January 2025 - Linux-stable-mirror

patch "iio: dac: ad3552r-hs: clear reset status flag" added to char-misc-next

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled iio: dac: ad3552r-hs: clear reset status flag to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. From 012b8276f08a67b9f2e2fd0f35363ae4a75e5267 Mon Sep 17 00:00:00 2001 From: Angelo Dureghello <adureghello(a)baylibre.com> Date: Wed, 8 Jan 2025 18:29:16 +0100 Subject: iio: dac: ad3552r-hs: clear reset status flag Clear reset status flag, to keep error status register clean after reset (ad3552r manual, rev B table 38). Reset error flag was left to 1, so debugging registers, the "Error Status Register" was dirty (0x01). It is important to clear this bit, so if there is any reset event over normal working mode, it is possible to detect it. Fixes: 0b4d9fe58be8 ("iio: dac: ad3552r: add high-speed platform driver") Signed-off-by: Angelo Dureghello <adureghello(a)baylibre.com> Reviewed-by: David Lechner <dlechner(a)baylibre.com> Link: https://patch.msgid.link/20250108-wip-bl-ad3552r-axi-v0-iio-testing-carlos-… Cc: <Stable(a)vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com> --- drivers/iio/dac/ad3552r-hs.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c index 216c634f3eaf..8974df625670 100644 --- a/drivers/iio/dac/ad3552r-hs.c +++ b/drivers/iio/dac/ad3552r-hs.c @@ -329,6 +329,12 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st) dev_info(st->dev, "Chip ID error. Expected 0x%x, Read 0x%x\n", AD3552R_ID, id); + /* Clear reset error flag, see ad3552r manual, rev B table 38. */ + ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS, + AD3552R_MASK_RESET_STATUS, 1); + if (ret) + return ret; + ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_SH_REFERENCE_CONFIG, 0, 1); -- 2.48.1

4 months, 3 weeks

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patch "iio: chemical: bme680: Fix uninitialized variable in" added to char-misc-next

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled iio: chemical: bme680: Fix uninitialized variable in to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. From 20eb1fae4145bc45717aa8a6d05fcd6a64ed856a Mon Sep 17 00:00:00 2001 From: Dan Carpenter <dan.carpenter(a)linaro.org> Date: Wed, 8 Jan 2025 12:37:22 +0300 Subject: iio: chemical: bme680: Fix uninitialized variable in __bme680_read_raw() The bme680_read_temp() function takes a pointer to s16 but we're passing an int pointer to it. This will not work on big endian systems and it also means that the other 16 bits are uninitialized. Pass an s16 type variable. Fixes: f51171ce2236 ("iio: chemical: bme680: Add SCALE and RAW channels") Signed-off-by: Dan Carpenter <dan.carpenter(a)linaro.org> Acked-by: Vasileios Amoiridis <vassilisamir(a)gmail.com> Link: https://patch.msgid.link/4addb68c-853a-49fc-8d40-739e78db5fa1@stanley.mount… Cc: <stable(a)vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com> --- drivers/iio/chemical/bme680_core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/iio/chemical/bme680_core.c b/drivers/iio/chemical/bme680_core.c index d12270409c8a..a2949daf9467 100644 --- a/drivers/iio/chemical/bme680_core.c +++ b/drivers/iio/chemical/bme680_core.c @@ -874,11 +874,11 @@ static int bme680_read_raw(struct iio_dev *indio_dev, case IIO_CHAN_INFO_RAW: switch (chan->type) { case IIO_TEMP: - ret = bme680_read_temp(data, (s16 *)&chan_val); + ret = bme680_read_temp(data, &temp_chan_val); if (ret) return ret; - *val = chan_val; + *val = temp_chan_val; return IIO_VAL_INT; case IIO_PRESSURE: ret = bme680_read_press(data, &chan_val); -- 2.48.1

4 months, 3 weeks

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patch "iio: dac: ad3552r-common: fix ad3541/2r ranges" added to char-misc-next

