Commit-ID: 6a92b11169a65b3f8cc512c75a252cbd0d096ba0 Gitweb: https://git.kernel.org/tip/6a92b11169a65b3f8cc512c75a252cbd0d096ba0 Author: Boris Ostrovsky <[email protected]> AuthorDate: Tue, 11 Sep 2018 15:55:38 -0400 Committer: Thomas Gleixner <[email protected]> CommitDate: Tue, 11 Sep 2018 23:36:50 +0200
x86/EISA: Don't probe EISA bus for Xen PV guests For unprivileged Xen PV guests this is normal memory and ioremap will not be able to properly map it. While at it, since ioremap may return NULL, add a test for pointer's validity. Reported-by: Andy Smith <[email protected]> Signed-off-by: Boris Ostrovsky <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] --- arch/x86/kernel/eisa.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/eisa.c b/arch/x86/kernel/eisa.c index f260e452e4f8..e8c8c5d78dbd 100644 --- a/arch/x86/kernel/eisa.c +++ b/arch/x86/kernel/eisa.c @@ -7,11 +7,17 @@ #include <linux/eisa.h> #include <linux/io.h> +#include <xen/xen.h> + static __init int eisa_bus_probe(void) { - void __iomem *p = ioremap(0x0FFFD9, 4); + void __iomem *p; + + if (xen_pv_domain() && !xen_initial_domain()) + return 0; - if (readl(p) == 'E' + ('I'<<8) + ('S'<<16) + ('A'<<24)) + p = ioremap(0x0FFFD9, 4); + if (p && readl(p) == 'E' + ('I' << 8) + ('S' << 16) + ('A' << 24)) EISA_bus = 1; iounmap(p); return 0;
