From e16b46605960bd071a3e26f316e0bb600ae91e37 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Thu, 21 Jul 2016 21:40:28 -0600 Subject: PCI: Allow additional bus numbers for hotplug bridges A user may hot add a switch requiring more than one bus to enumerate. This previously required a system reboot if BIOS did not sufficiently pad the bus resource, which they frequently don't do. Add a kernel parameter so a user can specify the minimum number of bus numbers to reserve for a hotplug bridge's subordinate buses so rebooting won't be necessary. The default is 1, which is equivalent to previous behavior. Signed-off-by: Keith Busch Signed-off-by: Bjorn Helgaas --- Documentation/kernel-parameters.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 82b42c9..487e799b 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -3016,6 +3016,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. hpmemsize=nn[KMG] The fixed amount of bus space which is reserved for hotplug bridge's memory window. Default size is 2 megabytes. + hpbussize=nn The minimum amount of additional bus numbers + reserved for buses below a hotplug bridge. + Default is 1. realloc= Enable/disable reallocating PCI bridge resources if allocations done by BIOS are too small to accommodate resources required by all child -- cgit v1.1