November 2024 - Linux-stable-mirror

[PATCH V4] mm/gup: Clear the LRU flag of a page before adding to LRU batch

by yangge1116＠126.com

From: yangge <yangge1116(a)126.com> If a large number of CMA memory are configured in system (for example, the CMA memory accounts for 50% of the system memory), starting a virtual virtual machine with device passthrough, it will call pin_user_pages_remote(..., FOLL_LONGTERM, ...) to pin memory. Normally if a page is present and in CMA area, pin_user_pages_remote() will migrate the page from CMA area to non-CMA area because of FOLL_LONGTERM flag. But the current code will cause the migration failure due to unexpected page refcounts, and eventually cause the virtual machine fail to start. If a page is added in LRU batch, its refcount increases one, remove the page from LRU batch decreases one. Page migration requires the page is not referenced by others except page mapping. Before migrating a page, we should try to drain the page from LRU batch in case the page is in it, however, folio_test_lru() is not sufficient to tell whether the page is in LRU batch or not, if the page is in LRU batch, the migration will fail. To solve the problem above, we modify the logic of adding to LRU batch. Before adding a page to LRU batch, we clear the LRU flag of the page so that we can check whether the page is in LRU batch by folio_test_lru(page). It's quite valuable, because likely we don't want to blindly drain the LRU batch simply because there is some unexpected reference on a page, as described above. This change makes the LRU flag of a page invisible for longer, which may impact some programs. For example, as long as a page is on a LRU batch, we cannot isolate it, and we cannot check if it's an LRU page. Further, a page can now only be on exactly one LRU batch. This doesn't seem to matter much, because a new page is allocated from buddy and added to the lru batch, or be isolated, it's LRU flag may also be invisible for a long time. Fixes: 9a4e9f3b2d73 ("mm: update get_user_pages_longterm to migrate pages allocated from CMA region") Cc: <stable(a)vger.kernel.org> Signed-off-by: yangge <yangge1116(a)126.com> --- mm/swap.c | 43 +++++++++++++++++++++++++++++++------------ 1 file changed, 31 insertions(+), 12 deletions(-) V4: Adjust commit message according to David's comments V3: Add fixes tag V2: Adjust code and commit message according to David's comments diff --git a/mm/swap.c b/mm/swap.c index dc205bd..9caf6b0 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -211,10 +211,6 @@ static void folio_batch_move_lru(struct folio_batch *fbatch, move_fn_t move_fn) for (i = 0; i < folio_batch_count(fbatch); i++) { struct folio *folio = fbatch->folios[i]; - /* block memcg migration while the folio moves between lru */ - if (move_fn != lru_add_fn && !folio_test_clear_lru(folio)) - continue; - folio_lruvec_relock_irqsave(folio, &lruvec, &flags); move_fn(lruvec, folio); @@ -255,11 +251,16 @@ static void lru_move_tail_fn(struct lruvec *lruvec, struct folio *folio) void folio_rotate_reclaimable(struct folio *folio) { if (!folio_test_locked(folio) && !folio_test_dirty(folio) && - !folio_test_unevictable(folio) && folio_test_lru(folio)) { + !folio_test_unevictable(folio)) { struct folio_batch *fbatch; unsigned long flags; folio_get(folio); + if (!folio_test_clear_lru(folio)) { + folio_put(folio); + return; + } + local_lock_irqsave(&lru_rotate.lock, flags); fbatch = this_cpu_ptr(&lru_rotate.fbatch); folio_batch_add_and_move(fbatch, folio, lru_move_tail_fn); @@ -352,11 +353,15 @@ static void folio_activate_drain(int cpu) void folio_activate(struct folio *folio) { - if (folio_test_lru(folio) && !folio_test_active(folio) && - !folio_test_unevictable(folio)) { + if (!folio_test_active(folio) && !folio_test_unevictable(folio)) { struct folio_batch *fbatch; folio_get(folio); + if (!folio_test_clear_lru(folio)) { + folio_put(folio); + return; + } + local_lock(&cpu_fbatches.lock); fbatch = this_cpu_ptr(&cpu_fbatches.activate); folio_batch_add_and_move(fbatch, folio, folio_activate_fn); @@ -700,6 +705,11 @@ void deactivate_file_folio(struct folio *folio) return; folio_get(folio); + if (!folio_test_clear_lru(folio)) { + folio_put(folio); + return; + } + local_lock(&cpu_fbatches.lock); fbatch = this_cpu_ptr(&cpu_fbatches.lru_deactivate_file); folio_batch_add_and_move(fbatch, folio, lru_deactivate_file_fn); @@ -716,11 +726,16 @@ void deactivate_file_folio(struct folio *folio) */ void folio_deactivate(struct folio *folio) { - if (folio_test_lru(folio) && !folio_test_unevictable(folio) && - (folio_test_active(folio) || lru_gen_enabled())) { + if (!folio_test_unevictable(folio) && (folio_test_active(folio) || + lru_gen_enabled())) { struct folio_batch *fbatch; folio_get(folio); + if (!folio_test_clear_lru(folio)) { + folio_put(folio); + return; + } + local_lock(&cpu_fbatches.lock); fbatch = this_cpu_ptr(&cpu_fbatches.lru_deactivate); folio_batch_add_and_move(fbatch, folio, lru_deactivate_fn); @@ -737,12 +752,16 @@ void folio_deactivate(struct folio *folio) */ void folio_mark_lazyfree(struct folio *folio) { - if (folio_test_lru(folio) && folio_test_anon(folio) && - folio_test_swapbacked(folio) && !folio_test_swapcache(folio) && - !folio_test_unevictable(folio)) { + if (folio_test_anon(folio) && folio_test_swapbacked(folio) && + !folio_test_swapcache(folio) && !folio_test_unevictable(folio)) { struct folio_batch *fbatch; folio_get(folio); + if (!folio_test_clear_lru(folio)) { + folio_put(folio); + return; + } + local_lock(&cpu_fbatches.lock); fbatch = this_cpu_ptr(&cpu_fbatches.lru_lazyfree); folio_batch_add_and_move(fbatch, folio, lru_lazyfree_fn); -- 2.7.4

