February 2024 - Linux-stable-mirror

[merged mm-hotfixes-stable] fs-proc-do_task_stat-use-sig-stats_lock-to-gather-the-threads-children-stats.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats has been removed from the -mm tree. Its filename was fs-proc-do_task_stat-use-sig-stats_lock-to-gather-the-threads-children-stats.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Oleg Nesterov <oleg(a)redhat.com> Subject: fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats Date: Tue, 23 Jan 2024 16:33:57 +0100 lock_task_sighand() can trigger a hard lockup. If NR_CPUS threads call do_task_stat() at the same time and the process has NR_THREADS, it will spin with irqs disabled O(NR_CPUS * NR_THREADS) time. Change do_task_stat() to use sig->stats_lock to gather the statistics outside of ->siglock protected section, in the likely case this code will run lockless. Link: https://lkml.kernel.org/r/20240123153357.GA21857@redhat.com Signed-off-by: Oleg Nesterov <oleg(a)redhat.com> Signed-off-by: Dylan Hatch <dylanbhatch(a)google.com> Cc: Eric W. Biederman <ebiederm(a)xmission.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- fs/proc/array.c | 58 +++++++++++++++++++++++++--------------------- 1 file changed, 32 insertions(+), 26 deletions(-) --- a/fs/proc/array.c~fs-proc-do_task_stat-use-sig-stats_lock-to-gather-the-threads-children-stats +++ a/fs/proc/array.c @@ -477,13 +477,13 @@ static int do_task_stat(struct seq_file int permitted; struct mm_struct *mm; unsigned long long start_time; - unsigned long cmin_flt = 0, cmaj_flt = 0; - unsigned long min_flt = 0, maj_flt = 0; - u64 cutime, cstime, utime, stime; - u64 cgtime, gtime; + unsigned long cmin_flt, cmaj_flt, min_flt, maj_flt; + u64 cutime, cstime, cgtime, utime, stime, gtime; unsigned long rsslim = 0; unsigned long flags; int exit_code = task->exit_code; + struct signal_struct *sig = task->signal; + unsigned int seq = 1; state = *get_task_state(task); vsize = eip = esp = 0; @@ -511,12 +511,8 @@ static int do_task_stat(struct seq_file sigemptyset(&sigign); sigemptyset(&sigcatch); - cutime = cstime = 0; - cgtime = gtime = 0; if (lock_task_sighand(task, &flags)) { - struct signal_struct *sig = task->signal; - if (sig->tty) { struct pid *pgrp = tty_get_pgrp(sig->tty); tty_pgrp = pid_nr_ns(pgrp, ns); @@ -527,27 +523,9 @@ static int do_task_stat(struct seq_file num_threads = get_nr_threads(task); collect_sigign_sigcatch(task, &sigign, &sigcatch); - cmin_flt = sig->cmin_flt; - cmaj_flt = sig->cmaj_flt; - cutime = sig->cutime; - cstime = sig->cstime; - cgtime = sig->cgtime; rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur); - /* add up live thread stats at the group level */ if (whole) { - struct task_struct *t; - - __for_each_thread(sig, t) { - min_flt += t->min_flt; - maj_flt += t->maj_flt; - gtime += task_gtime(t); - } - - min_flt += sig->min_flt; - maj_flt += sig->maj_flt; - gtime += sig->gtime; - if (sig->flags & (SIGNAL_GROUP_EXIT | SIGNAL_STOP_STOPPED)) exit_code = sig->group_exit_code; } @@ -562,6 +540,34 @@ static int do_task_stat(struct seq_file if (permitted && (!whole || num_threads < 2)) wchan = !task_is_running(task); + do { + seq++; /* 2 on the 1st/lockless path, otherwise odd */ + flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq); + + cmin_flt = sig->cmin_flt; + cmaj_flt = sig->cmaj_flt; + cutime = sig->cutime; + cstime = sig->cstime; + cgtime = sig->cgtime; + + if (whole) { + struct task_struct *t; + + min_flt = sig->min_flt; + maj_flt = sig->maj_flt; + gtime = sig->gtime; + + rcu_read_lock(); + __for_each_thread(sig, t) { + min_flt += t->min_flt; + maj_flt += t->maj_flt; + gtime += task_gtime(t); + } + rcu_read_unlock(); + } + } while (need_seqretry(&sig->stats_lock, seq)); + done_seqretry_irqrestore(&sig->stats_lock, seq, flags); + if (whole) { thread_group_cputime_adjusted(task, &utime, &stime); } else { _ Patches currently in -mm which might be from oleg(a)redhat.com are ptrace_attach-shift-sendsigstop-into-ptrace_set_stopped.patch

