From: Andreas Deresch Date: Sun, 26 Feb 2006 03:18:34 +0000 (+0100) Subject: [PATCH] i386: Handle non existing APICs without panicing X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=6070f9ec6b03cc46cd0242523326f7a296f47c1c;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git [PATCH] i386: Handle non existing APICs without panicing [description from AK] This fixes booting in APIC mode on some ACER laptops. x86-64 did a similar change some time ago. See http://bugzilla.kernel.org/show_bug.cgi?id=4700 for details Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c index f2dd218d88cb..235822b3f41b 100644 --- a/arch/i386/kernel/io_apic.c +++ b/arch/i386/kernel/io_apic.c @@ -2566,8 +2566,10 @@ int __init io_apic_get_unique_id (int ioapic, int apic_id) spin_unlock_irqrestore(&ioapic_lock, flags); /* Sanity check */ - if (reg_00.bits.ID != apic_id) - panic("IOAPIC[%d]: Unable change apic_id!\n", ioapic); + if (reg_00.bits.ID != apic_id) { + printk("IOAPIC[%d]: Unable to change apic_id!\n", ioapic); + return -1; + } } apic_printk(APIC_VERBOSE, KERN_INFO diff --git a/arch/i386/kernel/mpparse.c b/arch/i386/kernel/mpparse.c index e7609abf3796..e6e2f43db85e 100644 --- a/arch/i386/kernel/mpparse.c +++ b/arch/i386/kernel/mpparse.c @@ -915,6 +915,7 @@ void __init mp_register_ioapic ( u32 gsi_base) { int idx = 0; + int tmpid; if (nr_ioapics >= MAX_IO_APICS) { printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded " @@ -935,9 +936,14 @@ void __init mp_register_ioapic ( set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address); if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 < 15)) - mp_ioapics[idx].mpc_apicid = io_apic_get_unique_id(idx, id); + tmpid = io_apic_get_unique_id(idx, id); else - mp_ioapics[idx].mpc_apicid = id; + tmpid = id; + if (tmpid == -1) { + nr_ioapics--; + return; + } + mp_ioapics[idx].mpc_apicid = tmpid; mp_ioapics[idx].mpc_apicver = io_apic_get_version(idx); /*