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled iio: dac: ad3552r-common: fix ad3541/2r ranges to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. From 1e758b613212b6964518a67939535910b5aee831 Mon Sep 17 00:00:00 2001 From: Angelo Dureghello <adureghello(a)baylibre.com> Date: Wed, 8 Jan 2025 18:29:15 +0100 Subject: iio: dac: ad3552r-common: fix ad3541/2r ranges Fix ad3541/2r voltage ranges to be as per ad3542r datasheet, rev. C, table 38 (page 57). The wrong ad354xr ranges was generating erroneous Vpp output. In more details: - fix wrong number of ranges, they are 5 ranges, not 6, - remove non-existent 0-3V range, - adjust order, since ad3552r_find_range() get a wrong index, producing a wrong Vpp as output. Retested all the ranges on real hardware, EVALAD3542RFMCZ: adi,output-range-microvolt (fdt): <(000000) (2500000)>; ok (Rfbx1, switch 10) <(000000) (5000000)>; ok (Rfbx1, switch 10) <(000000) (10000000)>; ok (Rfbx1, switch 10) <(-5000000) (5000000)>; ok (Rfbx2, switch +/- 5) <(-2500000) (7500000)>; ok (Rfbx2, switch -2.5/7.5) Fixes: 8f2b54824b28 ("drivers:iio:dac: Add AD3552R driver support") Signed-off-by: Angelo Dureghello <adureghello(a)baylibre.com> Reviewed-by: David Lechner <dlechner(a)baylibre.com> Link: https://patch.msgid.link/20250108-wip-bl-ad3552r-axi-v0-iio-testing-carlos-… Cc: <Stable(a)vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com> --- drivers/iio/dac/ad3552r-common.c | 5 ++--- drivers/iio/dac/ad3552r.h | 8 +++----- 2 files changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/iio/dac/ad3552r-common.c b/drivers/iio/dac/ad3552r-common.c index 0f495df2e5ce..03e0864f5084 100644 --- a/drivers/iio/dac/ad3552r-common.c +++ b/drivers/iio/dac/ad3552r-common.c @@ -22,11 +22,10 @@ EXPORT_SYMBOL_NS_GPL(ad3552r_ch_ranges, "IIO_AD3552R"); const s32 ad3542r_ch_ranges[AD3542R_MAX_RANGES][2] = { [AD3542R_CH_OUTPUT_RANGE_0__2P5V] = { 0, 2500 }, - [AD3542R_CH_OUTPUT_RANGE_0__3V] = { 0, 3000 }, [AD3542R_CH_OUTPUT_RANGE_0__5V] = { 0, 5000 }, [AD3542R_CH_OUTPUT_RANGE_0__10V] = { 0, 10000 }, - [AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V] = { -2500, 7500 }, - [AD3542R_CH_OUTPUT_RANGE_NEG_5__5V] = { -5000, 5000 } + [AD3542R_CH_OUTPUT_RANGE_NEG_5__5V] = { -5000, 5000 }, + [AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V] = { -2500, 7500 } }; EXPORT_SYMBOL_NS_GPL(ad3542r_ch_ranges, "IIO_AD3552R"); diff --git a/drivers/iio/dac/ad3552r.h b/drivers/iio/dac/ad3552r.h index fd5a3dfd1d1c..4b5581039ae9 100644 --- a/drivers/iio/dac/ad3552r.h +++ b/drivers/iio/dac/ad3552r.h @@ -131,7 +131,7 @@ #define AD3552R_CH1_ACTIVE BIT(1) #define AD3552R_MAX_RANGES 5 -#define AD3542R_MAX_RANGES 6 +#define AD3542R_MAX_RANGES 5 #define AD3552R_QUAD_SPI 2 extern const s32 ad3552r_ch_ranges[AD3552R_MAX_RANGES][2]; @@ -189,16 +189,14 @@ enum ad3552r_ch_vref_select { enum ad3542r_ch_output_range { /* Range from 0 V to 2.5 V. Requires Rfb1x connection */ AD3542R_CH_OUTPUT_RANGE_0__2P5V, - /* Range from 0 V to 3 V. Requires Rfb1x connection */ - AD3542R_CH_OUTPUT_RANGE_0__3V, /* Range from 0 V to 5 V. Requires Rfb1x connection */ AD3542R_CH_OUTPUT_RANGE_0__5V, /* Range from 0 V to 10 V. Requires Rfb2x connection */ AD3542R_CH_OUTPUT_RANGE_0__10V, - /* Range from -2.5 V to 7.5 V. Requires Rfb2x connection */ - AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V, /* Range from -5 V to 5 V. Requires Rfb2x connection */ AD3542R_CH_OUTPUT_RANGE_NEG_5__5V, + /* Range from -2.5 V to 7.5 V. Requires Rfb2x connection */ + AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V, }; enum ad3552r_ch_output_range { -- 2.48.1

4 months, 3 weeks

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[tip: timers/urgent] hrtimers: Handle CPU state correctly on hotplug