10 months, 3 weeks

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[merged mm-hotfixes-stable] fs-proc-do_task_stat-move-thread_group_cputime_adjusted-outside-of-lock_task_sighand.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: fs/proc: do_task_stat: move thread_group_cputime_adjusted() outside of lock_task_sighand() has been removed from the -mm tree. Its filename was fs-proc-do_task_stat-move-thread_group_cputime_adjusted-outside-of-lock_task_sighand.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Oleg Nesterov <oleg(a)redhat.com> Subject: fs/proc: do_task_stat: move thread_group_cputime_adjusted() outside of lock_task_sighand() Date: Tue, 23 Jan 2024 16:33:55 +0100 Patch series "fs/proc: do_task_stat: use sig->stats_". do_task_stat() has the same problem as getrusage() had before "getrusage: use sig->stats_lock rather than lock_task_sighand()": a hard lockup. If NR_CPUS threads call lock_task_sighand() at the same time and the process has NR_THREADS, spin_lock_irq will spin with irqs disabled O(NR_CPUS * NR_THREADS) time. This patch (of 3): thread_group_cputime() does its own locking, we can safely shift thread_group_cputime_adjusted() which does another for_each_thread loop outside of ->siglock protected section. Not only this removes for_each_thread() from the critical section with irqs disabled, this removes another case when stats_lock is taken with siglock held. We want to remove this dependency, then we can change the users of stats_lock to not disable irqs. Link: https://lkml.kernel.org/r/20240123153313.GA21832@redhat.com Link: https://lkml.kernel.org/r/20240123153355.GA21854@redhat.com Signed-off-by: Oleg Nesterov <oleg(a)redhat.com> Signed-off-by: Dylan Hatch <dylanbhatch(a)google.com> Cc: Eric W. Biederman <ebiederm(a)xmission.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- fs/proc/array.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/fs/proc/array.c~fs-proc-do_task_stat-move-thread_group_cputime_adjusted-outside-of-lock_task_sighand +++ a/fs/proc/array.c @@ -511,7 +511,7 @@ static int do_task_stat(struct seq_file sigemptyset(&sigign); sigemptyset(&sigcatch); - cutime = cstime = utime = stime = 0; + cutime = cstime = 0; cgtime = gtime = 0; if (lock_task_sighand(task, &flags)) { @@ -546,7 +546,6 @@ static int do_task_stat(struct seq_file min_flt += sig->min_flt; maj_flt += sig->maj_flt; - thread_group_cputime_adjusted(task, &utime, &stime); gtime += sig->gtime; if (sig->flags & (SIGNAL_GROUP_EXIT | SIGNAL_STOP_STOPPED)) @@ -562,10 +561,13 @@ static int do_task_stat(struct seq_file if (permitted && (!whole || num_threads < 2)) wchan = !task_is_running(task); - if (!whole) { + + if (whole) { + thread_group_cputime_adjusted(task, &utime, &stime); + } else { + task_cputime_adjusted(task, &utime, &stime); min_flt = task->min_flt; maj_flt = task->maj_flt; - task_cputime_adjusted(task, &utime, &stime); gtime = task_gtime(task); } _ Patches currently in -mm which might be from oleg(a)redhat.com are ptrace_attach-shift-sendsigstop-into-ptrace_set_stopped.patch