4 months, 2 weeks

3
9
0 0

[PATCH 1/2] drm/i915: Schedule the HPD poll init work on an unbound workqueue

by Imre Deak

Disabling HPD polling from i915_hpd_poll_init_work() involves probing all display connectors explicitly to account for lost hotplug interrupts. On some platforms (mostly pre-ICL) with HDMI connectors the I2C EDID bit-banging using udelay() triggers in turn the workqueue: i915_hpd_poll_init_work [i915] hogged CPU for >10000us 4 times, consider switching to WQ_UNBOUND warning. Fix the above by scheduling i915_hpd_poll_init_work() on a WQ_UNBOUND workqueue. It's ok to use a system WQ, since i915_hpd_poll_init_work() is properly flushed in intel_hpd_cancel_work(). The connector probing from drm_mode_config::output_poll_work resulting in the same warning is fixed by the next patch. Cc: Tejun Heo <tj(a)kernel.org> Cc: Heiner Kallweit <hkallweit1(a)gmail.com> CC: stable(a)vger.kernel.org # 6.5 Suggested-by: Tejun Heo <tj(a)kernel.org> Suggested-by: Heiner Kallweit <hkallweit1(a)gmail.com> Reported-by: Heiner Kallweit <hkallweit1(a)gmail.com> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9245 Link: https://lore.kernel.org/all/f7e21caa-e98d-e5b5-932a-fe12d27fde9b@gmail.com Signed-off-by: Imre Deak <imre.deak(a)intel.com> --- drivers/gpu/drm/i915/display/intel_hotplug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_hotplug.c b/drivers/gpu/drm/i915/display/intel_hotplug.c index e8562f6f8bb44..accc2fec562a0 100644 --- a/drivers/gpu/drm/i915/display/intel_hotplug.c +++ b/drivers/gpu/drm/i915/display/intel_hotplug.c @@ -774,7 +774,7 @@ void intel_hpd_poll_enable(struct drm_i915_private *dev_priv) * As well, there's no issue if we race here since we always reschedule * this worker anyway */ - queue_work(dev_priv->unordered_wq, + queue_work(system_unbound_wq, &dev_priv->display.hotplug.poll_init_work); } @@ -803,7 +803,7 @@ void intel_hpd_poll_disable(struct drm_i915_private *dev_priv) return; WRITE_ONCE(dev_priv->display.hotplug.poll_enabled, false); - queue_work(dev_priv->unordered_wq, + queue_work(system_unbound_wq, &dev_priv->display.hotplug.poll_init_work); } -- 2.37.2