by tip-bot2 for Koichiro Den

The following commit has been merged into the timers/urgent branch of tip: Commit-ID: 2f8dea1692eef2b7ba6a256246ed82c365fdc686 Gitweb: https://git.kernel.org/tip/2f8dea1692eef2b7ba6a256246ed82c365fdc686 Author: Koichiro Den <koichiro.den(a)canonical.com> AuthorDate: Fri, 20 Dec 2024 22:44:21 +09:00 Committer: Thomas Gleixner <tglx(a)linutronix.de> CommitterDate: Thu, 16 Jan 2025 13:06:14 +01:00 hrtimers: Handle CPU state correctly on hotplug Consider a scenario where a CPU transitions from CPUHP_ONLINE to halfway through a CPU hotunplug down to CPUHP_HRTIMERS_PREPARE, and then back to CPUHP_ONLINE: Since hrtimers_prepare_cpu() does not run, cpu_base.hres_active remains set to 1 throughout. However, during a CPU unplug operation, the tick and the clockevents are shut down at CPUHP_AP_TICK_DYING. On return to the online state, for instance CFS incorrectly assumes that the hrtick is already active, and the chance of the clockevent device to transition to oneshot mode is also lost forever for the CPU, unless it goes back to a lower state than CPUHP_HRTIMERS_PREPARE once. This round-trip reveals another issue; cpu_base.online is not set to 1 after the transition, which appears as a WARN_ON_ONCE in enqueue_hrtimer(). Aside of that, the bulk of the per CPU state is not reset either, which means there are dangling pointers in the worst case. Address this by adding a corresponding startup() callback, which resets the stale per CPU state and sets the online flag. [ tglx: Make the new callback unconditionally available, remove the online modification in the prepare() callback and clear the remaining state in the starting callback instead of the prepare callback ] Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier") Signed-off-by: Koichiro Den <koichiro.den(a)canonical.com> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: stable(a)vger.kernel.org Link: https://lore.kernel.org/all/20241220134421.3809834-1-koichiro.den@canonical… --- include/linux/hrtimer.h | 1 + kernel/cpu.c | 2 +- kernel/time/hrtimer.c | 11 ++++++++++- 3 files changed, 12 insertions(+), 2 deletions(-) diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 7ef5f7e..f7bfdcf 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -386,6 +386,7 @@ extern void __init hrtimers_init(void); extern void sysrq_timer_list_show(void); int hrtimers_prepare_cpu(unsigned int cpu); +int hrtimers_cpu_starting(unsigned int cpu); #ifdef CONFIG_HOTPLUG_CPU int hrtimers_cpu_dying(unsigned int cpu); #else diff --git a/kernel/cpu.c b/kernel/cpu.c index b605334..0509a97 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -2179,7 +2179,7 @@ static struct cpuhp_step cpuhp_hp_states[] = { }, [CPUHP_AP_HRTIMERS_DYING] = { .name = "hrtimers:dying", - .startup.single = NULL, + .startup.single = hrtimers_cpu_starting, .teardown.single = hrtimers_cpu_dying, }, [CPUHP_AP_TICK_DYING] = { diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 80fe374..030426c 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -2202,6 +2202,15 @@ int hrtimers_prepare_cpu(unsigned int cpu) } cpu_base->cpu = cpu; + hrtimer_cpu_base_init_expiry_lock(cpu_base); + return 0; +} + +int hrtimers_cpu_starting(unsigned int cpu) +{ + struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); + + /* Clear out any left over state from a CPU down operation */ cpu_base->active_bases = 0; cpu_base->hres_active = 0; cpu_base->hang_detected = 0; @@ -2210,7 +2219,6 @@ int hrtimers_prepare_cpu(unsigned int cpu) cpu_base->expires_next = KTIME_MAX; cpu_base->softirq_expires_next = KTIME_MAX; cpu_base->online = 1; - hrtimer_cpu_base_init_expiry_lock(cpu_base); return 0; } @@ -2286,5 +2294,6 @@ int hrtimers_cpu_dying(unsigned int dying_cpu) void __init hrtimers_init(void) { hrtimers_prepare_cpu(smp_processor_id()); + hrtimers_cpu_starting(smp_processor_id()); open_softirq(HRTIMER_SOFTIRQ, hrtimer_run_softirq); }

4 months, 3 weeks

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[tip: timers/urgent] timers/migration: Fix another race between hotplug and idle entry/exit

