[alsa-devel] commit bd5389278c96f585afcac4058420e4f3ac201d2a introduce big problem

[Scott Jiang]

> I found this bug was introduced by this commit I mentioned.
> From aplay info above, it seems if there is no plugin prior to
> mmap-emul, alsa lib will never send start cmd to driver.
>
Add some strace info,
For S32_LE:
ioctl(4, SNDRV_PCM_IOCTL_HW_REFINE, 0x2cbd854) = 0
ioctl(4, SNDRV_PCM_IOCTL_HW_PARAMS, 0x2cbd854) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4b718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SW_PARAMS, 0x2cbd044) = 0
ioctl(4, SNDRV_PCM_IOCTL_SW_PARAMS, 0x2cbd39c) = 0
ioctl(4, SNDRV_PCM_IOCTL_SW_PARAMS, 0x2cbd718) = 0
ioctl(4, SNDRV_PCM_IOCTL_PREPARE, 0xfffff000) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4b718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4b718) = 0
mmap2(NULL, 12288, PROT_READ|PROT_WRITE,
MAP_SHARED|MAP_ANONYMOUS|0x4000000, 0, 0) = 0x2e54000
ioctl(0, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or
TCGETS, {B57600 opost isig icanon echo ...}) = 0
fcntl(0, F_GETFL)                       = 0x2 (flags O_RDWR)
fcntl(0, F_SETFL, O_RDWR|O_NONBLOCK)    = 0
ioctl(0, SNDCTL_TMR_START or SNDRV_TIMER_IOCTL_TREAD or TCSETS,
{B57600 opost isig -icanon echo ...}) = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or
TCGETS, {B57600 opost isig -icanon echo ...}) = 0
rmdir("1.wav")                          = -1 ENOENT (No such file or directory)
open("1.wav", O_WRONLY|O_CREAT|O_LARGEFILE, 0644) = 3
write(3, "RIFF$\224\21\0WAVE", 12)      = 12
write(3, "fmt \20\0\0\0", 8)            = 8
write(3, "\1\0\2\0\200\273\0\0\0\334\5\0\10\0 \0", 16) = 16
write(3, "data\0\224\21\0", 8)          = 8
read(0, 0x2cbdb2f, 1)                   = -1 EAGAIN (Resource
temporarily unavailable)
ioctl(4, SNDRV_PCM_IOCTL_READI_FRAMES, 0x2cbdb2c) = -1 EIO (Input/output error)
write(2, "arecord", 7arecord)                  = 7
write(2, ": ", 2: )                       = 2
write(2, "pcm_read", 8pcm_read)                 = 8
write(2, ":", 1:)                        = 1
write(2, "1773", 41773)                     = 4
write(2, ": ", 2: )                       = 2
write(2, "read error: ", 12read error: )            = 12
write(2, "Input/output error", 18Input/output error)      = 18
write(2, "\n", 1

And for S16_LE:
ioctl(4, SNDRV_PCM_IOCTL_HW_REFINE, 0x2cbd0d4) = 0
ioctl(4, SNDRV_PCM_IOCTL_HW_PARAMS, 0x2cbd0d4) = -1 EINVAL (Invalid argument)
ioctl(4, SNDRV_PCM_IOCTL_HW_REFINE, 0x2cbd0d4) = 0
ioctl(4, SNDRV_PCM_IOCTL_HW_PARAMS, 0x2cbd0d4) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SW_PARAMS, 0x2cbccdc) = 0
ioctl(4, SNDRV_PCM_IOCTL_SW_PARAMS, 0x2cbd034) = 0
mmap2(NULL, 36864, PROT_READ|PROT_WRITE,
MAP_SHARED|MAP_ANONYMOUS|0x4000000, 0, 0) = 0x2e60000
ioctl(4, SNDRV_PCM_IOCTL_SW_PARAMS, 0x2cbd39c) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_PREPARE, 0xfffff000) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
mmap2(NULL, 8192, PROT_READ|PROT_WRITE,
MAP_SHARED|MAP_ANONYMOUS|0x4000000, 0, 0) = 0x2e54000
ioctl(0, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or
TCGETS, {B57600 opost isig icanon echo ...}) = 0
fcntl(0, F_GETFL)                       = 0x2 (flags O_RDWR)
fcntl(0, F_SETFL, O_RDWR|O_NONBLOCK)    = 0
ioctl(0, SNDCTL_TMR_START or SNDRV_TIMER_IOCTL_TREAD or TCSETS,
{B57600 opost isig -icanon echo ...}) = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or
TCGETS, {B57600 opost isig -icanon echo ...}) = 0
rmdir("1.wav")                          = -1 ENOENT (No such file or directory)
open("1.wav", O_WRONLY|O_CREAT|O_LARGEFILE, 0644) = 3
write(3, "RIFF$\312\10\0WAVE", 12)      = 12
write(3, "fmt \20\0\0\0", 8)            = 8
write(3, "\1\0\2\0\200\273\0\0\0\356\2\0\4\0\20\0", 16) = 16
write(3, "data\0\312\10\0", 8)          = 8
read(0, 0x2cbdb2f, 1)                   = -1 EAGAIN (Resource
temporarily unavailable)
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_START, 0xfffff000) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ppoll([{fd=4, events=POLLIN|POLLERR|POLLNVAL}], 1, NULL, NULL, 8) = 1
([{fd=4, revents=POLLIN}])
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_READI_FRAMES, 0x2cbd9d4) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
write(3, "\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0\352\0"...,
4096) = 4096
read(0, 0x2cbdb2f, 1)                   = -1 EAGAIN (Resource
temporarily unavailable)
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_READI_FRAMES, 0x2cbd9d4) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_SYNC_PTR, 0x2e4c718) = 0
ioctl(4, SNDRV_PCM_IOCTL_READI_FRAMES, 0x2cbd9d4) = 0

So we can see ioctl(4, SNDRV_PCM_IOCTL_START, 0xfffff000) was missed
before ioctl(4, SNDRV_PCM_IOCTL_READI_FRAMES, 0x2cbd9d4) in S32_LE
format test case.

Regards,
Scott