February 2023 - Linux-stable-mirror

[PATCH 11/23] interconnect: qcom: msm8974: fix registration race

by Johan Hovold

The current interconnect provider registration interface is inherently racy as nodes are not added until the after adding the provider. This can specifically cause racing DT lookups to fail. Switch to using the new API where the provider is not registered until after it has been fully initialised. Fixes: 4e60a9568dc6 ("interconnect: qcom: add msm8974 driver") Cc: stable(a)vger.kernel.org # 5.5 Cc: Brian Masney <bmasney(a)redhat.com> Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org> --- drivers/interconnect/qcom/msm8974.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/drivers/interconnect/qcom/msm8974.c b/drivers/interconnect/qcom/msm8974.c index 5ea192f1141d..1828deaca443 100644 --- a/drivers/interconnect/qcom/msm8974.c +++ b/drivers/interconnect/qcom/msm8974.c @@ -692,7 +692,6 @@ static int msm8974_icc_probe(struct platform_device *pdev) return ret; provider = &qp->provider; - INIT_LIST_HEAD(&provider->nodes); provider->dev = dev; provider->set = msm8974_icc_set; provider->aggregate = icc_std_aggregate; @@ -700,11 +699,7 @@ static int msm8974_icc_probe(struct platform_device *pdev) provider->data = data; provider->get_bw = msm8974_get_bw; - ret = icc_provider_add(provider); - if (ret) { - dev_err(dev, "error adding interconnect provider: %d\n", ret); - goto err_disable_clks; - } + icc_provider_init(provider); for (i = 0; i < num_nodes; i++) { size_t j; @@ -712,7 +707,7 @@ static int msm8974_icc_probe(struct platform_device *pdev) node = icc_node_create(qnodes[i]->id); if (IS_ERR(node)) { ret = PTR_ERR(node); - goto err_del_icc; + goto err_remove_nodes; } node->name = qnodes[i]->name; @@ -729,15 +724,16 @@ static int msm8974_icc_probe(struct platform_device *pdev) } data->num_nodes = num_nodes; + ret = icc_provider_register(provider); + if (ret) + goto err_remove_nodes; + platform_set_drvdata(pdev, qp); return 0; -err_del_icc: +err_remove_nodes: icc_nodes_remove(provider); - icc_provider_del(provider); - -err_disable_clks: clk_bulk_disable_unprepare(qp->num_clks, qp->bus_clks); return ret; @@ -747,9 +743,9 @@ static int msm8974_icc_remove(struct platform_device *pdev) { struct msm8974_icc_provider *qp = platform_get_drvdata(pdev); + icc_provider_deregister(&qp->provider); icc_nodes_remove(&qp->provider); clk_bulk_disable_unprepare(qp->num_clks, qp->bus_clks); - icc_provider_del(&qp->provider); return 0; } -- 2.39.1

1 year, 3 months

3
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[PATCH 10/23] interconnect: qcom: rpmh: fix registration race

