ahci: sata hotplug doesn't work after suspend

[Jiri Slaby <jslaby@suse.cz>]

Hi,

ahci hotplug stopped working here. It always worked (-next-20111206 is
the last known working for sure). I'm using -next and after plugging a
sata disk in, nothing happens. I don't *think* (in the traffic, it's
hard to tell for sure) an interrupt is generated either. I also *think*
that it works before suspend/resume, but not after. (Or maybe uptime
matters?)

This happens before suspend on plug-in:
ata3: exception Emask 0x50 SAct 0x0 SErr 0x40d0800 action 0xe frozen
ata3: irq_stat 0x00000040, connection status changed
ata3: SError: { HostInt PHYRdyChg CommWake 10B8B DevExch }
ata3: hard resetting link
ata3: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata3.00: ATA-8: ST31000528AS, CC38, max UDMA/133
ata3.00: 1953525168 sectors, multi 0: LBA48 NCQ (depth 31/32)
ata3.00: configured for UDMA/133
ata3: EH complete
scsi 2:0:0:0: Direct-Access     ATA      ST31000528AS     CC38 PQ: 0 ANSI: 5
sd 2:0:0:0: [sdc] 1953525168 512-byte logical blocks: (1.00 TB/931 GiB)
sd 2:0:0:0: [sdc] Write Protect is off
sd 2:0:0:0: [sdc] Mode Sense: 00 3a 00 00
sd 2:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't
support DPO or FUA
 sdc: sdc1 sdc2
sd 2:0:0:0: [sdc] Attached SCSI disk

After suspend/resume and plug-in, nothing appears in dmesg. Storing "- -
-" to /sys/class/scsi_host/host*/scan doesn't help. It looks like the
line is completely dead, because only ata1 and ata2 say "hard resetting
link" after this (and another two disks are connected there).

I tried 'echo adapter >host_reset', but I get 'write error: Invalid
argument'.

00:1f.2 SATA controller [0106]: Intel Corporation 82801IR/IO/IH
(ICH9R/DO/DH) 6 port SATA Controller [AHCI mode] [8086:2922] (rev 02)
(prog-if 01 [AHCI 1.0])
        Subsystem: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 6 port
SATA Controller [AHCI mode] [8086:2922]
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
ParErr- Stepping- SERR- FastB2B- DisINTx+
        Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
<TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0
        Interrupt: pin B routed to IRQ 43
        Region 0: I/O ports at cc00 [size=8]
        Region 1: I/O ports at c880 [size=4]
        Region 2: I/O ports at c800 [size=8]
        Region 3: I/O ports at c480 [size=4]
        Region 4: I/O ports at c400 [size=32]
        Region 5: Memory at feb7c800 (32-bit, non-prefetchable) [size=2K]
        Capabilities: [80] MSI: Enable+ Count=1/16 Maskable- 64bit-
                Address: fee0100c  Data: 4171
        Capabilities: [70] Power Management version 3
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
PME(D0-,D1-,D2-,D3hot+,D3cold-)
                Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
        Capabilities: [a8] SATA HBA v1.0 BAR4 Offset=00000004
        Capabilities: [b0] Vendor Specific Information: Len=06 <?>
        Kernel driver in use: ahci

Any ideas what that could be?

thanks,
-- 
js
suse labs