diff options
| author | Finn Thain <fthain@telegraphics.com.au> | 2020-05-31 09:12:13 +1000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-19 08:15:56 +0200 |
| commit | b8ad79dde63ffa94810ed6436d0847b6b730797c (patch) | |
| tree | 456f09383fa4cbd507e9e921e683f38829f7404c /arch/m68k | |
| parent | 38702b9081c997256fceb7fb9fab1abfbcc4fde0 (diff) | |
m68k: mac: Don't send IOP message until channel is idle
[ Upstream commit aeb445bf2194d83e12e85bf5c65baaf1f093bd8f ]
In the following sequence of calls, iop_do_send() gets called when the
"send" channel is not in the IOP_MSG_IDLE state:
iop_ism_irq()
iop_handle_send()
(msg->handler)()
iop_send_message()
iop_do_send()
Avoid this by testing the channel state before calling iop_do_send().
When sending, and iop_send_queue is empty, call iop_do_send() because
the channel is idle. If iop_send_queue is not empty, iop_do_send() will
get called later by iop_handle_send().
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Cc: Joshua Thompson <funaho@jurai.org>
Link: https://lore.kernel.org/r/6d667c39e53865661fa5a48f16829d18ed8abe54.1590880333.git.fthain@telegraphics.com.au
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/m68k')
| -rw-r--r-- | arch/m68k/mac/iop.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/arch/m68k/mac/iop.c b/arch/m68k/mac/iop.c index 9bfa17015768..d8f2282978f9 100644 --- a/arch/m68k/mac/iop.c +++ b/arch/m68k/mac/iop.c @@ -416,7 +416,8 @@ static void iop_handle_send(uint iop_num, uint chan) msg->status = IOP_MSGSTATUS_UNUSED; msg = msg->next; iop_send_queue[iop_num][chan] = msg; - if (msg) iop_do_send(msg); + if (msg && iop_readb(iop, IOP_ADDR_SEND_STATE + chan) == IOP_MSG_IDLE) + iop_do_send(msg); } /* @@ -490,16 +491,12 @@ int iop_send_message(uint iop_num, uint chan, void *privdata, if (!(q = iop_send_queue[iop_num][chan])) { iop_send_queue[iop_num][chan] = msg; + iop_do_send(msg); } else { while (q->next) q = q->next; q->next = msg; } - if (iop_readb(iop_base[iop_num], - IOP_ADDR_SEND_STATE + chan) == IOP_MSG_IDLE) { - iop_do_send(msg); - } - return 0; } |