by Johan Hovold

The current interconnect provider registration interface is inherently racy as nodes are not added until the after adding the provider. This can specifically cause racing DT lookups to fail. Switch to using the new API where the provider is not registered until after it has been fully initialised. Fixes: 976daac4a1c5 ("interconnect: qcom: Consolidate interconnect RPMh support") Cc: stable(a)vger.kernel.org # 5.7 Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org> --- drivers/interconnect/qcom/icc-rpmh.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/interconnect/qcom/icc-rpmh.c b/drivers/interconnect/qcom/icc-rpmh.c index 5168bbf3d92f..fdb5e58e408b 100644 --- a/drivers/interconnect/qcom/icc-rpmh.c +++ b/drivers/interconnect/qcom/icc-rpmh.c @@ -192,9 +192,10 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev) provider->pre_aggregate = qcom_icc_pre_aggregate; provider->aggregate = qcom_icc_aggregate; provider->xlate_extended = qcom_icc_xlate_extended; - INIT_LIST_HEAD(&provider->nodes); provider->data = data; + icc_provider_init(provider); + qp->dev = dev; qp->bcms = desc->bcms; qp->num_bcms = desc->num_bcms; @@ -203,10 +204,6 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev) if (IS_ERR(qp->voter)) return PTR_ERR(qp->voter); - ret = icc_provider_add(provider); - if (ret) - return ret; - for (i = 0; i < qp->num_bcms; i++) qcom_icc_bcm_init(qp->bcms[i], dev); @@ -218,7 +215,7 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev) node = icc_node_create(qn->id); if (IS_ERR(node)) { ret = PTR_ERR(node); - goto err; + goto err_remove_nodes; } node->name = qn->name; @@ -232,19 +229,27 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev) } data->num_nodes = num_nodes; + + ret = icc_provider_register(provider); + if (ret) + goto err_remove_nodes; + platform_set_drvdata(pdev, qp); /* Populate child NoC devices if any */ if (of_get_child_count(dev->of_node) > 0) { ret = of_platform_populate(dev->of_node, NULL, NULL, dev); if (ret) - goto err; + goto err_deregister_provider; } return 0; -err: + +err_deregister_provider: + icc_provider_deregister(provider); +err_remove_nodes: icc_nodes_remove(provider); - icc_provider_del(provider); + return ret; } EXPORT_SYMBOL_GPL(qcom_icc_rpmh_probe); @@ -253,8 +258,8 @@ int qcom_icc_rpmh_remove(struct platform_device *pdev) { struct qcom_icc_provider *qp = platform_get_drvdata(pdev); + icc_provider_deregister(&qp->provider); icc_nodes_remove(&qp->provider); - icc_provider_del(&qp->provider); return 0; } -- 2.39.1

1 year, 3 months

2
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[PATCH 09/23] interconnect: qcom: rpmh: fix probe child-node error handling

by Johan Hovold

Make sure to clean up and release resources properly also in case probe fails when populating child devices. Fixes: 57eb14779dfd ("interconnect: qcom: icc-rpmh: Support child NoC device probe") Cc: stable(a)vger.kernel.org # 6.0 Cc: Luca Weiss <luca.weiss(a)fairphone.com> Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org> --- drivers/interconnect/qcom/icc-rpmh.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/interconnect/qcom/icc-rpmh.c b/drivers/interconnect/qcom/icc-rpmh.c index fd17291c61eb..5168bbf3d92f 100644 --- a/drivers/interconnect/qcom/icc-rpmh.c +++ b/drivers/interconnect/qcom/icc-rpmh.c @@ -235,8 +235,11 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev) platform_set_drvdata(pdev, qp); /* Populate child NoC devices if any */ - if (of_get_child_count(dev->of_node) > 0) - return of_platform_populate(dev->of_node, NULL, NULL, dev); + if (of_get_child_count(dev->of_node) > 0) { + ret = of_platform_populate(dev->of_node, NULL, NULL, dev); + if (ret) + goto err; + } return 0; err: -- 2.39.1

1 year, 3 months

2
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[PATCH 06/23] interconnect: qcom: rpm: fix probe child-node error handling

by Johan Hovold

Make sure to clean up and release resources properly also in case probe fails when populating child devices. Fixes: e39bf2972c6e ("interconnect: icc-rpm: Support child NoC device probe") Cc: stable(a)vger.kernel.org # 5.17 Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org> --- drivers/interconnect/qcom/icc-rpm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/interconnect/qcom/icc-rpm.c b/drivers/interconnect/qcom/icc-rpm.c index df3196f72536..91778cfcbc65 100644 --- a/drivers/interconnect/qcom/icc-rpm.c +++ b/drivers/interconnect/qcom/icc-rpm.c @@ -541,8 +541,11 @@ int qnoc_probe(struct platform_device *pdev) platform_set_drvdata(pdev, qp); /* Populate child NoC devices if any */ - if (of_get_child_count(dev->of_node) > 0) - return of_platform_populate(dev->of_node, NULL, NULL, dev); + if (of_get_child_count(dev->of_node) > 0) { + ret = of_platform_populate(dev->of_node, NULL, NULL, dev); + if (ret) + goto err; + } return 0; err: -- 2.39.1

