I'm wondering about the following messages, which appeared when I upgraded from
2.4 to 2.6:
| sda: asking for cache data failed
| sda: assuming drive cache: write through
(a larger log snippet below)
I have found another message:
http://groups.google.com/group/fa.linux.kernel/browse_thread/thread/853b2b5a5cc2f837/87bcabcf8a07f065
whosese author asks about whether this means that data inconsistencies can
appear. I also have a megaraid card, and a similar situation, but I have a
bit more general question.
I'm wondering WHY can't the caching mode cannot be obtained by the kernel?
- Is it because the kernel is trying to inquire about the cache on a physical
disk, and the sda and sdb it sees are actually logical drives, and the
situation is perfectly normal?
- Or is it something wrong with the card?
- Or maybe there is no support for such operation in the megaraid
driver?
- Is it something else even? Do I need to do something more to find
out?
The message is simply a little worrying for me, because I don't understand why
the "asking" fails.
here's some context:
| megaraid cmm: 2.20.2.5 (Release Date: Fri Jan 21 00:01:03 EST 2005)
| SCSI subsystem initialized
| megaraid: 2.20.4.5 (Release Date: Thu Feb 03 12:27:22 EST 2005)
| megaraid: probe new device 0x1000:0x0407:0x8086:0x0532: bus 5:slot 0:func 0
| ACPI: PCI Interrupt 0000:05:00.0[A] -> GSI 52 (level, low) -> IRQ 169
| megaraid: fw version:[411M] bios version:[H404]
| scsi0 : LSI Logic MegaRAID driver
| scsi[0]: scanning scsi channel 0 [Phy 0] for non-raid devices
| scsi[0]: scanning scsi channel 1 [Phy 1] for non-raid devices
| scsi[0]: scanning scsi channel 2 [virtual] for logical drives
| Vendor: MegaRAID Model: LD 0 RAID1 35G Rev: 411M
| Type: Direct-Access ANSI SCSI revision: 02
| Vendor: MegaRAID Model: LD 1 RAID5 245G Rev: 411M
| Type: Direct-Access ANSI SCSI revision: 02
[...]
| SCSI device sda: 71772160 512-byte hdwr sectors (36747 MB)
| sda: asking for cache data failed
| sda: assuming drive cache: write through
| SCSI device sda: 71772160 512-byte hdwr sectors (36747 MB)
| sda: asking for cache data failed
| sda: assuming drive cache: write through
| /dev/scsi/host0/bus2/target0/lun0: p1 p2 p3 p4 < p5 p6 p7 >
| Attached scsi disk sda at scsi0, channel 2, id 0, lun 0
| SCSI device sdb: 502720512 512-byte hdwr sectors (257393 MB)
| sdb: asking for cache data failed
| sdb: assuming drive cache: write through
| SCSI device sdb: 502720512 512-byte hdwr sectors (257393 MB)
| sdb: asking for cache data failed
| sdb: assuming drive cache: write through
| /dev/scsi/host0/bus2/target1/lun0: p1 p2
| Attached scsi disk sdb at scsi0, channel 2, id 1, lun 0
This is kernel 2.6.12 with Debian patches.
regards,
Marcin
--
Marcin Owsiany <[email protected]> http://marcin.owsiany.pl/
GnuPG: 1024D/60F41216 FE67 DA2D 0ACA FC5E 3F75 D6F6 3A0D 8AA0 60F4 1216
"Every program in development at MIT expands until it can read mail."
-- Unknown
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
