From 0ae39cc98192252f756f8943be85e9f4dbd8436e Mon Sep 17 00:00:00 2001 From: "Matwey V. Kornilov" Date: Wed, 27 Aug 2014 12:07:44 +0400 Subject: [PATCH] parport: parport_pc: Implement architecture and device check to cut off false-positives We definitely know that only x86 (32-bit) architecture is affected by the issue, so implement a stub instead of the actual check for other architectures. We also know that motherboard LPT chipset is affected, so the port is either come from parport_pc_init (when `io' module param is used) or parport_pc_find_isa_ports (when default LPT ports are probbed: 0x378, 0x278, 0x3bc). In both cases the port considered as 'legacy' and `dev' member of struct parport is NULL. See also comments for `struct parport' in parport.h Signed-off-by: Matwey V. Kornilov Signed-off-by: Greg Kroah-Hartman --- drivers/parport/parport_pc.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/drivers/parport/parport_pc.c b/drivers/parport/parport_pc.c index fedc06bed18d..f721299eb1ba 100644 --- a/drivers/parport/parport_pc.c +++ b/drivers/parport/parport_pc.c @@ -1702,7 +1702,8 @@ static int parport_ECP_supported(struct parport *pb) } #endif -static int intel_bug_present(struct parport *pb) +#ifdef CONFIG_X86_32 +static int intel_bug_present_check_epp(struct parport *pb) { const struct parport_pc_private *priv = pb->private_data; int bug_present = 0; @@ -1725,6 +1726,21 @@ static int intel_bug_present(struct parport *pb) return bug_present; } +static int intel_bug_present(struct parport *pb) +{ +/* Check whether the device is legacy, not PCI or PCMCIA. Only legacy is known to be affected. */ + if (pb->dev != NULL) { + return 0; + } + + return intel_bug_present_check_epp(pb); +} +#else +static int intel_bug_present(struct parport *pb) +{ + return 0; +} +#endif /* CONFIG_X86_32 */ static int parport_ECPPS2_supported(struct parport *pb) {