1 year, 3 months

2
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[PATCH 05/23] interconnect: qcom: osm-l3: fix registration race

by Johan Hovold

The current interconnect provider registration interface is inherently racy as nodes are not added until the after adding the provider. This can specifically cause racing DT lookups to fail: of_icc_xlate_onecell: invalid index 0 cpu cpu0: error -EINVAL: error finding src node cpu cpu0: dev_pm_opp_of_find_icc_paths: Unable to get path0: -22 qcom-cpufreq-hw: probe of 18591000.cpufreq failed with error -22 Switch to using the new API where the provider is not registered until after it has been fully initialised. Fixes: 5bc9900addaf ("interconnect: qcom: Add OSM L3 interconnect provider support") Cc: stable(a)vger.kernel.org # 5.7 Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org> --- drivers/interconnect/qcom/osm-l3.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/interconnect/qcom/osm-l3.c b/drivers/interconnect/qcom/osm-l3.c index 5fa171087425..3a1cbfe3e481 100644 --- a/drivers/interconnect/qcom/osm-l3.c +++ b/drivers/interconnect/qcom/osm-l3.c @@ -158,8 +158,8 @@ static int qcom_osm_l3_remove(struct platform_device *pdev) { struct qcom_osm_l3_icc_provider *qp = platform_get_drvdata(pdev); + icc_provider_deregister(&qp->provider); icc_nodes_remove(&qp->provider); - icc_provider_del(&qp->provider); return 0; } @@ -245,14 +245,9 @@ static int qcom_osm_l3_probe(struct platform_device *pdev) provider->set = qcom_osm_l3_set; provider->aggregate = icc_std_aggregate; provider->xlate = of_icc_xlate_onecell; - INIT_LIST_HEAD(&provider->nodes); provider->data = data; - ret = icc_provider_add(provider); - if (ret) { - dev_err(&pdev->dev, "error adding interconnect provider\n"); - return ret; - } + icc_provider_init(provider); for (i = 0; i < num_nodes; i++) { size_t j; @@ -275,12 +270,15 @@ static int qcom_osm_l3_probe(struct platform_device *pdev) } data->num_nodes = num_nodes; + ret = icc_provider_register(provider); + if (ret) + goto err; + platform_set_drvdata(pdev, qp); return 0; err: icc_nodes_remove(provider); - icc_provider_del(provider); return ret; } -- 2.39.1

1 year, 3 months

2
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[PATCH 03/23] interconnect: fix provider registration API