by tip-bot2 for Frederic Weisbecker

The following commit has been merged into the timers/urgent branch of tip: Commit-ID: b729cc1ec21a5899b7879ccfbe1786664928d597 Gitweb: https://git.kernel.org/tip/b729cc1ec21a5899b7879ccfbe1786664928d597 Author: Frederic Weisbecker <frederic(a)kernel.org> AuthorDate: Wed, 15 Jan 2025 00:15:04 +01:00 Committer: Thomas Gleixner <tglx(a)linutronix.de> CommitterDate: Thu, 16 Jan 2025 12:47:11 +01:00 timers/migration: Fix another race between hotplug and idle entry/exit Commit 10a0e6f3d3db ("timers/migration: Move hierarchy setup into cpuhotplug prepare callback") fixed a race between idle exit and CPU hotplug up leading to a wrong "0" value migrator assigned to the top level. However there is still a situation that remains unhandled: [GRP0:0] migrator = TMIGR_NONE active = NONE groupmask = 0 / \ \ 0 1 2..7 idle idle idle 0) The system is fully idle. [GRP0:0] migrator = CPU 0 active = CPU 0 groupmask = 0 / \ \ 0 1 2..7 active idle idle 1) CPU 0 is activating. It has done the cmpxchg on the top's ->migr_state but it hasn't yet returned to __walk_groups(). [GRP0:0] migrator = CPU 0 active = CPU 0, CPU 1 groupmask = 0 / \ \ 0 1 2..7 active active idle 2) CPU 1 is activating. CPU 0 stays the migrator (still stuck in __walk_groups(), delayed by #VMEXIT for example). [GRP1:0] migrator = TMIGR_NONE active = NONE groupmask = 0 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 2 groupmask = 1 / \ \ 0 1 2..7 8 active active idle !online 3) CPU 8 is preparing to boot. CPUHP_TMIGR_PREPARE is being ran by CPU 1 which has created the GRP0:1 and the new top GRP1:0 connected to GRP0:1 and GRP0:0. The groupmask of GRP0:0 is now 2. CPU 1 hasn't yet propagated its activation up to GRP1:0. [GRP1:0] migrator = 0 (!!!) active = NONE groupmask = 0 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 2 groupmask = 1 / \ \ 0 1 2..7 8 active active idle !online 4) CPU 0 finally resumed after its #VMEXIT. It's in __walk_groups() returning from tmigr_cpu_active(). The new top GRP1:0 is visible and fetched but the freshly updated groupmask of GRP0:0 may not be visible due to lack of ordering! As a result tmigr_active_up() is called to GRP0:0 with a child's groupmask of "0". This buggy "0" groupmask then becomes the migrator for GRP1:0 forever. As a result, timers on a fully idle system get ignored. One possible fix would be to define TMIGR_NONE as "0" so that such a race would have no effect. And after all TMIGR_NONE doesn't need to be anything else. However this would leave an uncomfortable state machine where gears happen not to break by chance but are vulnerable to future modifications. Keep TMIGR_NONE as is instead and pre-initialize to "1" the groupmask of any newly created top level. This groupmask is guaranteed to be visible upon fetching the corresponding group for the 1st time: _ By the upcoming CPU thanks to CPU hotplug synchronization between the control CPU (BP) and the booting one (AP). _ By the control CPU since the groupmask and parent pointers are initialized locally. _ By all CPUs belonging to the same group than the control CPU because they must wait for it to ever become idle before needing to walk to the new top. The cmpcxhg() on ->migr_state then makes sure its groupmask is visible. With this pre-initialization, it is guaranteed that if a future top level is linked to an old one, it is walked through with a valid groupmask. Fixes: 10a0e6f3d3db ("timers/migration: Move hierarchy setup into cpuhotplug prepare callback") Signed-off-by: Frederic Weisbecker <frederic(a)kernel.org> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: stable(a)vger.kernel.org Link: https://lore.kernel.org/all/20250114231507.21672-2-frederic@kernel.org --- kernel/time/timer_migration.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/kernel/time/timer_migration.c b/kernel/time/timer_migration.c index 8d57f76..c8a8ea2 100644 --- a/kernel/time/timer_migration.c +++ b/kernel/time/timer_migration.c @@ -1487,6 +1487,21 @@ static void tmigr_init_group(struct tmigr_group *group, unsigned int lvl, s.seq = 0; atomic_set(&group->migr_state, s.state); + /* + * If this is a new top-level, prepare its groupmask in advance. + * This avoids accidents where yet another new top-level is + * created in the future and made visible before the current groupmask. + */ + if (list_empty(&tmigr_level_list[lvl])) { + group->groupmask = BIT(0); + /* + * The previous top level has prepared its groupmask already, + * simply account it as the first child. + */ + if (lvl > 0) + group->num_children = 1; + } + timerqueue_init_head(&group->events); timerqueue_init(&group->groupevt.nextevt); group->groupevt.nextevt.expires = KTIME_MAX; @@ -1550,8 +1565,20 @@ static void tmigr_connect_child_parent(struct tmigr_group *child, raw_spin_lock_irq(&child->lock); raw_spin_lock_nested(&parent->lock, SINGLE_DEPTH_NESTING); + if (activate) { + /* + * @child is the old top and @parent the new one. In this + * case groupmask is pre-initialized and @child already + * accounted, along with its new sibling corresponding to the + * CPU going up. + */ + WARN_ON_ONCE(child->groupmask != BIT(0) || parent->num_children != 2); + } else { + /* Adding @child for the CPU going up to @parent. */ + child->groupmask = BIT(parent->num_children++); + } + child->parent = parent; - child->groupmask = BIT(parent->num_children++); raw_spin_unlock(&parent->lock); raw_spin_unlock_irq(&child->lock);

4 months, 3 weeks

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[tip: timers/urgent] timers/migration: Enforce group initialization visibility to tree walkers

