regulator/clk +handlers are used after released in mtk_cpu_dvfs_info_release(). + +To prevent the usage after regulator_put()/clk_put(), the regulator/clk +handlers are addressed in a way of "Free the Last Thing Style". + +Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com> +Fixes: 4b9ceb757bbb ("cpufreq: mediatek: Enable clocks and regulators") +Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> +Suggested-by: Dan Carpenter <error27@gmail.com> +Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> +--- + drivers/cpufreq/mediatek-cpufreq.c | 62 +++++++++++++++--------------- + 1 file changed, 30 insertions(+), 32 deletions(-) + +--- a/drivers/cpufreq/mediatek-cpufreq.c ++++ b/drivers/cpufreq/mediatek-cpufreq.c +@@ -420,7 +420,7 @@ static int mtk_cpu_dvfs_info_init(struct + ret = PTR_ERR(info->inter_clk); + dev_err_probe(cpu_dev, ret, + "cpu%d: failed to get intermediate clk\n", cpu); +- goto out_free_resources; ++ goto out_free_mux_clock; + } + + info->proc_reg = regulator_get_optional(cpu_dev, "proc"); +@@ -428,13 +428,13 @@ static int mtk_cpu_dvfs_info_init(struct + ret = PTR_ERR(info->proc_reg); + dev_err_probe(cpu_dev, ret, + "cpu%d: failed to get proc regulator\n", cpu); +- goto out_free_resources; ++ goto out_free_inter_clock; + } + + ret = regulator_enable(info->proc_reg); + if (ret) { + dev_warn(cpu_dev, "cpu%d: failed to enable vproc\n", cpu); +- goto out_free_resources; ++ goto out_free_proc_reg; + } + + /* Both presence and absence of sram regulator are valid cases. */ +@@ -442,14 +442,14 @@ static int mtk_cpu_dvfs_info_init(struct + if (IS_ERR(info->sram_reg)) { + ret = PTR_ERR(info->sram_reg); + if (ret == -EPROBE_DEFER) +- goto out_free_resources; ++ goto out_disable_proc_reg; + + info->sram_reg = NULL; + } else { + ret = regulator_enable(info->sram_reg); + if (ret) { + dev_warn(cpu_dev, "cpu%d: failed to enable vsram\n", cpu); +- goto out_free_resources; ++ goto out_free_sram_reg; + } + } + +@@ -458,13 +458,13 @@ static int mtk_cpu_dvfs_info_init(struct + if (ret) { + dev_err(cpu_dev, + "cpu%d: failed to get OPP-sharing information\n", cpu); +- goto out_free_resources; ++ goto out_disable_sram_reg; + } + + ret = dev_pm_opp_of_cpumask_add_table(&info->cpus); + if (ret) { + dev_warn(cpu_dev, "cpu%d: no OPP table\n", cpu); +- goto out_free_resources; ++ goto out_disable_sram_reg; + } + + ret = clk_prepare_enable(info->cpu_clk); +@@ -533,43 +533,41 @@ out_disable_mux_clock: + out_free_opp_table: + dev_pm_opp_of_cpumask_remove_table(&info->cpus); + +-out_free_resources: +- if (regulator_is_enabled(info->proc_reg)) +- regulator_disable(info->proc_reg); +- if (info->sram_reg && regulator_is_enabled(info->sram_reg)) ++out_disable_sram_reg: ++ if (info->sram_reg) + regulator_disable(info->sram_reg); + +- if (!IS_ERR(info->proc_reg)) +- regulator_put(info->proc_reg); +- if (!IS_ERR(info->sram_reg)) ++out_free_sram_reg: ++ if (info->sram_reg) + regulator_put(info->sram_reg); +- if (!IS_ERR(info->cpu_clk)) +- clk_put(info->cpu_clk); +- if (!IS_ERR(info->inter_clk)) +- clk_put(info->inter_clk); ++ ++out_disable_proc_reg: ++ regulator_disable(info->proc_reg); ++ ++out_free_proc_reg: ++ regulator_put(info->proc_reg); ++ ++out_free_inter_clock: ++ clk_put(info->inter_clk); ++ ++out_free_mux_clock: ++ clk_put(info->cpu_clk); + + return ret; + } + + static void mtk_cpu_dvfs_info_release(struct mtk_cpu_dvfs_info *info) + { +- if (!IS_ERR(info->proc_reg)) { +- regulator_disable(info->proc_reg); +- regulator_put(info->proc_reg); +- } +- if (!IS_ERR(info->sram_reg)) { ++ regulator_disable(info->proc_reg); ++ regulator_put(info->proc_reg); ++ if (info->sram_reg) { + regulator_disable(info->sram_reg); + regulator_put(info->sram_reg); + } +- if (!IS_ERR(info->cpu_clk)) { +- clk_disable_unprepare(info->cpu_clk); +- clk_put(info->cpu_clk); +- } +- if (!IS_ERR(info->inter_clk)) { +- clk_disable_unprepare(info->inter_clk); +- clk_put(info->inter_clk); +- } +- ++ clk_disable_unprepare(info->cpu_clk); ++ clk_put(info->cpu_clk); ++ clk_disable_unprepare(info->inter_clk); ++ clk_put(info->inter_clk); + dev_pm_opp_of_cpumask_remove_table(&info->cpus); + dev_pm_opp_unregister_notifier(info->cpu_dev, &info->opp_nb); + } |