10 months, 3 weeks

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[merged mm-hotfixes-stable] getrusage-use-sig-stats_lock-rather-than-lock_task_sighand.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: getrusage: use sig->stats_lock rather than lock_task_sighand() has been removed from the -mm tree. Its filename was getrusage-use-sig-stats_lock-rather-than-lock_task_sighand.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Oleg Nesterov <oleg(a)redhat.com> Subject: getrusage: use sig->stats_lock rather than lock_task_sighand() Date: Mon, 22 Jan 2024 16:50:53 +0100 lock_task_sighand() can trigger a hard lockup. If NR_CPUS threads call getrusage() at the same time and the process has NR_THREADS, spin_lock_irq will spin with irqs disabled O(NR_CPUS * NR_THREADS) time. Change getrusage() to use sig->stats_lock, it was specifically designed for this type of use. This way it runs lockless in the likely case. TODO: - Change do_task_stat() to use sig->stats_lock too, then we can remove spin_lock_irq(siglock) in wait_task_zombie(). - Turn sig->stats_lock into seqcount_rwlock_t, this way the readers in the slow mode won't exclude each other. See https://lore.kernel.org/all/20230913154907.GA26210@redhat.com/ - stats_lock has to disable irqs because ->siglock can be taken in irq context, it would be very nice to change __exit_signal() to avoid the siglock->stats_lock dependency. Link: https://lkml.kernel.org/r/20240122155053.GA26214@redhat.com Signed-off-by: Oleg Nesterov <oleg(a)redhat.com> Reported-by: Dylan Hatch <dylanbhatch(a)google.com> Tested-by: Dylan Hatch <dylanbhatch(a)google.com> Cc: Eric W. Biederman <ebiederm(a)xmission.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- kernel/sys.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) --- a/kernel/sys.c~getrusage-use-sig-stats_lock-rather-than-lock_task_sighand +++ a/kernel/sys.c @@ -1788,7 +1788,9 @@ void getrusage(struct task_struct *p, in unsigned long maxrss; struct mm_struct *mm; struct signal_struct *sig = p->signal; + unsigned int seq = 0; +retry: memset(r, 0, sizeof(*r)); utime = stime = 0; maxrss = 0; @@ -1800,8 +1802,7 @@ void getrusage(struct task_struct *p, in goto out_thread; } - if (!lock_task_sighand(p, &flags)) - return; + flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq); switch (who) { case RUSAGE_BOTH: @@ -1829,14 +1830,23 @@ void getrusage(struct task_struct *p, in r->ru_oublock += sig->oublock; if (maxrss < sig->maxrss) maxrss = sig->maxrss; + + rcu_read_lock(); __for_each_thread(sig, t) accumulate_thread_rusage(t, r); + rcu_read_unlock(); + break; default: BUG(); } - unlock_task_sighand(p, &flags); + + if (need_seqretry(&sig->stats_lock, seq)) { + seq = 1; + goto retry; + } + done_seqretry_irqrestore(&sig->stats_lock, seq, flags); if (who == RUSAGE_CHILDREN) goto out_children; _ Patches currently in -mm which might be from oleg(a)redhat.com are ptrace_attach-shift-sendsigstop-into-ptrace_set_stopped.patch

