examples:
There are two threads involved: thread A with a priority of 100 and
thread B with a priority of 101. Here's how they interact:
When thread A releases a semaphore, thread B is scheduled to execute
some code and may reacquire the semaphore. If no other tasks are ready,
thread A will be scheduled to run.
This continuous process can lead to a busy loop.
Thread A: Thread B:
while (nxsem_get_value(&priv->wait, &semcount) >= 0 && <---
semcount <= 0) | 2)context switch
{ 1)contex switch |
nxsem_post(&priv->wait); -------------> run some code and nxsem_wait again
}
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
misc/rpmsgblk_server.c:135:16: warning: format '%d' expects argument of type 'int', but argument 3 has type 'int32_t' {aka 'long int'} [-Wformat=]
135 | ferr("block device open failed, ret=%d\n", msg->header.result);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~
| |
| int32_t {aka long int}
misc/rpmsgblk_server.c:135:48: note: format string is defined here
135 | ferr("block device open failed, ret=%d\n", msg->header.result);
| ~^
| |
| int
| %ld
misc/rpmsgblk_server.c: In function 'rpmsgblk_close_handler':
misc/rpmsgblk_server.c:170:16: warning: format '%d' expects argument of type 'int', but argument 3 has type 'int32_t' {aka 'long int'} [-Wformat=]
170 | ferr("block device close failed, ret=%d\n", msg->header.result);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~
| |
| int32_t {aka long int}
misc/rpmsgblk_server.c:170:49: note: format string is defined here
170 | ferr("block device close failed, ret=%d\n", msg->header.result);
| ~^
| |
| int
| %ld
Signed-off-by: Bowen Wang <wangbowen6@xiaomi.com>
This forces the bch layer to read the sector from the physical device
instead of using the cached values. It is necessary to call when the
device is updated from the different source than bch, for example
erased by the MTD ioctl command.
It also has to invalidate readahead buffer from FTL if option
CONFIG_DRVR_READAHEAD is set.
Signed-off-by: Michal Lenc <michallenc@seznam.cz>
* Make readv/writev implementations update struct uio
This can simplify partial result handling.
* change the error number on the overflow from EOVERFLOW to EINVAL
to match NetBSD
* add a commented out uio_offset field. I used "#if 0" here as
C comments can't nest.
* add a few helper functions
Note on uio_copyfrom/uio_copyto:
although i'm not quite happy with the "offset" functionality,
it's necessary to simplify the adaptation of some drivers like
drivers/serial/serial.c, which (ab)uses the user-supplied buffer
as a line-buffer.
/dev/zero is a very commonly used config, for example use
/dev/zero to test the filesystem, mtd or block devices performance.
So let's default enable it when not enable DEFAULT_SMALL
Signed-off-by: Bowen Wang <wangbowen6@xiaomi.com>
when client read and poll wait buffer from server side and server side may
poll notify more than one times, then rpmsgdev in client side will call
"rpmsgdev_poll_setup(priv, 0, false);" twice which will cause crash in
vela rpmsgdev_server.c
Signed-off-by: rongyichang <rongyichang@xiaomi.com>
the msg count is not changed while iov len is increased.
which may cause the buffer reply by server is bigger than
msg count
Signed-off-by: rongyichang <rongyichang@xiaomi.com>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
This patch fixed userspace headers conflict. Architecture-related definition and API should not be exposed to users.
Signed-off-by: ouyangxiangzhen <ouyangxiangzhen@xiaomi.com>
currently, nuttx implements readv/writev on the top of read/write.
while it might work for the simplest cases, it's broken by design.
for example, it's impossible to make it work correctly for files
which need to preserve data boundaries without allocating a single
contiguous buffer. (udp socket, some character devices, etc)
this change is a start of the migration to a better design.
that is, implement read/write on the top of readv/writev.
to avoid a single huge change, following things will NOT be done in
this commit:
* fix actual bugs caused by the original readv-based-on-read design.
(cf. https://github.com/apache/nuttx/pull/12674)
* adapt filesystems/drivers to actually benefit from the new interface.
(except a few trivial examples)
* eventually retire the old interface.
* retire read/write syscalls. implement them in libc instead.
* pread/pwrite/preadv/pwritev (except the introduction of struct uio,
which is a preparation to back these variations with the new
interface.)
A use-after-free problem occurs when there are multiple remotes in the list `g_rpmsg` and the matching remote is not the last item in the list.
Log
# Export the device "/dev/LOCAL_DEV" to remote "REMOTE_CPU"
ap> testdev -d 2 -c "REMOTE_CPU" -l "/dev/LOCAL_DEV"
[ap] kasan_report: kasan detected a read access error, address at 0x3c3d4740,size is 4, return address: 0x2c33620f
[ap] kasan_show_memory: Shadow bytes around the buggy address:
[ap] kasan_show_memory: 0x3c3d46f0: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4700: aa aa aa aa cc cc cc cc cc cc cc cc cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4710: 40 47 3d 3c ed 61 33 2c 00 00 00 00 00 00 00 00
[ap] kasan_show_memory: 0x3c3d4720: 00 00 00 00 00 00 00 00 00 00 00 00 cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4730: 55 55 55 55 38 00 00 00 02 2c 00 00 cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4740:[00 00 00 00]66 e0 42 3c cc cc cc cc cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4750: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4760: aa aa aa aa 38 00 00 00 01 2c 00 00 cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4770: 50 57 44 3d 2f 00 cc cc cc cc cc cc cc cc cc cc
[ap] kasan_show_memory: 0x3c3d4780: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
[ap] dump_assert_info: Current Version: NuttX ****** ***** *** 12.3.0 **********-***** *** ** 2024 **:**:** arm
[ap] dump_assert_info: Assertion failed panic: at file: kasan/hook.c:187 task: testdev process: testdev 0x2ca20495
$ addr2line -fe nuttx/nuttx 0x2c33620f
rpmsgdev_server_created
/workspace/nuttx/drivers/misc/rpmsgdev_server.c:529
# Line 529 => strcmp()
Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
Rpmsg dev server always open the real char device with nonblock mode,
so let client try to read/wrtie the read device every read/write
operation.
Signed-off-by: Bowen Wang <wangbowen6@xiaomi.com>
misc/rpmsgblk.c:616:29: warning: implicit declaration of function ‘rpmsg_virtio_get_buffer_size’; did you mean ‘rpmsg_get_rx_buffer_size’? [-Wimplicit-function-declaration]
616 | if (MAX(msglen, rsplen) > rpmsg_virtio_get_buffer_size(priv->ept.rdev))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
| rpmsg_get_rx_buffer_size
Signed-off-by: Yongrong Wang <wangyongrong@xiaomi.com>
x86_64 uses 4-5G virtual addresses, we need to convert them into physical addresses and pass them to qemu, otherwise qemu will fail to map
Signed-off-by: liwenxiang1 <liwenxiang1@xiaomi.com>
when multiple processes call poll and a event occured,
all the processes are waked up. it should wake up one
process based on pipe->id
Signed-off-by: zhanghu5 <zhanghu5@xiaomi.com>