by tip-bot2 for Frederic Weisbecker

The following commit has been merged into the timers/urgent branch of tip: Commit-ID: de3ced72a79280fefd680e5e101d8b9f03cfa1d7 Gitweb: https://git.kernel.org/tip/de3ced72a79280fefd680e5e101d8b9f03cfa1d7 Author: Frederic Weisbecker <frederic(a)kernel.org> AuthorDate: Wed, 15 Jan 2025 00:15:05 +01:00 Committer: Thomas Gleixner <tglx(a)linutronix.de> CommitterDate: Thu, 16 Jan 2025 12:47:11 +01:00 timers/migration: Enforce group initialization visibility to tree walkers Commit 2522c84db513 ("timers/migration: Fix another race between hotplug and idle entry/exit") fixed yet another race between idle exit and CPU hotplug up leading to a wrong "0" value migrator assigned to the top level. However there is yet another situation that remains unhandled: [GRP0:0] migrator = TMIGR_NONE active = NONE groupmask = 1 / \ \ 0 1 2..7 idle idle idle 0) The system is fully idle. [GRP0:0] migrator = CPU 0 active = CPU 0 groupmask = 1 / \ \ 0 1 2..7 active idle idle 1) CPU 0 is activating. It has done the cmpxchg on the top's ->migr_state but it hasn't yet returned to __walk_groups(). [GRP0:0] migrator = CPU 0 active = CPU 0, CPU 1 groupmask = 1 / \ \ 0 1 2..7 active active idle 2) CPU 1 is activating. CPU 0 stays the migrator (still stuck in __walk_groups(), delayed by #VMEXIT for example). [GRP1:0] migrator = TMIGR_NONE active = NONE groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 1 groupmask = 2 / \ \ 0 1 2..7 8 active active idle !online 3) CPU 8 is preparing to boot. CPUHP_TMIGR_PREPARE is being ran by CPU 1 which has created the GRP0:1 and the new top GRP1:0 connected to GRP0:1 and GRP0:0. CPU 1 hasn't yet propagated its activation up to GRP1:0. [GRP1:0] migrator = GRP0:0 active = GRP0:0 groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 1 groupmask = 2 / \ \ 0 1 2..7 8 active active idle !online 4) CPU 0 finally resumed after its #VMEXIT. It's in __walk_groups() returning from tmigr_cpu_active(). The new top GRP1:0 is visible and fetched and the pre-initialized groupmask of GRP0:0 is also visible. As a result tmigr_active_up() is called to GRP1:0 with GRP0:0 as active and migrator. CPU 0 is returning to __walk_groups() but suffers again a #VMEXIT. [GRP1:0] migrator = GRP0:0 active = GRP0:0 groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 1 groupmask = 2 / \ \ 0 1 2..7 8 active active idle !online 5) CPU 1 propagates its activation of GRP0:0 to GRP1:0. This has no effect since CPU 0 did it already. [GRP1:0] migrator = GRP0:0 active = GRP0:0, GRP0:1 groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = CPU 8 active = CPU 0, CPU1 active = CPU 8 groupmask = 1 groupmask = 2 / \ \ \ 0 1 2..7 8 active active idle active 6) CPU 1 links CPU 8 to its group. CPU 8 boots and goes through CPUHP_AP_TMIGR_ONLINE which propagates activation. [GRP2:0] migrator = TMIGR_NONE active = NONE groupmask = 1 / \ [GRP1:0] [GRP1:1] migrator = GRP0:0 migrator = TMIGR_NONE active = GRP0:0, GRP0:1 active = NONE groupmask = 1 groupmask = 2 / \ [GRP0:0] [GRP0:1] [GRP0:2] migrator = CPU 0 migrator = CPU 8 migrator = TMIGR_NONE active = CPU 0, CPU1 active = CPU 8 active = NONE groupmask = 1 groupmask = 2 groupmask = 0 / \ \ \ 0 1 2..7 8 64 active active idle active !online 7) CPU 64 is booting. CPUHP_TMIGR_PREPARE is being ran by CPU 1 which has created the GRP1:1, GRP0:2 and the new top GRP2:0 connected to GRP1:1 and GRP1:0. CPU 1 hasn't yet propagated its activation up to GRP2:0. [GRP2:0] migrator = 0 (!!!) active = NONE groupmask = 1 / \ [GRP1:0] [GRP1:1] migrator = GRP0:0 migrator = TMIGR_NONE active = GRP0:0, GRP0:1 active = NONE groupmask = 1 groupmask = 2 / \ [GRP0:0] [GRP0:1] [GRP0:2] migrator = CPU 0 migrator = CPU 8 migrator = TMIGR_NONE active = CPU 0, CPU1 active = CPU 8 active = NONE groupmask = 1 groupmask = 2 groupmask = 0 / \ \ \ 0 1 2..7 8 64 active active idle active !online 8) CPU 0 finally resumed after its #VMEXIT. It's in __walk_groups() returning from tmigr_cpu_active(). The new top GRP2:0 is visible and fetched but the pre-initialized groupmask of GRP1:0 is not because no ordering made its initialization visible. As a result tmigr_active_up() may be called to GRP2:0 with a "0" child's groumask. Leaving the timers ignored for ever when the system is fully idle. The race is highly theoretical and perhaps impossible in practice but the groupmask of the child is not the only concern here as the whole initialization of the child is not guaranteed to be visible to any tree walker racing against hotplug (idle entry/exit, remote handling, etc...). Although the current code layout seem to be resilient to such hazards, this doesn't tell much about the future. Fix this with enforcing address dependency between group initialization and the write/read to the group's parent's pointer. Fortunately that doesn't involve any barrier addition in the fast paths. Fixes: 10a0e6f3d3db ("timers/migration: Move hierarchy setup into cpuhotplug prepare callback") Signed-off-by: Frederic Weisbecker <frederic(a)kernel.org> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: stable(a)vger.kernel.org Link: https://lore.kernel.org/all/20250114231507.21672-3-frederic@kernel.org --- kernel/time/timer_migration.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/kernel/time/timer_migration.c b/kernel/time/timer_migration.c index c8a8ea2..371a62a 100644 --- a/kernel/time/timer_migration.c +++ b/kernel/time/timer_migration.c @@ -534,8 +534,13 @@ static void __walk_groups(up_f up, struct tmigr_walk *data, break; child = group; - group = group->parent; + /* + * Pairs with the store release on group connection + * to make sure group initialization is visible. + */ + group = READ_ONCE(group->parent); data->childmask = child->groupmask; + WARN_ON_ONCE(!data->childmask); } while (group); } @@ -1578,7 +1583,12 @@ static void tmigr_connect_child_parent(struct tmigr_group *child, child->groupmask = BIT(parent->num_children++); } - child->parent = parent; + /* + * Make sure parent initialization is visible before publishing it to a + * racing CPU entering/exiting idle. This RELEASE barrier enforces an + * address dependency that pairs with the READ_ONCE() in __walk_groups(). + */ + smp_store_release(&child->parent, parent); raw_spin_unlock(&parent->lock); raw_spin_unlock_irq(&child->lock);