10 months, 3 weeks

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[merged mm-hotfixes-stable] getrusage-move-thread_group_cputime_adjusted-outside-of-lock_task_sighand.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: getrusage: move thread_group_cputime_adjusted() outside of lock_task_sighand() has been removed from the -mm tree. Its filename was getrusage-move-thread_group_cputime_adjusted-outside-of-lock_task_sighand.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Oleg Nesterov <oleg(a)redhat.com> Subject: getrusage: move thread_group_cputime_adjusted() outside of lock_task_sighand() Date: Mon, 22 Jan 2024 16:50:50 +0100 Patch series "getrusage: use sig->stats_lock", v2. This patch (of 2): thread_group_cputime() does its own locking, we can safely shift thread_group_cputime_adjusted() which does another for_each_thread loop outside of ->siglock protected section. This is also preparation for the next patch which changes getrusage() to use stats_lock instead of siglock, thread_group_cputime() takes the same lock. With the current implementation recursive read_seqbegin_or_lock() is fine, thread_group_cputime() can't enter the slow mode if the caller holds stats_lock, yet this looks more safe and better performance-wise. Link: https://lkml.kernel.org/r/20240122155023.GA26169@redhat.com Link: https://lkml.kernel.org/r/20240122155050.GA26205@redhat.com Signed-off-by: Oleg Nesterov <oleg(a)redhat.com> Reported-by: Dylan Hatch <dylanbhatch(a)google.com> Tested-by: Dylan Hatch <dylanbhatch(a)google.com> Cc: Eric W. Biederman <ebiederm(a)xmission.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- kernel/sys.c | 36 ++++++++++++++++++++---------------- 1 file changed, 20 insertions(+), 16 deletions(-) --- a/kernel/sys.c~getrusage-move-thread_group_cputime_adjusted-outside-of-lock_task_sighand +++ a/kernel/sys.c @@ -1785,17 +1785,19 @@ void getrusage(struct task_struct *p, in struct task_struct *t; unsigned long flags; u64 tgutime, tgstime, utime, stime; - unsigned long maxrss = 0; + unsigned long maxrss; + struct mm_struct *mm; struct signal_struct *sig = p->signal; - memset((char *)r, 0, sizeof (*r)); + memset(r, 0, sizeof(*r)); utime = stime = 0; + maxrss = 0; if (who == RUSAGE_THREAD) { task_cputime_adjusted(current, &utime, &stime); accumulate_thread_rusage(p, r); maxrss = sig->maxrss; - goto out; + goto out_thread; } if (!lock_task_sighand(p, &flags)) @@ -1819,9 +1821,6 @@ void getrusage(struct task_struct *p, in fallthrough; case RUSAGE_SELF: - thread_group_cputime_adjusted(p, &tgutime, &tgstime); - utime += tgutime; - stime += tgstime; r->ru_nvcsw += sig->nvcsw; r->ru_nivcsw += sig->nivcsw; r->ru_minflt += sig->min_flt; @@ -1839,19 +1838,24 @@ void getrusage(struct task_struct *p, in } unlock_task_sighand(p, &flags); -out: - r->ru_utime = ns_to_kernel_old_timeval(utime); - r->ru_stime = ns_to_kernel_old_timeval(stime); - - if (who != RUSAGE_CHILDREN) { - struct mm_struct *mm = get_task_mm(p); + if (who == RUSAGE_CHILDREN) + goto out_children; - if (mm) { - setmax_mm_hiwater_rss(&maxrss, mm); - mmput(mm); - } + thread_group_cputime_adjusted(p, &tgutime, &tgstime); + utime += tgutime; + stime += tgstime; + +out_thread: + mm = get_task_mm(p); + if (mm) { + setmax_mm_hiwater_rss(&maxrss, mm); + mmput(mm); } + +out_children: r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ + r->ru_utime = ns_to_kernel_old_timeval(utime); + r->ru_stime = ns_to_kernel_old_timeval(stime); } SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) _ Patches currently in -mm which might be from oleg(a)redhat.com are ptrace_attach-shift-sendsigstop-into-ptrace_set_stopped.patch

10 months, 3 weeks

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[PATCH] ASoC: tas2781: remove unused acpi_subysystem_id