4 months, 2 weeks

4
5
0 0

[PATCH v1 1/1] mfd: rk8xx: Fix shutdown handler

by Sebastian Reichel

When I converted rk808 to device managed resources I converted the rk808 specific pm_power_off handler to devm_register_sys_off_handler() using SYS_OFF_MODE_POWER_OFF_PREPARE, which is allowed to sleep. I did this because the driver's poweroff function makes use of regmap and the backend of that might sleep. But the PMIC poweroff function will kill off the board power and the kernel does some extra steps after the prepare handler. Thus the prepare handler should not be used for the PMIC's poweroff routine. Instead the normal SYS_OFF_MODE_POWER_OFF phase should be used. The old pm_power_off method is also being called from there, so this would have been a cleaner conversion anyways. But it still makes sense to investigate the sleep handling and check if there are any issues. Apparently the Rockchip and Meson I2C drivers (the only platforms using the PMICs handled by this driver) both have support for atomic transfers and thus may be called from the proper poweroff context. Things are different on the SPI side. That is so far only used by rk806 and that one is only used by Rockchip RK3588. Unfortunately the Rockchip SPI driver does not support atomic transfers. That means using the normal POWER_OFF handler would introduce the following error splash during shutdown on all RK3588 boards currently supported upstream: [ 13.761353] ------------[ cut here ]------------ [ 13.761764] Voluntary context switch within RCU read-side critical section! [ 13.761776] WARNING: CPU: 0 PID: 1 at kernel/rcu/tree_plugin.h:330 rcu_note_context_switch+0x3ac/0x404 [ 13.763219] Modules linked in: [ 13.763498] CPU: 0 UID: 0 PID: 1 Comm: systemd-shutdow Not tainted 6.10.0-12284-g2818a9a19514 #1499 [ 13.764297] Hardware name: Rockchip RK3588 EVB1 V10 Board (DT) [ 13.764812] pstate: 604000c9 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 13.765427] pc : rcu_note_context_switch+0x3ac/0x404 [ 13.765871] lr : rcu_note_context_switch+0x3ac/0x404 [ 13.766314] sp : ffff800084f4b5b0 [ 13.766609] x29: ffff800084f4b5b0 x28: ffff00040139b800 x27: 00007dfb4439ae80 [ 13.767245] x26: ffff00040139bc80 x25: 0000000000000000 x24: ffff800082118470 [ 13.767880] x23: 0000000000000000 x22: ffff000400300000 x21: ffff000400300000 [ 13.768515] x20: ffff800083a9d600 x19: ffff0004fee48600 x18: fffffffffffed448 [ 13.769151] x17: 000000040044ffff x16: 005000f2b5503510 x15: 0000000000000048 [ 13.769787] x14: fffffffffffed490 x13: ffff80008473b3c0 x12: 0000000000000900 [ 13.770421] x11: 0000000000000300 x10: ffff800084797bc0 x9 : ffff80008473b3c0 [ 13.771057] x8 : 00000000ffffefff x7 : ffff8000847933c0 x6 : 0000000000000300 [ 13.771692] x5 : 0000000000000301 x4 : 40000000fffff300 x3 : 0000000000000000 [ 13.772328] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000400300000 [ 13.772964] Call trace: [ 13.773184] rcu_note_context_switch+0x3ac/0x404 [ 13.773598] __schedule+0x94/0xb0c [ 13.773907] schedule+0x34/0x104 [ 13.774198] schedule_timeout+0x84/0xfc [ 13.774544] wait_for_completion_timeout+0x78/0x14c [ 13.774980] spi_transfer_one_message+0x588/0x690 [ 13.775403] __spi_pump_transfer_message+0x19c/0x4ec [ 13.775846] __spi_sync+0x2a8/0x3c4 [ 13.776161] spi_write_then_read+0x120/0x208 [ 13.776543] rk806_spi_bus_read+0x54/0x88 [ 13.776905] _regmap_raw_read+0xec/0x16c [ 13.777257] _regmap_bus_read+0x44/0x7c [ 13.777601] _regmap_read+0x60/0xd8 [ 13.777915] _regmap_update_bits+0xf4/0x13c [ 13.778289] regmap_update_bits_base+0x64/0x98 [ 13.778686] rk808_power_off+0x70/0xfc [ 13.779024] sys_off_notify+0x40/0x6c [ 13.779356] atomic_notifier_call_chain+0x60/0x90 [ 13.779776] do_kernel_power_off+0x54/0x6c [ 13.780146] machine_power_off+0x18/0x24 [ 13.780499] kernel_power_off+0x70/0x7c [ 13.780845] __do_sys_reboot+0x210/0x270 [ 13.781198] __arm64_sys_reboot+0x24/0x30 [ 13.781558] invoke_syscall+0x48/0x10c [ 13.781897] el0_svc_common+0x3c/0xe8 [ 13.782228] do_el0_svc+0x20/0x2c [ 13.782528] el0_svc+0x34/0xd8 [ 13.782806] el0t_64_sync_handler+0x120/0x12c [ 13.783197] el0t_64_sync+0x190/0x194 [ 13.783527] ---[ end trace 0000000000000000 ]--- To avoid this we keep the SYS_OFF_MODE_POWER_OFF_PREPARE handler for the SPI backend. This is not great, but at least avoids regressions and the fix should be small enough to allow backporting. As a side-effect this also works around a shutdown problem on the Asus C201. For reasons unknown that skips calling the prepare handler and directly calls the final shutdown handler. Fixes: 4fec8a5a85c49 ("mfd: rk808: Convert to device managed resources") Cc: stable(a)vger.kernel.org Reported-by: Urja <urja(a)urja.dev> Signed-off-by: Sebastian Reichel <sebastian.reichel(a)collabora.com> --- drivers/mfd/rk8xx-core.c | 15 +++++++++++++-- drivers/mfd/rk8xx-i2c.c | 2 +- drivers/mfd/rk8xx-spi.c | 2 +- include/linux/mfd/rk808.h | 2 +- 4 files changed, 16 insertions(+), 5 deletions(-) diff --git a/drivers/mfd/rk8xx-core.c b/drivers/mfd/rk8xx-core.c index 5eda3c0dbbdf..757ef8181328 100644 --- a/drivers/mfd/rk8xx-core.c +++ b/drivers/mfd/rk8xx-core.c @@ -692,10 +692,11 @@ void rk8xx_shutdown(struct device *dev) } EXPORT_SYMBOL_GPL(rk8xx_shutdown); -int rk8xx_probe(struct device *dev, int variant, unsigned int irq, struct regmap *regmap) +int rk8xx_probe(struct device *dev, int variant, unsigned int irq, struct regmap *regmap, bool is_spi) { struct rk808 *rk808; const struct rk808_reg_data *pre_init_reg; + enum sys_off_mode pwr_off_mode = SYS_OFF_MODE_POWER_OFF; const struct mfd_cell *cells; int dual_support = 0; int nr_pre_init_regs; @@ -785,10 +786,20 @@ int rk8xx_probe(struct device *dev, int variant, unsigned int irq, struct regmap if (ret) return dev_err_probe(dev, ret, "failed to add MFD devices\n"); + /* + * Currently the Rockchip SPI driver always sleeps when doing SPI + * transfers. This is not allowed in the SYS_OFF_MODE_POWER_OFF + * handler, so we are using the prepare handler as a workaround. + * This should be removed once the Rockchip SPI driver has been + * adapted. + */ + if (is_spi) + pwr_off_mode = SYS_OFF_MODE_POWER_OFF_PREPARE; + if (device_property_read_bool(dev, "rockchip,system-power-controller") || device_property_read_bool(dev, "system-power-controller")) { ret = devm_register_sys_off_handler(dev, - SYS_OFF_MODE_POWER_OFF_PREPARE, SYS_OFF_PRIO_HIGH, + pwr_off_mode, SYS_OFF_PRIO_HIGH, &rk808_power_off, rk808); if (ret) return dev_err_probe(dev, ret, diff --git a/drivers/mfd/rk8xx-i2c.c b/drivers/mfd/rk8xx-i2c.c index 69a6b297d723..a2029decd654 100644 --- a/drivers/mfd/rk8xx-i2c.c +++ b/drivers/mfd/rk8xx-i2c.c @@ -189,7 +189,7 @@ static int rk8xx_i2c_probe(struct i2c_client *client) return dev_err_probe(&client->dev, PTR_ERR(regmap), "regmap initialization failed\n"); - return rk8xx_probe(&client->dev, data->variant, client->irq, regmap); + return rk8xx_probe(&client->dev, data->variant, client->irq, regmap, false); } static void rk8xx_i2c_shutdown(struct i2c_client *client) diff --git a/drivers/mfd/rk8xx-spi.c b/drivers/mfd/rk8xx-spi.c index 3405fb82ff9f..20f9428f94bb 100644 --- a/drivers/mfd/rk8xx-spi.c +++ b/drivers/mfd/rk8xx-spi.c @@ -94,7 +94,7 @@ static int rk8xx_spi_probe(struct spi_device *spi) return dev_err_probe(&spi->dev, PTR_ERR(regmap), "Failed to init regmap\n"); - return rk8xx_probe(&spi->dev, RK806_ID, spi->irq, regmap); + return rk8xx_probe(&spi->dev, RK806_ID, spi->irq, regmap, true); } static const struct of_device_id rk8xx_spi_of_match[] = { diff --git a/include/linux/mfd/rk808.h b/include/linux/mfd/rk808.h index 69cbea78b430..be15b84cff9e 100644 --- a/include/linux/mfd/rk808.h +++ b/include/linux/mfd/rk808.h @@ -1349,7 +1349,7 @@ struct rk808 { }; void rk8xx_shutdown(struct device *dev); -int rk8xx_probe(struct device *dev, int variant, unsigned int irq, struct regmap *regmap); +int rk8xx_probe(struct device *dev, int variant, unsigned int irq, struct regmap *regmap, bool is_spi); int rk8xx_suspend(struct device *dev); int rk8xx_resume(struct device *dev); -- 2.43.0

