PDS Kernel Configuration

addition to a6877bd422

linux-tkg-patches/5.15/0007-v5.15-fsync1_via_futex_waitv.patch

@@ -14,7 +14,7 @@ of Proton to still use fsync in new kernel releases.
 Signed-off-by: André Almeida <andrealmeid@collabora.com>
 ---
  include/uapi/linux/futex.h | 12 ++++++
- kernel/futex.c             | 75 +++++++++++++++++++++++++++++++++++++-
+ kernel/futex/core.c        | 75 +++++++++++++++++++++++++++++++++++++-
  2 files changed, 86 insertions(+), 1 deletion(-)
 
 diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h
@@ -47,10 +47,10 @@ index 2a06b99f9803..417c5d89b745 100644
  
  /*
   * Support for robust futexes: the kernel cleans up held futexes at
-diff --git a/kernel/futex.c b/kernel/futex.c
+diff --git a/kernel/futex/core.c b/kernel/futex/core.c
 index 4a9e7ce3714a..c3f2e65afab8 100644
---- a/kernel/futex.c
+--- a/kernel/futex/core.c
-+++ b/kernel/futex.c
++++ b/kernel/futex/core.c
 @@ -4012,6 +4012,7 @@ static __always_inline bool futex_cmd_has_timeout(u32 cmd)
  	case FUTEX_LOCK_PI2:
  	case FUTEX_WAIT_BITSET:

linux-tkg-patches/5.15/0007-v5.15-futex_waitv.patch

@@ -43,7 +43,7 @@ Link: https://lore.kernel.org/r/20210923171111.300673-17-andrealmeid@collabora.c
  include/linux/syscalls.h          |   6 +
  include/uapi/asm-generic/unistd.h |   5 +-
  include/uapi/linux/futex.h        |  26 +++
- kernel/futex.c                    | 334 ++++++++++++++++++++++++++++++
+ kernel/futex/core.c               | 334 ++++++++++++++++++++++++++++++
  kernel/sys_ni.c                   |   1 +
  5 files changed, 371 insertions(+), 1 deletion(-)
 
@@ -125,10 +125,10 @@ index a89eb0accd5e..1666f5e4b837 100644
  /*
   * Support for robust futexes: the kernel cleans up held futexes at
   * thread exit time.
-diff --git a/kernel/futex.c b/kernel/futex.c
+diff --git a/kernel/futex/core.c b/kernel/futex/core.c
 index 408cad5e8968..d7dc0bd9379c 100644
---- a/kernel/futex.c
+--- a/kernel/futex/core.c
-+++ b/kernel/futex.c
++++ b/kernel/futex/core.c
 @@ -285,6 +285,18 @@ static const struct futex_q futex_q_init = {
  	.requeue_state	= ATOMIC_INIT(Q_REQUEUE_PI_NONE),
  };

linux-tkg-patches/6.1/0012-misc-additions.patch

@@ -314,99 +314,3 @@ index 8c6517d29b8e0c..37068542aafe7f 100644
  		mutex_unlock(&ggtt->vm.mutex);
  	}
 
-From 189603b802a2bb276b82a0a4f66528ad29156f46 Mon Sep 17 00:00:00 2001
-From: Alexey Izbyshev <izbyshev@ispras.ru>
-Date: Sat, 12 Nov 2022 00:54:39 +0300
-Subject: [PATCH] futex: Resend potentially swallowed owner death notification
-
-Commit ca16d5bee598 ("futex: Prevent robust futex exit race") addressed
-two cases when tasks waiting on a robust non-PI futex remained blocked
-despite the futex not being owned anymore:
-
-* if the owner died after writing zero to the futex word, but before
-  waking up a waiter
-
-* if a task waiting on the futex was woken up, but died before updating
-  the futex word (effectively swallowing the notification without acting
-  on it)
-
-In the second case, the task could be woken up either by the previous
-owner (after the futex word was reset to zero) or by the kernel (after
-the OWNER_DIED bit was set and the TID part of the futex word was reset
-to zero) if the previous owner died without the resetting the futex.
-
-Because the referenced commit wakes up a potential waiter only if the
-whole futex word is zero, the latter subcase remains unaddressed.
-
-Fix this by looking only at the TID part of the futex when deciding
-whether a wake up is needed.
-
-Fixes: ca16d5bee598 ("futex: Prevent robust futex exit race")
-Signed-off-by: Alexey Izbyshev <izbyshev@ispras.ru>
-Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
-Link: https://lore.kernel.org/r/20221111215439.248185-1-izbyshev@ispras.ru
----
- kernel/futex/core.c | 26 +++++++++++++++++---------
- 1 file changed, 17 insertions(+), 9 deletions(-)
-
-diff --git a/kernel/futex/core.c b/kernel/futex/core.c
-index b22ef1efe75118..514e4582b86341 100644
---- a/kernel/futex/core.c
-+++ b/kernel/futex/core.c
-@@ -638,6 +638,7 @@ static int handle_futex_death(u32 __user *uaddr, struct task_struct *curr,
- 			      bool pi, bool pending_op)
- {
- 	u32 uval, nval, mval;
-+	pid_t owner;
- 	int err;
-
- 	/* Futex address must be 32bit aligned */
-@@ -659,6 +660,10 @@ static int handle_futex_death(u32 __user *uaddr, struct task_struct *curr,
- 	 * 2. A woken up waiter is killed before it can acquire the
- 	 *    futex in user space.
- 	 *
-+	 * In the second case, the wake up notification could be generated
-+	 * by the unlock path in user space after setting the futex value
-+	 * to zero or by the kernel after setting the OWNER_DIED bit below.
-+	 *
- 	 * In both cases the TID validation below prevents a wakeup of
- 	 * potential waiters which can cause these waiters to block
- 	 * forever.
-@@ -667,24 +672,27 @@ static int handle_futex_death(u32 __user *uaddr, struct task_struct *curr,
- 	 *
- 	 *	1) task->robust_list->list_op_pending != NULL
- 	 *	   @pending_op == true
--	 *	2) User space futex value == 0
-+	 *	2) The owner part of user space futex value == 0
- 	 *	3) Regular futex: @pi == false
- 	 *
- 	 * If these conditions are met, it is safe to attempt waking up a
- 	 * potential waiter without touching the user space futex value and
--	 * trying to set the OWNER_DIED bit. The user space futex value is
--	 * uncontended and the rest of the user space mutex state is
--	 * consistent, so a woken waiter will just take over the
--	 * uncontended futex. Setting the OWNER_DIED bit would create
--	 * inconsistent state and malfunction of the user space owner died
--	 * handling.
-+	 * trying to set the OWNER_DIED bit. If the futex value is zero,
-+	 * the rest of the user space mutex state is consistent, so a woken
-+	 * waiter will just take over the uncontended futex. Setting the
-+	 * OWNER_DIED bit would create inconsistent state and malfunction
-+	 * of the user space owner died handling. Otherwise, the OWNER_DIED
-+	 * bit is already set, and the woken waiter is expected to deal with
-+	 * this.
- 	 */
--	if (pending_op && !pi && !uval) {
-+	owner = uval & FUTEX_TID_MASK;
-+
-+	if (pending_op && !pi && !owner) {
- 		futex_wake(uaddr, 1, 1, FUTEX_BITSET_MATCH_ANY);
- 		return 0;
- 	}
-
--	if ((uval & FUTEX_TID_MASK) != task_pid_vnr(curr))
-+	if (owner != task_pid_vnr(curr))
- 		return 0;
-
- 	/*