by Gergo Koteles

The acpi_subysystem_id is only written and freed, not read, so unnecessary. Fixes: ef3bcde75d06 ("ASoC: tas2781: Add tas2781 driver") CC: stable(a)vger.kernel.org Signed-off-by: Gergo Koteles <soyer(a)irl.hu> --- include/sound/tas2781.h | 1 - sound/pci/hda/tas2781_hda_i2c.c | 10 ---------- sound/soc/codecs/tas2781-comlib.c | 1 - 3 files changed, 12 deletions(-) diff --git a/include/sound/tas2781.h b/include/sound/tas2781.h index 9aff384941de..99ca3e401fd1 100644 --- a/include/sound/tas2781.h +++ b/include/sound/tas2781.h @@ -103,7 +103,6 @@ struct tasdevice_priv { struct tm tm; enum device_catlog_id catlog_id; - const char *acpi_subsystem_id; unsigned char cal_binaryname[TASDEVICE_MAX_CHANNELS][64]; unsigned char crc8_lkp_tbl[CRC8_TABLE_SIZE]; unsigned char coef_binaryname[64]; diff --git a/sound/pci/hda/tas2781_hda_i2c.c b/sound/pci/hda/tas2781_hda_i2c.c index 1bfb00102a77..02c85084aca5 100644 --- a/sound/pci/hda/tas2781_hda_i2c.c +++ b/sound/pci/hda/tas2781_hda_i2c.c @@ -129,18 +129,8 @@ static int tas2781_read_acpi(struct tasdevice_priv *p, const char *hid) acpi_dev_free_resource_list(&resources); strscpy(p->dev_name, hid, sizeof(p->dev_name)); - physdev = get_device(acpi_get_first_physical_node(adev)); acpi_dev_put(adev); - /* No side-effect to the playback even if subsystem_id is NULL*/ - sub = acpi_get_subsystem_id(ACPI_HANDLE(physdev)); - if (IS_ERR(sub)) - sub = NULL; - - p->acpi_subsystem_id = sub; - - put_device(physdev); - return 0; err: diff --git a/sound/soc/codecs/tas2781-comlib.c b/sound/soc/codecs/tas2781-comlib.c index 5d0e5348b361..3aa81514dad7 100644 --- a/sound/soc/codecs/tas2781-comlib.c +++ b/sound/soc/codecs/tas2781-comlib.c @@ -408,7 +408,6 @@ void tasdevice_remove(struct tasdevice_priv *tas_priv) { if (gpio_is_valid(tas_priv->irq_info.irq_gpio)) gpio_free(tas_priv->irq_info.irq_gpio); - kfree(tas_priv->acpi_subsystem_id); mutex_destroy(&tas_priv->codec_lock); } EXPORT_SYMBOL_GPL(tasdevice_remove); base-commit: 610010737f74482a61896596a0116876ecf9e65c -- 2.43.0

10 months, 3 weeks

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[PATCH AUTOSEL 4.19 1/3] ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()

by Sasha Levin

From: Baokun Li <libaokun1(a)huawei.com> [ Upstream commit 4530b3660d396a646aad91a787b6ab37cf604b53 ] Determine if the group block bitmap is corrupted before using ac_b_ex in ext4_mb_try_best_found() to avoid allocating blocks from a group with a corrupted block bitmap in the following concurrency and making the situation worse. ext4_mb_regular_allocator ext4_lock_group(sb, group) ext4_mb_good_group // check if the group bbitmap is corrupted ext4_mb_complex_scan_group // Scan group gets ac_b_ex but doesn't use it ext4_unlock_group(sb, group) ext4_mark_group_bitmap_corrupted(group) // The block bitmap was corrupted during // the group unlock gap. ext4_mb_try_best_found ext4_lock_group(ac->ac_sb, group) ext4_mb_use_best_found mb_mark_used // Allocating blocks in block bitmap corrupted group Signed-off-by: Baokun Li <libaokun1(a)huawei.com> Reviewed-by: Jan Kara <jack(a)suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-7-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/ext4/mballoc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 8875fac9f958..cf034a38e8ba 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1802,6 +1802,9 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac, return err; ext4_lock_group(ac->ac_sb, group); + if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(e4b->bd_info))) + goto out; + max = mb_find_extent(e4b, ex.fe_start, ex.fe_len, &ex); if (max > 0) { @@ -1809,6 +1812,7 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac, ext4_mb_use_best_found(ac, e4b); } +out: ext4_unlock_group(ac->ac_sb, group); ext4_mb_unload_buddy(e4b); -- 2.43.0

