Re: stopped array, but /sys/block/mdN still exists.

2008-01-03 Thread Neil Brown
On Thursday January 3, [EMAIL PROTECTED] wrote: So what happens if I try to _use_ that /sys entry? For instance run a script which reads data, or sets the stripe_cache_size higher, or whatever? Do I get back status, ignored, or system issues? Try it:-) The stripe_cache_size attributes

Re: PROBLEM: RAID5 reshape data corruption

2008-01-03 Thread Neil Brown
On Monday December 31, [EMAIL PROTECTED] wrote: Ok, since my previous thread didn't seem to attract much attention, let me try again. Thank you for your report and your patience. An interrupted RAID5 reshape will cause the md device in question to contain one corrupt chunk per stripe if

[PATCH] md: Fix data corruption when a degraded raid5 array is reshaped.

2008-01-03 Thread NeilBrown
This patch fixes a fairly serious bug in md/raid5 in 2.6.23 and 24-rc. It would be great if it cold get into 23.13 and 24.final. Thanks. NeilBrown ### Comments for Changeset We currently do not wait for the block from the missing device to be computed from parity before copying data to the new

Re: [PATCH] md: Fix data corruption when a degraded raid5 array is reshaped.

2008-01-03 Thread Dan Williams
On Thu, 2008-01-03 at 15:46 -0700, NeilBrown wrote: This patch fixes a fairly serious bug in md/raid5 in 2.6.23 and 24-rc. It would be great if it cold get into 23.13 and 24.final. Thanks. NeilBrown ### Comments for Changeset We currently do not wait for the block from the missing device

Re: [PATCH] md: Fix data corruption when a degraded raid5 array is reshaped.

2008-01-03 Thread Dan Williams
On Thu, 2008-01-03 at 16:00 -0700, Williams, Dan J wrote: On Thu, 2008-01-03 at 15:46 -0700, NeilBrown wrote: This patch fixes a fairly serious bug in md/raid5 in 2.6.23 and 24-rc. It would be great if it cold get into 23.13 and 24.final. Thanks. NeilBrown ### Comments for Changeset

md raid1 in active-active arrangement

2008-01-03 Thread Clayton Bell
Is it reasonable for a raid1 mirror to be momentarily active on two servers at the same time? This question has come about from Xen virtual host live migrations. Consider the case with shared storage between two servers: Server A: /dev/md0 is raid1 to devices /dev/mapper/wwidX and

Re: [PATCH] md: Fix data corruption when a degraded raid5 array is reshaped.

2008-01-03 Thread Neil Brown
On Thursday January 3, [EMAIL PROTECTED] wrote: On closer look the safer test is: !test_bit(STRIPE_OP_COMPUTE_BLK, sh-ops.pending). The 'req_compute' field only indicates that a 'compute_block' operation was requested during this pass through handle_stripe so that we can issue a