4 months, 3 weeks

8
12
0 0

[PATCH] drm: Remove redundant statement in drm_crtc_helper_set_mode()

by Huacai Chen

Commit dbbfaf5f2641a ("drm: Remove bridge support from legacy helpers") removes the drm_bridge_mode_fixup() call in drm_crtc_helper_set_mode(), which makes the subsequent "encoder_funcs = encoder->helper_private" be redundant, so remove it. Cc: stable(a)vger.kernel.org Fixes: dbbfaf5f2641a ("drm: Remove bridge support from legacy helpers") Signed-off-by: Huacai Chen <chenhuacai(a)loongson.cn> --- drivers/gpu/drm/drm_crtc_helper.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c index 0955f1c385dd..39497493f74c 100644 --- a/drivers/gpu/drm/drm_crtc_helper.c +++ b/drivers/gpu/drm/drm_crtc_helper.c @@ -334,7 +334,6 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc, if (!encoder_funcs) continue; - encoder_funcs = encoder->helper_private; if (encoder_funcs->mode_fixup) { if (!(ret = encoder_funcs->mode_fixup(encoder, mode, adjusted_mode))) { -- 2.43.5

4 months, 3 weeks

3
5
0 0

[PATCH v2] sched/fair: Fix integer underflow

by Pierre Gondois

(struct sg_lb_stats).idle_cpus is of type 'unsigned int'. (local->idle_cpus - busiest->idle_cpus) can underflow to UINT_MAX for instance, and max_t(long, 0, UINT_MAX) will output UINT_MAX. Use lsub_positive() instead of max_t(). Fixes: 16b0a7a1a0af ("sched/fair: Ensure tasks spreading in LLC during LB") cc: stable(a)vger.kernel.org Signed-off-by: Pierre Gondois <pierre.gondois(a)arm.com> Reviewed-by: Vincent Guittot <vincent.guittot(a)linaro.org> --- kernel/sched/fair.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9057584ec06d..6d9124499f52 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -10775,8 +10775,8 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s * idle CPUs. */ env->migration_type = migrate_task; - env->imbalance = max_t(long, 0, - (local->idle_cpus - busiest->idle_cpus)); + env->imbalance = local->idle_cpus; + lsub_positive(&env->imbalance, busiest->idle_cpus); } #ifdef CONFIG_NUMA -- 2.25.1

4 months, 4 weeks

2
2
0 0

[PATCH 6.1.y 6.6.y 0/3] mm/filemap: fix page cache corruption with large folios

by Kairui Song

From: Kairui Song <kasong(a)tencent.com> This series fixes the page cache corruption issue reported by Christian Theune [1]. The issue was reported affects kernels back to 5.19. Current maintained effected branches includes 6.1 and 6.6 and the fix was included in 6.10 already. This series can be applied for both 6.1 and 6.6. Patch 3/3 is the fixing patch. It was initially submitted and merge as an optimization but found to have fixed the corruption by handling race correctly. Patch 1/3 and 2/3 is required for 3/3. Patch 3/3 included some unit test code, making the LOC of the backport a bit higher, but should be OK to be kept, since they are just test code. Note there seems still some unresolved problem in Link [1] but that should be a different issue, and the commits being backported have been well tested, they fix the corruption issue just fine. Link: https://lore.kernel.org/linux-mm/A5A976CB-DB57-4513-A700-656580488AB6@flyin… [1] Kairui Song (3): mm/filemap: return early if failed to allocate memory for split lib/xarray: introduce a new helper xas_get_order mm/filemap: optimize filemap folio adding include/linux/xarray.h | 6 +++ lib/test_xarray.c | 93 ++++++++++++++++++++++++++++++++++++++++++ lib/xarray.c | 49 ++++++++++++++-------- mm/filemap.c | 50 ++++++++++++++++++----- 4 files changed, 169 insertions(+), 29 deletions(-) -- 2.46.1

4 months, 4 weeks

6
14
0 0

[PATCH v5 01/16] x86/stackprotector: Work around strict Clang TLS symbol requirements

