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coldplug replaces /dev with an empty tmpfs and then relies on asynchronous uevents to recreate device nodes. Reuse the existing mkdev scanner so devices already present in sysfs are available synchronously before the state machine can advance. Because the normal hotplug mknod path may now encounter those nodes with EEXIST, explicitly apply the requested mode to existing nodes before applying any configured group. The regular udevtrigger/hotplug pass still remains authoritative for final permissions and handlers. Signed-off-by: Cao Yuhang <caoyuhang@fwerkor.com>
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Summary
procd_coldplug()replaces/devwith a fresh tmpfs and then depends on asynchronousudevtrigger/hotplug processing to recreate device nodes. This leaves a window where devices already present in sysfs, including the active console tty, do not exist under/dev.In repeated downstream x86_64 QEMU reboot tests on an older procd baseline this reaches
STATE_UBUSbefore the console nodes are available, producing:and the expected
askconsoleshell never appears.Current procd already uses
patch_stdio()after 615e929, so a missing/dev/consolecan fall back to/dev/nullinstead of emitting that exact error. That protects procd's stdio but does not recreate the tty named byconsole=, so the underlying coldplug race foraskconsoleremains.Change
Reuse the existing
mkdev("*")sysfs scanner immediately after remounting/dev, before launchingudevtrigger. Devices that already exist in sysfs are therefore available synchronously.Those precreated nodes initially use the scanner's restrictive mode. The normal hotplug pass remains authoritative:
handle_makedev()now applies the requested mode whenmknod()succeeds or returnsEEXIST, then applies the configured group as before. This preserves the existing modes/groups for nodes such as tty, zero, random and urandom.This follows the same underlying rationale as 6dafa86 (
initd/coldplug: create /dev/null before running udevtrigger), while avoiding more per-device special cases.