by Johan Hovold

The current interconnect provider interface is inherently racy as providers are expected to be added before being fully initialised. Specifically, nodes are currently not added and the provider data is not initialised until after registering the provider which can cause racing DT lookups to fail. Add a new provider API which will be used to fix up the interconnect drivers. The old API is reimplemented using the new interface and will be removed once all drivers have been fixed. Fixes: 11f1ceca7031 ("interconnect: Add generic on-chip interconnect API") Fixes: 87e3031b6fbd ("interconnect: Allow endpoints translation via DT") Cc: stable(a)vger.kernel.org # 5.1 Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org> --- drivers/interconnect/core.c | 52 +++++++++++++++++++-------- include/linux/interconnect-provider.h | 12 +++++++ 2 files changed, 50 insertions(+), 14 deletions(-) diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c index 43c5c8503ee8..93d27ff8eef6 100644 --- a/drivers/interconnect/core.c +++ b/drivers/interconnect/core.c @@ -1030,44 +1030,68 @@ int icc_nodes_remove(struct icc_provider *provider) EXPORT_SYMBOL_GPL(icc_nodes_remove); /** - * icc_provider_add() - add a new interconnect provider - * @provider: the interconnect provider that will be added into topology + * icc_provider_init() - initialize a new interconnect provider + * @provider: the interconnect provider to initialize + * + * Must be called before adding nodes to the provider. + */ +void icc_provider_init(struct icc_provider *provider) +{ + WARN_ON(!provider->set); + + INIT_LIST_HEAD(&provider->nodes); +} +EXPORT_SYMBOL_GPL(icc_provider_init); + +/** + * icc_provider_register() - register a new interconnect provider + * @provider: the interconnect provider to register * * Return: 0 on success, or an error code otherwise */ -int icc_provider_add(struct icc_provider *provider) +int icc_provider_register(struct icc_provider *provider) { - if (WARN_ON(!provider->set)) - return -EINVAL; if (WARN_ON(!provider->xlate && !provider->xlate_extended)) return -EINVAL; mutex_lock(&icc_lock); - - INIT_LIST_HEAD(&provider->nodes); list_add_tail(&provider->provider_list, &icc_providers); - mutex_unlock(&icc_lock); - dev_dbg(provider->dev, "interconnect provider added to topology\n"); + dev_dbg(provider->dev, "interconnect provider registered\n"); return 0; } -EXPORT_SYMBOL_GPL(icc_provider_add); +EXPORT_SYMBOL_GPL(icc_provider_register); /** - * icc_provider_del() - delete previously added interconnect provider - * @provider: the interconnect provider that will be removed from topology + * icc_provider_deregister() - deregister an interconnect provider + * @provider: the interconnect provider to deregister */ -void icc_provider_del(struct icc_provider *provider) +void icc_provider_deregister(struct icc_provider *provider) { mutex_lock(&icc_lock); WARN_ON(provider->users); - WARN_ON(!list_empty(&provider->nodes)); list_del(&provider->provider_list); mutex_unlock(&icc_lock); } +EXPORT_SYMBOL_GPL(icc_provider_deregister); + +int icc_provider_add(struct icc_provider *provider) +{ + icc_provider_init(provider); + + return icc_provider_register(provider); +} +EXPORT_SYMBOL_GPL(icc_provider_add); + +void icc_provider_del(struct icc_provider *provider) +{ + WARN_ON(!list_empty(&provider->nodes)); + + icc_provider_deregister(provider); +} EXPORT_SYMBOL_GPL(icc_provider_del); static const struct of_device_id __maybe_unused ignore_list[] = { diff --git a/include/linux/interconnect-provider.h b/include/linux/interconnect-provider.h index cd5c5a27557f..d12cd18aab3f 100644 --- a/include/linux/interconnect-provider.h +++ b/include/linux/interconnect-provider.h @@ -122,6 +122,9 @@ int icc_link_destroy(struct icc_node *src, struct icc_node *dst); void icc_node_add(struct icc_node *node, struct icc_provider *provider); void icc_node_del(struct icc_node *node); int icc_nodes_remove(struct icc_provider *provider); +void icc_provider_init(struct icc_provider *provider); +int icc_provider_register(struct icc_provider *provider); +void icc_provider_deregister(struct icc_provider *provider); int icc_provider_add(struct icc_provider *provider); void icc_provider_del(struct icc_provider *provider); struct icc_node_data *of_icc_get_from_provider(struct of_phandle_args *spec); @@ -167,6 +170,15 @@ static inline int icc_nodes_remove(struct icc_provider *provider) return -ENOTSUPP; } +static inline void icc_provider_init(struct icc_provider *provider) { } + +static inline int icc_provider_register(struct icc_provider *provider) +{ + return -ENOTSUPP; +} + +static inline void icc_provider_deregister(struct icc_provider *provider) { } + static inline int icc_provider_add(struct icc_provider *provider) { return -ENOTSUPP; -- 2.39.1

1 year, 3 months

2
1
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[PATCH] bcache: Remove some unnecessary NULL point check for the return value of __bch_btree_node_alloc-related pointer