10 months, 3 weeks

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[PATCH AUTOSEL 5.4 1/7] ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()

by Sasha Levin

From: Baokun Li <libaokun1(a)huawei.com> [ Upstream commit 4530b3660d396a646aad91a787b6ab37cf604b53 ] Determine if the group block bitmap is corrupted before using ac_b_ex in ext4_mb_try_best_found() to avoid allocating blocks from a group with a corrupted block bitmap in the following concurrency and making the situation worse. ext4_mb_regular_allocator ext4_lock_group(sb, group) ext4_mb_good_group // check if the group bbitmap is corrupted ext4_mb_complex_scan_group // Scan group gets ac_b_ex but doesn't use it ext4_unlock_group(sb, group) ext4_mark_group_bitmap_corrupted(group) // The block bitmap was corrupted during // the group unlock gap. ext4_mb_try_best_found ext4_lock_group(ac->ac_sb, group) ext4_mb_use_best_found mb_mark_used // Allocating blocks in block bitmap corrupted group Signed-off-by: Baokun Li <libaokun1(a)huawei.com> Reviewed-by: Jan Kara <jack(a)suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-7-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/ext4/mballoc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 9e5aa625ab30..c1af95898aa4 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1802,6 +1802,9 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac, return err; ext4_lock_group(ac->ac_sb, group); + if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(e4b->bd_info))) + goto out; + max = mb_find_extent(e4b, ex.fe_start, ex.fe_len, &ex); if (max > 0) { @@ -1809,6 +1812,7 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac, ext4_mb_use_best_found(ac, e4b); } +out: ext4_unlock_group(ac->ac_sb, group); ext4_mb_unload_buddy(e4b); -- 2.43.0

10 months, 3 weeks

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[PATCH AUTOSEL 5.15 01/23] ext4: avoid dividing by 0 in mb_update_avg_fragment_size() when block bitmap corrupt

by Sasha Levin

From: Baokun Li <libaokun1(a)huawei.com> [ Upstream commit 993bf0f4c393b3667830918f9247438a8f6fdb5b ] Determine if bb_fragments is 0 instead of determining bb_free to eliminate the risk of dividing by zero when the block bitmap is corrupted. Signed-off-by: Baokun Li <libaokun1(a)huawei.com> Reviewed-by: Jan Kara <jack(a)suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-6-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/ext4/mballoc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index e44c28ceb9cd..3df3c3894f7b 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -853,7 +853,7 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp) { struct ext4_sb_info *sbi = EXT4_SB(sb); - if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_free == 0) + if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_fragments == 0) return; write_lock(&sbi->s_mb_rb_lock); -- 2.43.0

10 months, 3 weeks

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[PATCH AUTOSEL 6.1 01/29] ext4: avoid dividing by 0 in mb_update_avg_fragment_size() when block bitmap corrupt

by Sasha Levin

From: Baokun Li <libaokun1(a)huawei.com> [ Upstream commit 993bf0f4c393b3667830918f9247438a8f6fdb5b ] Determine if bb_fragments is 0 instead of determining bb_free to eliminate the risk of dividing by zero when the block bitmap is corrupted. Signed-off-by: Baokun Li <libaokun1(a)huawei.com> Reviewed-by: Jan Kara <jack(a)suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-6-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/ext4/mballoc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 33be702d6e38..779555925029 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -831,7 +831,7 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp) struct ext4_sb_info *sbi = EXT4_SB(sb); int new_order; - if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_free == 0) + if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_fragments == 0) return; new_order = mb_avg_fragment_size_order(sb, -- 2.43.0

10 months, 3 weeks

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[PATCH AUTOSEL 6.6 01/38] ext4: avoid dividing by 0 in mb_update_avg_fragment_size() when block bitmap corrupt

by Sasha Levin

From: Baokun Li <libaokun1(a)huawei.com> [ Upstream commit 993bf0f4c393b3667830918f9247438a8f6fdb5b ] Determine if bb_fragments is 0 instead of determining bb_free to eliminate the risk of dividing by zero when the block bitmap is corrupted. Signed-off-by: Baokun Li <libaokun1(a)huawei.com> Reviewed-by: Jan Kara <jack(a)suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-6-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/ext4/mballoc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 9a4b73485ded..f74a8f144a66 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -841,7 +841,7 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp) struct ext4_sb_info *sbi = EXT4_SB(sb); int new_order; - if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_free == 0) + if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_fragments == 0) return; new_order = mb_avg_fragment_size_order(sb, -- 2.43.0

10 months, 3 weeks

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