Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1163128AbbKTPg6 (ORCPT ); Fri, 20 Nov 2015 10:36:58 -0500 Received: from smtp.citrix.com ([66.165.176.89]:41777 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759542AbbKTPg5 (ORCPT ); Fri, 20 Nov 2015 10:36:57 -0500 X-IronPort-AV: E=Sophos;i="5.20,323,1444694400"; d="scan'208";a="313669708" Date: Fri, 20 Nov 2015 15:36:39 +0000 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Boris Ostrovsky CC: Stefano Stabellini , , , , , , , , , , , Catalin Marinas , "Will Deacon" Subject: Re: [PATCH v2] xen/events: Always allocate legacy interrupts on PV guests In-Reply-To: <564F397A.8010203@oracle.com> Message-ID: References: <1447870445-17199-1-git-send-email-boris.ostrovsky@oracle.com> <564F397A.8010203@oracle.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-DLP: MIA1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4295 Lines: 109 On Fri, 20 Nov 2015, Boris Ostrovsky wrote: > On 11/20/2015 06:24 AM, Stefano Stabellini wrote: > > On Wed, 18 Nov 2015, Boris Ostrovsky wrote: > > > After commit 8c058b0b9c34 ("x86/irq: Probe for PIC presence before > > > allocating descs for legacy IRQs") early_irq_init() will no longer > > > preallocate descriptors for legacy interrupts if PIC does not > > > exist, which is the case for Xen PV guests. > > > > > > Therefore we may need to allocate those descriptors ourselves. > > > > > > Signed-off-by: Boris Ostrovsky > > > Suggested-by: Thomas Gleixner > > You need to do this for arm64 too. > > > > FYI you can download arm64 cross-compilers from > > https://releases.linaro.org/14.04/components/toolchain/binaries/ > > then you can use them by exporting ARCH=arm64 and > > CROSS_COMPILE=/path/to/gcc-linaro-aarch64-linux-gnu-version/bin/aarch64-linux-gnu- > > I did test on arm but didn't realize that arm64 uses different include files. > > Does arm64 not have any legacy interrupts? > > BTW, I got this build error: > > STUBCPY drivers/firmware/efi/libstub/lib-sort.stub.o > 0000000000000000 R_AARCH64_ABS64 __efistub_sort > 0000000000000008 R_AARCH64_ABS64 .init__ksymtab_strings > drivers/firmware/efi/libstub/lib-sort.stub.o: absolute symbol references not > allowed in the EFI stub > drivers/firmware/efi/libstub/Makefile:63: recipe for target > 'drivers/firmware/efi/libstub/lib-sort.stub.o' failed > make[4]: *** [drivers/firmware/efi/libstub/lib-sort.stub.o] Error 1 > scripts/Makefile.build:403: recipe for target 'drivers/firmware/efi/libstub' > failed > make[3]: *** [drivers/firmware/efi/libstub] Error 2 > scripts/Makefile.build:403: recipe for target 'drivers/firmware/efi' failed > make[2]: *** [drivers/firmware/efi] Error 2 > scripts/Makefile.build:403: recipe for target 'drivers/firmware' failed > make[1]: *** [drivers/firmware] Error 2 > Makefile:943: recipe for target 'drivers' failed > make: *** [drivers] Error 2 > > I worked around this by removing some of EFI config options but presumably > this needs to be properly fixed. Interesting. This build error could be something new. Could you please post your kernel config? > > > v2: Use nr_legacy_irqs() instead of NR_IRQS_LEGACY (needs definition for > > > ARM) > > > > > > arch/arm/include/asm/irq.h | 4 ++++ > > > drivers/xen/events/events_base.c | 5 +++-- > > > 2 files changed, 7 insertions(+), 2 deletions(-) > > > > > > diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h > > > index be1d07d..b864f60 100644 > > > --- a/arch/arm/include/asm/irq.h > > > +++ b/arch/arm/include/asm/irq.h > > > @@ -2,6 +2,10 @@ > > > #define __ASM_ARM_IRQ_H > > > #define NR_IRQS_LEGACY 16 > > > +static inline int nr_legacy_irqs(void) > > > +{ > > > + return NR_IRQS_LEGACY; > > > +} > > > #ifndef CONFIG_SPARSE_IRQ > > > #include > > > diff --git a/drivers/xen/events/events_base.c > > > b/drivers/xen/events/events_base.c > > > index 849500e..524c221 100644 > > > --- a/drivers/xen/events/events_base.c > > > +++ b/drivers/xen/events/events_base.c > > > @@ -39,6 +39,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > #include > > > #endif > > > #include > > > @@ -420,7 +421,7 @@ static int __must_check xen_allocate_irq_gsi(unsigned > > > gsi) > > > return xen_allocate_irq_dynamic(); > > > /* Legacy IRQ descriptors are already allocated by the arch. > > > */ > > > - if (gsi < NR_IRQS_LEGACY) > > > + if (gsi < nr_legacy_irqs()) > > > irq = gsi; > > > else > > > irq = irq_alloc_desc_at(gsi, -1); > > > @@ -446,7 +447,7 @@ static void xen_free_irq(unsigned irq) > > > kfree(info); > > > /* Legacy IRQ descriptors are managed by the arch. */ > > > - if (irq < NR_IRQS_LEGACY) > > > + if (irq < nr_legacy_irqs()) > > > return; > > > irq_free_desc(irq); > > > -- > > > 2.1.0 > > > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/