by Zheng Wang

Due to the previously fix of __bch_btree_node_alloc, the return value will never be a NULL pointer. So IS_ERR is enough to handle the failure situation. Fix it by replacing IS_ERR_OR_NULL check to IS_ERR check. Fixes: cafe56359144 ("bcache: A block layer cache") Signed-off-by: Zheng Wang <zyytlz.wz(a)163.com> --- drivers/md/bcache/btree.c | 6 +++--- drivers/md/bcache/super.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index 147c493a989a..417cd7c436c4 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -1138,7 +1138,7 @@ static struct btree *btree_node_alloc_replacement(struct btree *b, { struct btree *n = bch_btree_node_alloc(b->c, op, b->level, b->parent); - if (!IS_ERR_OR_NULL(n)) { + if (!IS_ERR(n)) { mutex_lock(&n->write_lock); bch_btree_sort_into(&b->keys, &n->keys, &b->c->sort); bkey_copy_key(&n->key, &b->key); @@ -1352,7 +1352,7 @@ static int btree_gc_coalesce(struct btree *b, struct btree_op *op, for (i = 0; i < nodes; i++) { new_nodes[i] = btree_node_alloc_replacement(r[i].b, NULL); - if (IS_ERR_OR_NULL(new_nodes[i])) + if (IS_ERR(new_nodes[i])) goto out_nocoalesce; } @@ -1669,7 +1669,7 @@ static int bch_btree_gc_root(struct btree *b, struct btree_op *op, if (should_rewrite) { n = btree_node_alloc_replacement(b, NULL); - if (!IS_ERR_OR_NULL(n)) { + if (!IS_ERR(n)) { bch_btree_node_write_sync(n); bch_btree_set_root(n); diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index ba3909bb6bea..92de714fe75e 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -2088,7 +2088,7 @@ static int run_cache_set(struct cache_set *c) err = "cannot allocate new btree root"; c->root = __bch_btree_node_alloc(c, NULL, 0, true, NULL); - if (IS_ERR_OR_NULL(c->root)) + if (IS_ERR(c->root)) goto err; mutex_lock(&c->root->write_lock); -- 2.25.1

1 year, 3 months

4
4
0 0

[PATCH 4.19 v2 00/15] Backport oops_limit to 4.19

by Eric Biggers

This series backports the patchset "exit: Put an upper limit on how often we can oops" (https://lore.kernel.org/linux-mm/20221117233838.give.484-kees@kernel.org/T/…) to 4.19, as recommended at https://googleprojectzero.blogspot.com/2023/01/exploiting-null-dereferences… Changed in v2: - Fixed a build error in mm/kasan/report.c by dropping the patch "mm: kasan: do not panic if both panic_on_warn and kasan_multishot set". Eric W. Biederman (2): exit: Add and use make_task_dead. objtool: Add a missing comma to avoid string concatenation Jann Horn (1): exit: Put an upper limit on how often we can oops Kees Cook (7): exit: Expose "oops_count" to sysfs exit: Allow oops_limit to be disabled panic: Consolidate open-coded panic_on_warn checks panic: Introduce warn_limit panic: Expose "warn_count" to sysfs docs: Fix path paste-o for /sys/kernel/warn_count exit: Use READ_ONCE() for all oops/warn limit reads Nathan Chancellor (2): hexagon: Fix function name in die() h8300: Fix build errors from do_exit() to make_task_dead() transition Randy Dunlap (1): ia64: make IA64_MCA_RECOVERY bool instead of tristate Tiezhu Yang (1): panic: unset panic_on_warn inside panic() Xiaoming Ni (1): sysctl: add a new register_sysctl_init() interface .../ABI/testing/sysfs-kernel-oops_count | 6 ++ .../ABI/testing/sysfs-kernel-warn_count | 6 ++ Documentation/sysctl/kernel.txt | 20 +++++ arch/alpha/kernel/traps.c | 6 +- arch/alpha/mm/fault.c | 2 +- arch/arm/kernel/traps.c | 2 +- arch/arm/mm/fault.c | 2 +- arch/arm64/kernel/traps.c | 2 +- arch/arm64/mm/fault.c | 2 +- arch/h8300/kernel/traps.c | 3 +- arch/h8300/mm/fault.c | 2 +- arch/hexagon/kernel/traps.c | 2 +- arch/ia64/Kconfig | 2 +- arch/ia64/kernel/mca_drv.c | 2 +- arch/ia64/kernel/traps.c | 2 +- arch/ia64/mm/fault.c | 2 +- arch/m68k/kernel/traps.c | 2 +- arch/m68k/mm/fault.c | 2 +- arch/microblaze/kernel/exceptions.c | 4 +- arch/mips/kernel/traps.c | 2 +- arch/nds32/kernel/traps.c | 8 +- arch/nios2/kernel/traps.c | 4 +- arch/openrisc/kernel/traps.c | 2 +- arch/parisc/kernel/traps.c | 2 +- arch/powerpc/kernel/traps.c | 2 +- arch/riscv/kernel/traps.c | 2 +- arch/riscv/mm/fault.c | 2 +- arch/s390/kernel/dumpstack.c | 2 +- arch/s390/kernel/nmi.c | 2 +- arch/sh/kernel/traps.c | 2 +- arch/sparc/kernel/traps_32.c | 4 +- arch/sparc/kernel/traps_64.c | 4 +- arch/x86/entry/entry_32.S | 6 +- arch/x86/entry/entry_64.S | 6 +- arch/x86/kernel/dumpstack.c | 4 +- arch/xtensa/kernel/traps.c | 2 +- fs/proc/proc_sysctl.c | 33 ++++++++ include/linux/kernel.h | 1 + include/linux/sched/task.h | 1 + include/linux/sysctl.h | 3 + kernel/exit.c | 72 ++++++++++++++++++ kernel/panic.c | 75 ++++++++++++++++--- kernel/sched/core.c | 3 +- mm/kasan/report.c | 3 +- tools/objtool/check.c | 3 +- 45 files changed, 257 insertions(+), 64 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-kernel-oops_count create mode 100644 Documentation/ABI/testing/sysfs-kernel-warn_count base-commit: b17faf2c4e88ac0deb894f068bda67ace57e9c0a -- 2.39.1