4 months, 3 weeks

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[PATCH v2 6/7] ima: Discard files opened with O_PATH

by Roberto Sassu

From: Roberto Sassu <roberto.sassu(a)huawei.com> According to man open.2, files opened with O_PATH are not really opened. The obtained file descriptor is used to indicate a location in the filesystem tree and to perform operations that act purely at the file descriptor level. Thus, ignore open() syscalls with O_PATH, since IMA cares about file data. Cc: stable(a)vger.kernel.org # v2.6.39.x Fixes: 1abf0c718f15a ("New kind of open files - "location only".") Signed-off-by: Roberto Sassu <roberto.sassu(a)huawei.com> --- security/integrity/ima/ima_main.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 50b37420ea2c..712c3a522e6c 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -202,7 +202,8 @@ static void ima_file_free(struct file *file) struct inode *inode = file_inode(file); struct ima_iint_cache *iint; - if (!ima_policy_flag || !S_ISREG(inode->i_mode)) + if (!ima_policy_flag || !S_ISREG(inode->i_mode) || + (file->f_flags & O_PATH)) return; iint = ima_iint_find(inode); @@ -232,7 +233,8 @@ static int process_measurement(struct file *file, const struct cred *cred, enum hash_algo hash_algo; unsigned int allowed_algos = 0; - if (!ima_policy_flag || !S_ISREG(inode->i_mode)) + if (!ima_policy_flag || !S_ISREG(inode->i_mode) || + (file->f_flags & O_PATH)) return 0; /* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action -- 2.47.0.118.gfd3785337b

4 months, 3 weeks

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[PATCH 1/1] usb: typec: tcpm: set SRC_SEND_CAPABILITIES timeout to PD_T_SENDER_RESPONSE

by joswang

From: Jos Wang <joswang(a)lenovo.com> As PD2.0 spec ("8.3.3.2.3 PE_SRC_Send_Capabilities state"), after the Source receives the GoodCRC Message from the Sink in response to the Source_Capabilities message, it should start the SenderResponseTimer, after the timer times out, the state machine transitions to the HARD_RESET state. Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)") Cc: stable(a)vger.kernel.org Signed-off-by: Jos Wang <joswang(a)lenovo.com> --- drivers/usb/typec/tcpm/tcpm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 460dbde9fe22..57fae1118ac9 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -4821,7 +4821,7 @@ static void run_state_machine(struct tcpm_port *port) port->caps_count = 0; port->pd_capable = true; tcpm_set_state_cond(port, SRC_SEND_CAPABILITIES_TIMEOUT, - PD_T_SEND_SOURCE_CAP); + PD_T_SENDER_RESPONSE); } break; case SRC_SEND_CAPABILITIES_TIMEOUT: -- 2.17.1

4 months, 3 weeks

3
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[tip: timers/urgent] timers/migration: Fix another race between hotplug and idle entry/exit

