Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEADgrafted

Changes:

Make expedited grace periods expedite normal RCU callbacks

Miscellaneous fixes:
 * Improve diagnostic output with character task states.
 * Mark accesses to inform KCSAN of concurrency design.
 * Move from kmalloc() to kmalloc_obj().
 * Documentation updates.
 * Improve handling of RCU deferred quiescent states.
 * Clean up unused function arguments and structure fields.
 * Reduce show_rcu_gp_kthreads() stack space.

Tasks RCU updates:
 * Clean up after SRCU re-implementation of Tasks Trace RCU.
 * Mark accesses to inform KCSAN of concurrency design.
 * Add ->lazy_timer status to diagnostic output.
 * Remove an unnecessary memory barrier.
 * Fix a data race, courtesy of KCSAN.
 * Documentation updates.
 * Convert cond_resched_tasks_rcu_qs() from macro to static inline
   function.

SRCU updates:
 * Add Rust helpers for SRCU.
 * Avoid losing queued work at cleanup_srcu_struct() time.

Torture-test updates:
 * Preparation work for immediate RCU priority deboosting.
 * Test RCU readers from real interrupt handlers (as opposed to softirq).
 * Simplify code through use of cpumask_next_wrap().
 * Improve diagnostic output with character task states.
 * Add rcutorture.nwriters parameter to allow lightweight stall testing,
   and rcutorture.stall_only to make doing so easier.
 * Test an RCU Tasks Trace grace period implying an RCU grace period.
 * Make RCU Tasks Trace torturing track reader batches.
 * Fix a data race, courtesy of KCSAN.
 * Plug a shuffle_tmp_mask memory leak on kthread spawn failure.

1 files changed, 79 insertions, 0 deletions

diff --git a/include/sound/hda_chmap.h b/include/sound/hda_chmap.h
new file mode 100644
index 000000000..e508f3192
--- /dev/null
+++ b/include/sound/hda_chmap.h
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * For multichannel support
+ */
+
+#ifndef __SOUND_HDA_CHMAP_H
+#define __SOUND_HDA_CHMAP_H
+
+#include <sound/pcm.h>
+#include <sound/hdaudio.h>
+
+
+#define SND_PRINT_CHANNEL_ALLOCATION_ADVISED_BUFSIZE 80
+
+struct hdac_cea_channel_speaker_allocation {
+	int ca_index;
+	int speakers[8];
+
+	/* derived values, just for convenience */
+	int channels;
+	int spk_mask;
+};
+struct hdac_chmap;
+
+struct hdac_chmap_ops {
+	/*
+	 * Helpers for producing the channel map TLVs. These can be overridden
+	 * for devices that have non-standard mapping requirements.
+	 */
+	int (*chmap_cea_alloc_validate_get_type)(struct hdac_chmap *chmap,
+		struct hdac_cea_channel_speaker_allocation *cap, int channels);
+	void (*cea_alloc_to_tlv_chmap)(struct hdac_chmap *hchmap,
+		struct hdac_cea_channel_speaker_allocation *cap,
+		unsigned int *chmap, int channels);
+
+	/* check that the user-given chmap is supported */
+	int (*chmap_validate)(struct hdac_chmap *hchmap, int ca,
+			int channels, unsigned char *chmap);
+
+	int (*get_spk_alloc)(struct hdac_device *hdac, int pcm_idx);
+
+	void (*get_chmap)(struct hdac_device *hdac, int pcm_idx,
+					unsigned char *chmap);
+	void (*set_chmap)(struct hdac_device *hdac, int pcm_idx,
+			unsigned char *chmap, int prepared);
+	bool (*is_pcm_attached)(struct hdac_device *hdac, int pcm_idx);
+
+	/* get and set channel assigned to each HDMI ASP (audio sample packet) slot */
+	int (*pin_get_slot_channel)(struct hdac_device *codec,
+			hda_nid_t pin_nid, int asp_slot);
+	int (*pin_set_slot_channel)(struct hdac_device *codec,
+			hda_nid_t pin_nid, int asp_slot, int channel);
+	void (*set_channel_count)(struct hdac_device *codec,
+				hda_nid_t cvt_nid, int chs);
+};
+
+struct hdac_chmap {
+	unsigned int channels_max; /* max over all cvts */
+	struct hdac_chmap_ops ops;
+	struct hdac_device *hdac;
+};
+
+void snd_hdac_register_chmap_ops(struct hdac_device *hdac,
+				struct hdac_chmap *chmap);
+int snd_hdac_channel_allocation(struct hdac_device *hdac, int spk_alloc,
+			int channels, bool chmap_set,
+			bool non_pcm, unsigned char *map);
+int snd_hdac_get_active_channels(int ca);
+void snd_hdac_setup_channel_mapping(struct hdac_chmap *chmap,
+		       hda_nid_t pin_nid, bool non_pcm, int ca,
+		       int channels, unsigned char *map,
+		       bool chmap_set);
+void snd_hdac_print_channel_allocation(int spk_alloc, char *buf, int buflen);
+struct hdac_cea_channel_speaker_allocation *snd_hdac_get_ch_alloc_from_ca(int ca);
+int snd_hdac_chmap_to_spk_mask(unsigned char c);
+int snd_hdac_spk_to_chmap(int spk);
+int snd_hdac_add_chmap_ctls(struct snd_pcm *pcm, int pcm_idx,
+				struct hdac_chmap *chmap);
+#endif /* __SOUND_HDA_CHMAP_H */