fix: stale read issue when probing#148
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talos-bot merged 1 commit intosiderolabs:v2from Mar 10, 2026
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An utility used to format the partition (e.g. cryptsetup) might open the block device with `O_DIRECT`, so the next read done by the probing code might be hitting the buffer cache, and it doesn't see the writes done by `cryptsetup` (the cache is not coherent). We can't use `O_DIRECT` for I/O, as it has tight requirements for aligning the reads and writes, so instead ask Linux to invalidate the cache before probing. We only probe on blockdevice changes, so it shouldn't cause performance issues. Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>
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This pulls in a fix siderolabs/go-blockdevice#148 Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>
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This pulls in a fix siderolabs/go-blockdevice#148 Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>
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This pulls in a fix siderolabs/go-blockdevice#148 Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com> (cherry picked from commit ad3c59a)
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An utility used to format the partition (e.g. cryptsetup) might open the block device with
O_DIRECT, so the next read done by the probing code might be hitting the buffer cache, and it doesn't see the writes done bycryptsetup(the cache is not coherent).We can't use
O_DIRECTfor I/O, as it has tight requirements for aligning the reads and writes, so instead ask Linux to invalidate the cache before probing.We only probe on blockdevice changes, so it shouldn't cause performance issues.