by tip-bot2 for Frederic Weisbecker

The following commit has been merged into the timers/urgent branch of tip: Commit-ID: de7cf2540a9b69e8e057ac25aa3c6b33fca81978 Gitweb: https://git.kernel.org/tip/de7cf2540a9b69e8e057ac25aa3c6b33fca81978 Author: Frederic Weisbecker <frederic(a)kernel.org> AuthorDate: Wed, 15 Jan 2025 00:15:04 +01:00 Committer: Thomas Gleixner <tglx(a)linutronix.de> CommitterDate: Thu, 16 Jan 2025 12:04:47 +01:00 timers/migration: Fix another race between hotplug and idle entry/exit Commit 10a0e6f3d3db ("timers/migration: Move hierarchy setup into cpuhotplug prepare callback") fixed a race between idle exit and CPU hotplug up leading to a wrong "0" value migrator assigned to the top level. However there is still a situation that remains unhandled: [GRP0:0] migrator = TMIGR_NONE active = NONE groupmask = 0 / \ \ 0 1 2..7 idle idle idle 0) The system is fully idle. [GRP0:0] migrator = CPU 0 active = CPU 0 groupmask = 0 / \ \ 0 1 2..7 active idle idle 1) CPU 0 is activating. It has done the cmpxchg on the top's ->migr_state but it hasn't yet returned to __walk_groups(). [GRP0:0] migrator = CPU 0 active = CPU 0, CPU 1 groupmask = 0 / \ \ 0 1 2..7 active active idle 2) CPU 1 is activating. CPU 0 stays the migrator (still stuck in __walk_groups(), delayed by #VMEXIT for example). [GRP1:0] migrator = TMIGR_NONE active = NONE groupmask = 0 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 2 groupmask = 1 / \ \ 0 1 2..7 8 active active idle !online 3) CPU 8 is preparing to boot. CPUHP_TMIGR_PREPARE is being ran by CPU 1 which has created the GRP0:1 and the new top GRP1:0 connected to GRP0:1 and GRP0:0. The groupmask of GRP0:0 is now 2. CPU 1 hasn't yet propagated its activation up to GRP1:0. [GRP1:0] migrator = 0 (!!!) active = NONE groupmask = 0 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 2 groupmask = 1 / \ \ 0 1 2..7 8 active active idle !online 4) CPU 0 finally resumed after its #VMEXIT. It's in __walk_groups() returning from tmigr_cpu_active(). The new top GRP1:0 is visible and fetched but the freshly updated groupmask of GRP0:0 may not be visible due to lack of ordering! As a result tmigr_active_up() is called to GRP0:0 with a child's groupmask of "0". This buggy "0" groupmask then becomes the migrator for GRP1:0 forever. As a result, timers on a fully idle system get ignored. One possible fix would be to define TMIGR_NONE as "0" so that such a race would have no effect. And after all TMIGR_NONE doesn't need to be anything else. However this would leave an uncomfortable state machine where gears happen not to break by chance but are vulnerable to future modifications. Keep TMIGR_NONE as is instead and pre-initialize to "1" the groupmask of any newly created top level. This groupmask is guaranteed to be visible upon fetching the corresponding group for the 1st time: _ By the upcoming CPU thanks to CPU hotplug synchronization between the control CPU (BP) and the booting one (AP). _ By the control CPU since the groupmask and parent pointers are initialized locally. _ By all CPUs belonging to the same group than the control CPU because they must wait for it to ever become idle before needing to walk to the new top. The cmpcxhg() on ->migr_state then makes sure its groupmask is visible. With this pre-initialization, it is guaranteed that if a future top level is linked to an old one, it is walked through with a valid groupmask. Fixes: 10a0e6f3d3db ("timers/migration: Move hierarchy setup into cpuhotplug prepare callback") Signed-off-by: Frederic Weisbecker <frederic(a)kernel.org> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: stable(a)vger.kernel.org Link: https://lore.kernel.org/all/20250114231507.21672-2-frederic@kernel.org --- kernel/time/timer_migration.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/kernel/time/timer_migration.c b/kernel/time/timer_migration.c index 8d57f76..c8a8ea2 100644 --- a/kernel/time/timer_migration.c +++ b/kernel/time/timer_migration.c @@ -1487,6 +1487,21 @@ static void tmigr_init_group(struct tmigr_group *group, unsigned int lvl, s.seq = 0; atomic_set(&group->migr_state, s.state); + /* + * If this is a new top-level, prepare its groupmask in advance. + * This avoids accidents where yet another new top-level is + * created in the future and made visible before the current groupmask. + */ + if (list_empty(&tmigr_level_list[lvl])) { + group->groupmask = BIT(0); + /* + * The previous top level has prepared its groupmask already, + * simply account it as the first child. + */ + if (lvl > 0) + group->num_children = 1; + } + timerqueue_init_head(&group->events); timerqueue_init(&group->groupevt.nextevt); group->groupevt.nextevt.expires = KTIME_MAX; @@ -1550,8 +1565,20 @@ static void tmigr_connect_child_parent(struct tmigr_group *child, raw_spin_lock_irq(&child->lock); raw_spin_lock_nested(&parent->lock, SINGLE_DEPTH_NESTING); + if (activate) { + /* + * @child is the old top and @parent the new one. In this + * case groupmask is pre-initialized and @child already + * accounted, along with its new sibling corresponding to the + * CPU going up. + */ + WARN_ON_ONCE(child->groupmask != BIT(0) || parent->num_children != 2); + } else { + /* Adding @child for the CPU going up to @parent. */ + child->groupmask = BIT(parent->num_children++); + } + child->parent = parent; - child->groupmask = BIT(parent->num_children++); raw_spin_unlock(&parent->lock); raw_spin_unlock_irq(&child->lock);

4 months, 3 weeks

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[tip: timers/urgent] timers/migration: Enforce group initialization visibility to tree walkers