1 year, 3 months

1
15
0 0

+ mm-shrinkers-fix-deadlock-in-shrinker-debugfs.patch added to mm-unstable branch

by Andrew Morton

The patch titled Subject: mm: shrinkers: fix deadlock in shrinker debugfs has been added to the -mm mm-unstable branch. Its filename is mm-shrinkers-fix-deadlock-in-shrinker-debugfs.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Qi Zheng <zhengqi.arch(a)bytedance.com> Subject: mm: shrinkers: fix deadlock in shrinker debugfs Date: Thu, 2 Feb 2023 18:56:12 +0800 The debugfs_remove_recursive() is invoked by unregister_shrinker(), which is holding the write lock of shrinker_rwsem. It will waits for the handler of debugfs file complete. The handler also needs to hold the read lock of shrinker_rwsem to do something. So it may cause the following deadlock: CPU0 CPU1 debugfs_file_get() shrinker_debugfs_count_show()/shrinker_debugfs_scan_write() unregister_shrinker() --> down_write(&shrinker_rwsem); debugfs_remove_recursive() // wait for (A) --> wait_for_completion(); // wait for (B) --> down_read_killable(&shrinker_rwsem) debugfs_file_put() -- (A) up_write() -- (B) The down_read_killable() can be killed, so that the above deadlock can be recovered. But it still requires an extra kill action, otherwise it will block all subsequent shrinker-related operations, so it's better to fix it. Link: https://lkml.kernel.org/r/20230202105612.64641-1-zhengqi.arch@bytedance.com Fixes: 5035ebc644ae ("mm: shrinkers: introduce debugfs interface for memory shrinkers") Signed-off-by: Qi Zheng <zhengqi.arch(a)bytedance.com> Cc: Roman Gushchin <roman.gushchin(a)linux.dev> Cc: Kent Overstreet <kent.overstreet(a)gmail.com> Cc: Muchun Song <songmuchun(a)bytedance.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- --- a/include/linux/shrinker.h~mm-shrinkers-fix-deadlock-in-shrinker-debugfs +++ a/include/linux/shrinker.h @@ -107,7 +107,7 @@ extern void synchronize_shrinkers(void); #ifdef CONFIG_SHRINKER_DEBUG extern int shrinker_debugfs_add(struct shrinker *shrinker); -extern void shrinker_debugfs_remove(struct shrinker *shrinker); +extern struct dentry *shrinker_debugfs_remove(struct shrinker *shrinker); extern int __printf(2, 3) shrinker_debugfs_rename(struct shrinker *shrinker, const char *fmt, ...); #else /* CONFIG_SHRINKER_DEBUG */ @@ -115,7 +115,7 @@ static inline int shrinker_debugfs_add(s { return 0; } -static inline void shrinker_debugfs_remove(struct shrinker *shrinker) +static inline struct dentry *shrinker_debugfs_remove(struct shrinker *shrinker) { } static inline __printf(2, 3) --- a/mm/shrinker_debug.c~mm-shrinkers-fix-deadlock-in-shrinker-debugfs +++ a/mm/shrinker_debug.c @@ -246,18 +246,21 @@ int shrinker_debugfs_rename(struct shrin } EXPORT_SYMBOL(shrinker_debugfs_rename); -void shrinker_debugfs_remove(struct shrinker *shrinker) +struct dentry *shrinker_debugfs_remove(struct shrinker *shrinker) { + struct dentry *entry = shrinker->debugfs_entry; + lockdep_assert_held(&shrinker_rwsem); kfree_const(shrinker->name); shrinker->name = NULL; - if (!shrinker->debugfs_entry) - return; + if (entry) { + ida_free(&shrinker_debugfs_ida, shrinker->debugfs_id); + shrinker->debugfs_entry = NULL; + } - debugfs_remove_recursive(shrinker->debugfs_entry); - ida_free(&shrinker_debugfs_ida, shrinker->debugfs_id); + return entry; } static int __init shrinker_debugfs_init(void) --- a/mm/vmscan.c~mm-shrinkers-fix-deadlock-in-shrinker-debugfs +++ a/mm/vmscan.c @@ -747,6 +747,8 @@ EXPORT_SYMBOL(register_shrinker); */ void unregister_shrinker(struct shrinker *shrinker) { + struct dentry *debugfs_entry; + if (!(shrinker->flags & SHRINKER_REGISTERED)) return; @@ -755,9 +757,11 @@ void unregister_shrinker(struct shrinker shrinker->flags &= ~SHRINKER_REGISTERED; if (shrinker->flags & SHRINKER_MEMCG_AWARE) unregister_memcg_shrinker(shrinker); - shrinker_debugfs_remove(shrinker); + debugfs_entry = shrinker_debugfs_remove(shrinker); up_write(&shrinker_rwsem); + debugfs_remove_recursive(debugfs_entry); + kfree(shrinker->nr_deferred); shrinker->nr_deferred = NULL; } _ Patches currently in -mm which might be from zhengqi.arch(a)bytedance.com are mm-shrinkers-fix-deadlock-in-shrinker-debugfs.patch

