2018-01-19 10:07:58

by Jan Kiszka

Subject: [PATCH] x86/jailhouse: Respect pci=lastbus command line settings

Limiting the scan width to the known last bus via the command line can
accelerate the boot noteworthy.

Signed-off-by: Jan Kiszka <[email protected]>
---
arch/x86/kernel/jailhouse.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c
index 2b7ebbe9043d..b68fd895235a 100644
--- a/arch/x86/kernel/jailhouse.c
+++ b/arch/x86/kernel/jailhouse.c
@@ -119,8 +119,10 @@ static int __init jailhouse_pci_arch_init(void)
/*
* There are no bridges on the virtual PCI root bus under Jailhouse,
* thus no other way to discover all devices than a full scan.
+ * Respect any overrides via the command line, though.
*/
- pcibios_last_bus = 0xff;
+ if (pcibios_last_bus < 0)
+ pcibios_last_bus = 0xff;

return 0;
}

2018-01-20 07:23:07

by tip-bot for Vasyl Gomonovych

Subject: [tip:x86/platform] x86/jailhouse: Respect pci=lastbus command line settings

Commit-ID: 3b42349d56c96e144401d2317d8eeb9937511423
Gitweb: https://git.kernel.org/tip/3b42349d56c96e144401d2317d8eeb9937511423
Author: Jan Kiszka <[email protected]>
AuthorDate: Fri, 19 Jan 2018 11:06:30 +0100
Committer: Thomas Gleixner <[email protected]>
CommitDate: Sat, 20 Jan 2018 08:15:44 +0100

x86/jailhouse: Respect pci=lastbus command line settings

Limiting the scan width to the known last bus via the command line can
accelerate the boot noteworthy.

Signed-off-by: Jan Kiszka <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Jailhouse <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

---
arch/x86/kernel/jailhouse.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c
index 2b7ebbe..b68fd89 100644
--- a/arch/x86/kernel/jailhouse.c
+++ b/arch/x86/kernel/jailhouse.c
@@ -119,8 +119,10 @@ static int __init jailhouse_pci_arch_init(void)
/*
* There are no bridges on the virtual PCI root bus under Jailhouse,
* thus no other way to discover all devices than a full scan.
+ * Respect any overrides via the command line, though.
*/
- pcibios_last_bus = 0xff;
+ if (pcibios_last_bus < 0)
+ pcibios_last_bus = 0xff;

return 0;
}