by Brian Gerst

From: Ard Biesheuvel <ardb(a)kernel.org> GCC and Clang both implement stack protector support based on Thread Local Storage (TLS) variables, and this is used in the kernel to implement per-task stack cookies, by copying a task's stack cookie into a per-CPU variable every time it is scheduled in. Both now also implement -mstack-protector-guard-symbol=, which permits the TLS variable to be specified directly. This is useful because it will allow us to move away from using a fixed offset of 40 bytes into the per-CPU area on x86_64, which requires a lot of special handling in the per-CPU code and the runtime relocation code. However, while GCC is rather lax in its implementation of this command line option, Clang actually requires that the provided symbol name refers to a TLS variable (i.e., one declared with __thread), although it also permits the variable to be undeclared entirely, in which case it will use an implicit declaration of the right type. The upshot of this is that Clang will emit the correct references to the stack cookie variable in most cases, e.g., 10d: 64 a1 00 00 00 00 mov %fs:0x0,%eax 10f: R_386_32 __stack_chk_guard However, if a non-TLS definition of the symbol in question is visible in the same compilation unit (which amounts to the whole of vmlinux if LTO is enabled), it will drop the per-CPU prefix and emit a load from a bogus address. Work around this by using a symbol name that never occurs in C code, and emit it as an alias in the linker script. Fixes: 3fb0fdb3bbe7 ("x86/stackprotector/32: Make the canary into a regular percpu variable") Cc: <stable(a)vger.kernel.org> Cc: Fangrui Song <i(a)maskray.me> Cc: Uros Bizjak <ubizjak(a)gmail.com> Cc: Nathan Chancellor <nathan(a)kernel.org> Cc: Andy Lutomirski <luto(a)kernel.org> Link: https://github.com/ClangBuiltLinux/linux/issues/1854 Signed-off-by: Ard Biesheuvel <ardb(a)kernel.org> Signed-off-by: Brian Gerst <brgerst(a)gmail.com> --- arch/x86/Makefile | 5 +++-- arch/x86/entry/entry.S | 16 ++++++++++++++++ arch/x86/include/asm/asm-prototypes.h | 3 +++ arch/x86/kernel/cpu/common.c | 2 ++ arch/x86/kernel/vmlinux.lds.S | 3 +++ 5 files changed, 27 insertions(+), 2 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index cd75e78a06c1..5b773b34768d 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -142,9 +142,10 @@ ifeq ($(CONFIG_X86_32),y) ifeq ($(CONFIG_STACKPROTECTOR),y) ifeq ($(CONFIG_SMP),y) - KBUILD_CFLAGS += -mstack-protector-guard-reg=fs -mstack-protector-guard-symbol=__stack_chk_guard + KBUILD_CFLAGS += -mstack-protector-guard-reg=fs \ + -mstack-protector-guard-symbol=__ref_stack_chk_guard else - KBUILD_CFLAGS += -mstack-protector-guard=global + KBUILD_CFLAGS += -mstack-protector-guard=global endif endif else diff --git a/arch/x86/entry/entry.S b/arch/x86/entry/entry.S index 324686bca368..b7ea3e8e9ecc 100644 --- a/arch/x86/entry/entry.S +++ b/arch/x86/entry/entry.S @@ -51,3 +51,19 @@ EXPORT_SYMBOL_GPL(mds_verw_sel); .popsection THUNK warn_thunk_thunk, __warn_thunk + +#ifndef CONFIG_X86_64 +/* + * Clang's implementation of TLS stack cookies requires the variable in + * question to be a TLS variable. If the variable happens to be defined as an + * ordinary variable with external linkage in the same compilation unit (which + * amounts to the whole of vmlinux with LTO enabled), Clang will drop the + * segment register prefix from the references, resulting in broken code. Work + * around this by avoiding the symbol used in -mstack-protector-guard-symbol= + * entirely in the C code, and use an alias emitted by the linker script + * instead. + */ +#ifdef CONFIG_STACKPROTECTOR +EXPORT_SYMBOL(__ref_stack_chk_guard); +#endif +#endif diff --git a/arch/x86/include/asm/asm-prototypes.h b/arch/x86/include/asm/asm-prototypes.h index 25466c4d2134..3674006e3974 100644 --- a/arch/x86/include/asm/asm-prototypes.h +++ b/arch/x86/include/asm/asm-prototypes.h @@ -20,3 +20,6 @@ extern void cmpxchg8b_emu(void); #endif +#if defined(__GENKSYMS__) && defined(CONFIG_STACKPROTECTOR) +extern unsigned long __ref_stack_chk_guard; +#endif diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 8f41ab219cf1..9d42bd15e06c 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2091,8 +2091,10 @@ void syscall_init(void) #ifdef CONFIG_STACKPROTECTOR DEFINE_PER_CPU(unsigned long, __stack_chk_guard); +#ifndef CONFIG_SMP EXPORT_PER_CPU_SYMBOL(__stack_chk_guard); #endif +#endif #endif /* CONFIG_X86_64 */ diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 410546bacc0f..d61c3584f3e6 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -468,6 +468,9 @@ SECTIONS . = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE), "kernel image bigger than KERNEL_IMAGE_SIZE"); +/* needed for Clang - see arch/x86/entry/entry.S */ +PROVIDE(__ref_stack_chk_guard = __stack_chk_guard); + #ifdef CONFIG_X86_64 /* * Per-cpu symbols which need to be offset from __per_cpu_load -- 2.47.0

5 months, 1 week

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Re: [PATCH 1/2] arm64: efi: Execute runtime services from a dedicated stack