1 year, 3 months

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[PATCH 5.15.y v2 0/5] phy: qcom-qmp-combo: Backport some stable fixes

by Stephen Boyd

After the qmp phy driver was split it looks like 5.15.y stable kernels aren't getting fixes like commit 7a7d86d14d07 ("phy: qcom-qmp-combo: fix broken power on") which is tagged for stable 5.10. Trogdor boards use the qmp phy on 5.15.y kernels, so I backported the fixes I could find that looked like we may possibly trip over at some point. USB and DP work on my Trogdor.Lazor board with this set. Changes from v1 (https://lore.kernel.org/r/20230113005405.3992011-1-swboyd@chromium.org): * New patch for memleak on probe deferal to avoid compat issues * Update "fix broken power on" patch for pcie/ufs phy Johan Hovold (5): phy: qcom-qmp-combo: disable runtime PM on unbind phy: qcom-qmp-combo: fix memleak on probe deferral phy: qcom-qmp-usb: fix memleak on probe deferral phy: qcom-qmp-combo: fix broken power on phy: qcom-qmp-combo: fix runtime suspend drivers/phy/qualcomm/phy-qcom-qmp.c | 97 ++++++++++++++++++----------- 1 file changed, 61 insertions(+), 36 deletions(-) Cc: Johan Hovold <johan+linaro(a)kernel.org> Cc: Dmitry Baryshkov <dmitry.baryshkov(a)linaro.org> Cc: Vinod Koul <vkoul(a)kernel.org> base-commit: d57287729e229188e7d07ef0117fe927664e08cb -- https://chromeos.dev

1 year, 3 months

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Linux-stable-mirror February 2023