kernel_samsung_a53x/drivers/android
Carlos Llamas 21b458825a binder: signal epoll threads of self-work
commit 97830f3c3088638ff90b20dfba2eb4d487bf14d7 upstream.

In (e)poll mode, threads often depend on I/O events to determine when
data is ready for consumption. Within binder, a thread may initiate a
command via BINDER_WRITE_READ without a read buffer and then make use
of epoll_wait() or similar to consume any responses afterwards.

It is then crucial that epoll threads are signaled via wakeup when they
queue their own work. Otherwise, they risk waiting indefinitely for an
event leaving their work unhandled. What is worse, subsequent commands
won't trigger a wakeup either as the thread has pending work.

Fixes: 457b9a6f09f0 ("Staging: android: add binder driver")
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Martijn Coenen <maco@android.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Steven Moreland <smoreland@google.com>
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20240131215347.1808751-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 12:13:30 +01:00
..
binder.c binder: signal epoll threads of self-work 2024-11-18 12:13:30 +01:00
binder_alloc.c binder: fix race between mmput() and do_exit() 2024-11-18 12:12:45 +01:00
binder_alloc.h Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
binder_alloc_selftest.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
binder_internal.h Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
binder_trace.h Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
binderfs.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
debug_symbols.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
Kconfig Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
Makefile Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
vendor_hooks.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00