by Lee Jones

On Mon, 05 Dec 2022, Ard Biesheuvel wrote: > With the introduction of PRMT in the ACPI subsystem, the EFI rts > workqueue is no longer the only caller of efi_call_virt_pointer() in the > kernel. This means the EFI runtime services lock is no longer sufficient > to manage concurrent calls into firmware, but also that firmware calls > may occur that are not marshalled via the workqueue mechanism, but > originate directly from the caller context. > > For added robustness, and to ensure that the runtime services have 8 KiB > of stack space available as per the EFI spec, introduce a spinlock > protected EFI runtime stack of 8 KiB, where the spinlock also ensures > serialization between the EFI rts workqueue (which itself serializes EFI > runtime calls) and other callers of efi_call_virt_pointer(). > > While at it, use the stack pivot to avoid reloading the shadow call > stack pointer from the ordinary stack, as doing so could produce a > gadget to defeat it. > > Signed-off-by: Ard Biesheuvel <ardb(a)kernel.org> > --- > arch/arm64/include/asm/efi.h | 3 +++ > arch/arm64/kernel/efi-rt-wrapper.S | 13 +++++++++- > arch/arm64/kernel/efi.c | 25 ++++++++++++++++++++ > 3 files changed, 40 insertions(+), 1 deletion(-) Could we have this in Stable please? Upstream commit: ff7a167961d1b ("arm64: efi: Execute runtime services from a dedicated stack") Ard, do we need Patch 2 as well, or can this be applied on its own? > diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h > index 7c12e01c2b312e7b..1c408ec3c8b3a883 100644 > --- a/arch/arm64/include/asm/efi.h > +++ b/arch/arm64/include/asm/efi.h > @@ -25,6 +25,7 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); > ({ \ > efi_virtmap_load(); \ > __efi_fpsimd_begin(); \ > + spin_lock(&efi_rt_lock); \ > }) > > #undef arch_efi_call_virt > @@ -33,10 +34,12 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); > > #define arch_efi_call_virt_teardown() \ > ({ \ > + spin_unlock(&efi_rt_lock); \ > __efi_fpsimd_end(); \ > efi_virtmap_unload(); \ > }) > > +extern spinlock_t efi_rt_lock; > efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...); > > #define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT) > diff --git a/arch/arm64/kernel/efi-rt-wrapper.S b/arch/arm64/kernel/efi-rt-wrapper.S > index 75691a2641c1c0f8..b2786b968fee68dd 100644 > --- a/arch/arm64/kernel/efi-rt-wrapper.S > +++ b/arch/arm64/kernel/efi-rt-wrapper.S > @@ -16,6 +16,12 @@ SYM_FUNC_START(__efi_rt_asm_wrapper) > */ > stp x1, x18, [sp, #16] > > + ldr_l x16, efi_rt_stack_top > + mov sp, x16 > +#ifdef CONFIG_SHADOW_CALL_STACK > + str x18, [sp, #-16]! > +#endif > + > /* > * We are lucky enough that no EFI runtime services take more than > * 5 arguments, so all are passed in registers rather than via the > @@ -29,6 +35,7 @@ SYM_FUNC_START(__efi_rt_asm_wrapper) > mov x4, x6 > blr x8 > > + mov sp, x29 > ldp x1, x2, [sp, #16] > cmp x2, x18 > ldp x29, x30, [sp], #32 > @@ -42,6 +49,10 @@ SYM_FUNC_START(__efi_rt_asm_wrapper) > * called with preemption disabled and a separate shadow stack is used > * for interrupts. > */ > - mov x18, x2 > +#ifdef CONFIG_SHADOW_CALL_STACK > + ldr_l x18, efi_rt_stack_top > + ldr x18, [x18, #-16] > +#endif > + > b efi_handle_corrupted_x18 // tail call > SYM_FUNC_END(__efi_rt_asm_wrapper) > diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c > index a908a37f03678b6b..8cb2e005f8aca589 100644 > --- a/arch/arm64/kernel/efi.c > +++ b/arch/arm64/kernel/efi.c > @@ -144,3 +144,28 @@ asmlinkage efi_status_t efi_handle_corrupted_x18(efi_status_t s, const char *f) > pr_err_ratelimited(FW_BUG "register x18 corrupted by EFI %s\n", f); > return s; > } > + > +DEFINE_SPINLOCK(efi_rt_lock); > + > +asmlinkage u64 *efi_rt_stack_top __ro_after_init; > + > +/* required by the EFI spec */ > +static_assert(THREAD_SIZE >= SZ_8K); > + > +int __init arm64_efi_rt_init(void) > +{ > + void *p = __vmalloc_node_range(THREAD_SIZE, THREAD_ALIGN, > + VMALLOC_START, VMALLOC_END, GFP_KERNEL, > + PAGE_KERNEL, 0, NUMA_NO_NODE, > + __builtin_return_address(0)); > + > + if (!p) { > + pr_warn("Failed to allocate EFI runtime stack\n"); > + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); > + return -ENOMEM; > + } > + > + efi_rt_stack_top = p + THREAD_SIZE; > + return 0; > +} > +core_initcall(arm64_efi_rt_init); > -- > 2.35.1 > > -- Lee Jones [李琼斯]

5 months, 2 weeks

6
13
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[PATCH v6 4/8] crypto: ccp: Fix uapi definitions of PSP errors