by tip-bot2 for Frederic Weisbecker

The following commit has been merged into the timers/urgent branch of tip: Commit-ID: 4a6e60740a304765285446aa260f88b7c5e51c1b Gitweb: https://git.kernel.org/tip/4a6e60740a304765285446aa260f88b7c5e51c1b Author: Frederic Weisbecker <frederic(a)kernel.org> AuthorDate: Wed, 15 Jan 2025 00:15:05 +01:00 Committer: Thomas Gleixner <tglx(a)linutronix.de> CommitterDate: Thu, 16 Jan 2025 12:04:47 +01:00 timers/migration: Enforce group initialization visibility to tree walkers Commit 2522c84db513 ("timers/migration: Fix another race between hotplug and idle entry/exit") fixed yet another race between idle exit and CPU hotplug up leading to a wrong "0" value migrator assigned to the top level. However there is yet another situation that remains unhandled: [GRP0:0] migrator = TMIGR_NONE active = NONE groupmask = 1 / \ \ 0 1 2..7 idle idle idle 0) The system is fully idle. [GRP0:0] migrator = CPU 0 active = CPU 0 groupmask = 1 / \ \ 0 1 2..7 active idle idle 1) CPU 0 is activating. It has done the cmpxchg on the top's ->migr_state but it hasn't yet returned to __walk_groups(). [GRP0:0] migrator = CPU 0 active = CPU 0, CPU 1 groupmask = 1 / \ \ 0 1 2..7 active active idle 2) CPU 1 is activating. CPU 0 stays the migrator (still stuck in __walk_groups(), delayed by #VMEXIT for example). [GRP1:0] migrator = TMIGR_NONE active = NONE groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 1 groupmask = 2 / \ \ 0 1 2..7 8 active active idle !online 3) CPU 8 is preparing to boot. CPUHP_TMIGR_PREPARE is being ran by CPU 1 which has created the GRP0:1 and the new top GRP1:0 connected to GRP0:1 and GRP0:0. CPU 1 hasn't yet propagated its activation up to GRP1:0. [GRP1:0] migrator = GRP0:0 active = GRP0:0 groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 1 groupmask = 2 / \ \ 0 1 2..7 8 active active idle !online 4) CPU 0 finally resumed after its #VMEXIT. It's in __walk_groups() returning from tmigr_cpu_active(). The new top GRP1:0 is visible and fetched and the pre-initialized groupmask of GRP0:0 is also visible. As a result tmigr_active_up() is called to GRP1:0 with GRP0:0 as active and migrator. CPU 0 is returning to __walk_groups() but suffers again a #VMEXIT. [GRP1:0] migrator = GRP0:0 active = GRP0:0 groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = TMIGR_NONE active = CPU 0, CPU1 active = NONE groupmask = 1 groupmask = 2 / \ \ 0 1 2..7 8 active active idle !online 5) CPU 1 propagates its activation of GRP0:0 to GRP1:0. This has no effect since CPU 0 did it already. [GRP1:0] migrator = GRP0:0 active = GRP0:0, GRP0:1 groupmask = 1 / \ [GRP0:0] [GRP0:1] migrator = CPU 0 migrator = CPU 8 active = CPU 0, CPU1 active = CPU 8 groupmask = 1 groupmask = 2 / \ \ \ 0 1 2..7 8 active active idle active 6) CPU 1 links CPU 8 to its group. CPU 8 boots and goes through CPUHP_AP_TMIGR_ONLINE which propagates activation. [GRP2:0] migrator = TMIGR_NONE active = NONE groupmask = 1 / \ [GRP1:0] [GRP1:1] migrator = GRP0:0 migrator = TMIGR_NONE active = GRP0:0, GRP0:1 active = NONE groupmask = 1 groupmask = 2 / \ [GRP0:0] [GRP0:1] [GRP0:2] migrator = CPU 0 migrator = CPU 8 migrator = TMIGR_NONE active = CPU 0, CPU1 active = CPU 8 active = NONE groupmask = 1 groupmask = 2 groupmask = 0 / \ \ \ 0 1 2..7 8 64 active active idle active !online 7) CPU 64 is booting. CPUHP_TMIGR_PREPARE is being ran by CPU 1 which has created the GRP1:1, GRP0:2 and the new top GRP2:0 connected to GRP1:1 and GRP1:0. CPU 1 hasn't yet propagated its activation up to GRP2:0. [GRP2:0] migrator = 0 (!!!) active = NONE groupmask = 1 / \ [GRP1:0] [GRP1:1] migrator = GRP0:0 migrator = TMIGR_NONE active = GRP0:0, GRP0:1 active = NONE groupmask = 1 groupmask = 2 / \ [GRP0:0] [GRP0:1] [GRP0:2] migrator = CPU 0 migrator = CPU 8 migrator = TMIGR_NONE active = CPU 0, CPU1 active = CPU 8 active = NONE groupmask = 1 groupmask = 2 groupmask = 0 / \ \ \ 0 1 2..7 8 64 active active idle active !online 8) CPU 0 finally resumed after its #VMEXIT. It's in __walk_groups() returning from tmigr_cpu_active(). The new top GRP2:0 is visible and fetched but the pre-initialized groupmask of GRP1:0 is not because no ordering made its initialization visible. As a result tmigr_active_up() may be called to GRP2:0 with a "0" child's groumask. Leaving the timers ignored for ever when the system is fully idle. The race is highly theoretical and perhaps impossible in practice but the groupmask of the child is not the only concern here as the whole initialization of the child is not guaranteed to be visible to any tree walker racing against hotplug (idle entry/exit, remote handling, etc...). Although the current code layout seem to be resilient to such hazards, this doesn't tell much about the future. Fix this with enforcing address dependency between group initialization and the write/read to the group's parent's pointer. Fortunately that doesn't involve any barrier addition in the fast paths. Fixes: 10a0e6f3d3db ("timers/migration: Move hierarchy setup into cpuhotplug prepare callback") Signed-off-by: Frederic Weisbecker <frederic(a)kernel.org> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: stable(a)vger.kernel.org Link: https://lore.kernel.org/all/20250114231507.21672-3-frederic@kernel.org --- kernel/time/timer_migration.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/kernel/time/timer_migration.c b/kernel/time/timer_migration.c index c8a8ea2..371a62a 100644 --- a/kernel/time/timer_migration.c +++ b/kernel/time/timer_migration.c @@ -534,8 +534,13 @@ static void __walk_groups(up_f up, struct tmigr_walk *data, break; child = group; - group = group->parent; + /* + * Pairs with the store release on group connection + * to make sure group initialization is visible. + */ + group = READ_ONCE(group->parent); data->childmask = child->groupmask; + WARN_ON_ONCE(!data->childmask); } while (group); } @@ -1578,7 +1583,12 @@ static void tmigr_connect_child_parent(struct tmigr_group *child, child->groupmask = BIT(parent->num_children++); } - child->parent = parent; + /* + * Make sure parent initialization is visible before publishing it to a + * racing CPU entering/exiting idle. This RELEASE barrier enforces an + * address dependency that pairs with the READ_ONCE() in __walk_groups(). + */ + smp_store_release(&child->parent, parent); raw_spin_unlock(&parent->lock); raw_spin_unlock_irq(&child->lock);

4 months, 3 weeks

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