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, 149 insertions, 0 deletions

diff --git a/include/uapi/asm-generic/termbits.h b/include/uapi/asm-generic/termbits.h
new file mode 100644
index 000000000..890ef2905
--- /dev/null
+++ b/include/uapi/asm-generic/termbits.h
@@ -0,0 +1,149 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef __ASM_GENERIC_TERMBITS_H
+#define __ASM_GENERIC_TERMBITS_H
+
+#include <asm-generic/termbits-common.h>
+
+typedef unsigned int	tcflag_t;
+
+#define NCCS 19
+struct termios {
+	tcflag_t c_iflag;		/* input mode flags */
+	tcflag_t c_oflag;		/* output mode flags */
+	tcflag_t c_cflag;		/* control mode flags */
+	tcflag_t c_lflag;		/* local mode flags */
+	cc_t c_line;			/* line discipline */
+	cc_t c_cc[NCCS];		/* control characters */
+};
+
+struct termios2 {
+	tcflag_t c_iflag;		/* input mode flags */
+	tcflag_t c_oflag;		/* output mode flags */
+	tcflag_t c_cflag;		/* control mode flags */
+	tcflag_t c_lflag;		/* local mode flags */
+	cc_t c_line;			/* line discipline */
+	cc_t c_cc[NCCS];		/* control characters */
+	speed_t c_ispeed;		/* input speed */
+	speed_t c_ospeed;		/* output speed */
+};
+
+struct ktermios {
+	tcflag_t c_iflag;		/* input mode flags */
+	tcflag_t c_oflag;		/* output mode flags */
+	tcflag_t c_cflag;		/* control mode flags */
+	tcflag_t c_lflag;		/* local mode flags */
+	cc_t c_line;			/* line discipline */
+	cc_t c_cc[NCCS];		/* control characters */
+	speed_t c_ispeed;		/* input speed */
+	speed_t c_ospeed;		/* output speed */
+};
+
+/* c_cc characters */
+#define VINTR		 0
+#define VQUIT		 1
+#define VERASE		 2
+#define VKILL		 3
+#define VEOF		 4
+#define VTIME		 5
+#define VMIN		 6
+#define VSWTC		 7
+#define VSTART		 8
+#define VSTOP		 9
+#define VSUSP		10
+#define VEOL		11
+#define VREPRINT	12
+#define VDISCARD	13
+#define VWERASE		14
+#define VLNEXT		15
+#define VEOL2		16
+
+/* c_iflag bits */
+#define IUCLC	0x0200
+#define IXON	0x0400
+#define IXOFF	0x1000
+#define IMAXBEL	0x2000
+#define IUTF8	0x4000
+
+/* c_oflag bits */
+#define OLCUC	0x00002
+#define ONLCR	0x00004
+#define NLDLY	0x00100
+#define   NL0	0x00000
+#define   NL1	0x00100
+#define CRDLY	0x00600
+#define   CR0	0x00000
+#define   CR1	0x00200
+#define   CR2	0x00400
+#define   CR3	0x00600
+#define TABDLY	0x01800
+#define   TAB0	0x00000
+#define   TAB1	0x00800
+#define   TAB2	0x01000
+#define   TAB3	0x01800
+#define   XTABS	0x01800
+#define BSDLY	0x02000
+#define   BS0	0x00000
+#define   BS1	0x02000
+#define VTDLY	0x04000
+#define   VT0	0x00000
+#define   VT1	0x04000
+#define FFDLY	0x08000
+#define   FF0	0x00000
+#define   FF1	0x08000
+
+/* c_cflag bit meaning */
+#define CBAUD		0x0000100f
+#define CSIZE		0x00000030
+#define   CS5		0x00000000
+#define   CS6		0x00000010
+#define   CS7		0x00000020
+#define   CS8		0x00000030
+#define CSTOPB		0x00000040
+#define CREAD		0x00000080
+#define PARENB		0x00000100
+#define PARODD		0x00000200
+#define HUPCL		0x00000400
+#define CLOCAL		0x00000800
+#define CBAUDEX		0x00001000
+#define BOTHER		0x00001000
+#define     B57600	0x00001001
+#define    B115200	0x00001002
+#define    B230400	0x00001003
+#define    B460800	0x00001004
+#define    B500000	0x00001005
+#define    B576000	0x00001006
+#define    B921600	0x00001007
+#define   B1000000	0x00001008
+#define   B1152000	0x00001009
+#define   B1500000	0x0000100a
+#define   B2000000	0x0000100b
+#define   B2500000	0x0000100c
+#define   B3000000	0x0000100d
+#define   B3500000	0x0000100e
+#define   B4000000	0x0000100f
+#define CIBAUD		0x100f0000	/* input baud rate */
+
+/* c_lflag bits */
+#define ISIG	0x00001
+#define ICANON	0x00002
+#define XCASE	0x00004
+#define ECHO	0x00008
+#define ECHOE	0x00010
+#define ECHOK	0x00020
+#define ECHONL	0x00040
+#define NOFLSH	0x00080
+#define TOSTOP	0x00100
+#define ECHOCTL	0x00200
+#define ECHOPRT	0x00400
+#define ECHOKE	0x00800
+#define FLUSHO	0x01000
+#define PENDIN	0x04000
+#define IEXTEN	0x08000
+#define EXTPROC	0x10000
+
+/* tcsetattr uses these */
+#define	TCSANOW		0
+#define	TCSADRAIN	1
+#define	TCSAFLUSH	2
+
+#endif /* __ASM_GENERIC_TERMBITS_H */