by Dionna Glaze

From: Alexey Kardashevskiy <aik(a)amd.com> Additions to the error enum after the explicit 0x27 setting for SEV_RET_INVALID_KEY leads to incorrect value assignments. Use explicit values to match the manufacturer specifications more clearly. Fixes: 3a45dc2b419e ("crypto: ccp: Define the SEV-SNP commands") CC: Sean Christopherson <seanjc(a)google.com> CC: Paolo Bonzini <pbonzini(a)redhat.com> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Ingo Molnar <mingo(a)redhat.com> CC: Borislav Petkov <bp(a)alien8.de> CC: Dave Hansen <dave.hansen(a)linux.intel.com> CC: Ashish Kalra <ashish.kalra(a)amd.com> CC: Tom Lendacky <thomas.lendacky(a)amd.com> CC: John Allen <john.allen(a)amd.com> CC: Herbert Xu <herbert(a)gondor.apana.org.au> CC: "David S. Miller" <davem(a)davemloft.net> CC: Michael Roth <michael.roth(a)amd.com> CC: Luis Chamberlain <mcgrof(a)kernel.org> CC: Russ Weight <russ.weight(a)linux.dev> CC: Danilo Krummrich <dakr(a)redhat.com> CC: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> CC: "Rafael J. Wysocki" <rafael(a)kernel.org> CC: Tianfei zhang <tianfei.zhang(a)intel.com> CC: Alexey Kardashevskiy <aik(a)amd.com> CC: stable(a)vger.kernel.org Signed-off-by: Alexey Kardashevskiy <aik(a)amd.com> Signed-off-by: Dionna Glaze <dionnaglaze(a)google.com> --- include/uapi/linux/psp-sev.h | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/include/uapi/linux/psp-sev.h b/include/uapi/linux/psp-sev.h index 832c15d9155bd..eeb20dfb1fdaa 100644 --- a/include/uapi/linux/psp-sev.h +++ b/include/uapi/linux/psp-sev.h @@ -73,13 +73,20 @@ typedef enum { SEV_RET_INVALID_PARAM, SEV_RET_RESOURCE_LIMIT, SEV_RET_SECURE_DATA_INVALID, - SEV_RET_INVALID_KEY = 0x27, - SEV_RET_INVALID_PAGE_SIZE, - SEV_RET_INVALID_PAGE_STATE, - SEV_RET_INVALID_MDATA_ENTRY, - SEV_RET_INVALID_PAGE_OWNER, - SEV_RET_INVALID_PAGE_AEAD_OFLOW, - SEV_RET_RMP_INIT_REQUIRED, + SEV_RET_INVALID_PAGE_SIZE = 0x0019, + SEV_RET_INVALID_PAGE_STATE = 0x001A, + SEV_RET_INVALID_MDATA_ENTRY = 0x001B, + SEV_RET_INVALID_PAGE_OWNER = 0x001C, + SEV_RET_AEAD_OFLOW = 0x001D, + SEV_RET_EXIT_RING_BUFFER = 0x001F, + SEV_RET_RMP_INIT_REQUIRED = 0x0020, + SEV_RET_BAD_SVN = 0x0021, + SEV_RET_BAD_VERSION = 0x0022, + SEV_RET_SHUTDOWN_REQUIRED = 0x0023, + SEV_RET_UPDATE_FAILED = 0x0024, + SEV_RET_RESTORE_REQUIRED = 0x0025, + SEV_RET_RMP_INITIALIZATION_FAILED = 0x0026, + SEV_RET_INVALID_KEY = 0x0027, SEV_RET_MAX, } sev_ret_code; -- 2.47.0.277.g8800431eea-goog

5 months, 2 weeks

4
6
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[PATCH AUTOSEL 6.10 01/27] wifi: nl80211: disallow setting special AP channel widths

by Sasha Levin

From: Johannes Berg <johannes.berg(a)intel.com> [ Upstream commit 23daf1b4c91db9b26f8425cc7039cf96d22ccbfe ] Setting the AP channel width is meant for use with the normal 20/40/... MHz channel width progression, and switching around in S1G or narrow channels isn't supported. Disallow that. Reported-by: syzbot+bc0f5b92cc7091f45fb6(a)syzkaller.appspotmail.com Link: https://msgid.link/20240515141600.d4a9590bfe32.I19a32d60097e81b527eafe6b092… Signed-off-by: Johannes Berg <johannes.berg(a)intel.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- net/wireless/nl80211.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 72c7bf5585816..81d5bf186180f 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3419,6 +3419,33 @@ static int __nl80211_set_channel(struct cfg80211_registered_device *rdev, if (chandef.chan != cur_chan) return -EBUSY; + /* only allow this for regular channel widths */ + switch (wdev->links[link_id].ap.chandef.width) { + case NL80211_CHAN_WIDTH_20_NOHT: + case NL80211_CHAN_WIDTH_20: + case NL80211_CHAN_WIDTH_40: + case NL80211_CHAN_WIDTH_80: + case NL80211_CHAN_WIDTH_80P80: + case NL80211_CHAN_WIDTH_160: + case NL80211_CHAN_WIDTH_320: + break; + default: + return -EINVAL; + } + + switch (chandef.width) { + case NL80211_CHAN_WIDTH_20_NOHT: + case NL80211_CHAN_WIDTH_20: + case NL80211_CHAN_WIDTH_40: + case NL80211_CHAN_WIDTH_80: + case NL80211_CHAN_WIDTH_80P80: + case NL80211_CHAN_WIDTH_160: + case NL80211_CHAN_WIDTH_320: + break; + default: + return -EINVAL; + } + result = rdev_set_ap_chanwidth(rdev, dev, link_id, &chandef); if (result) -- 2.43.0

6 months

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