From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vc0-x232.google.com (mail-vc0-x232.google.com [IPv6:2607:f8b0:400c:c03::232]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id C95351A015B for ; Sat, 6 Sep 2014 01:33:15 +1000 (EST) Received: by mail-vc0-f178.google.com with SMTP id la4so12531776vcb.37 for ; Fri, 05 Sep 2014 08:33:12 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <5409C3C6.90204@linux.vnet.ibm.com> References: <1409908577-10648-1-git-send-email-bharata.rao@gmail.com> <5409C3C6.90204@linux.vnet.ibm.com> Date: Fri, 5 Sep 2014 21:03:11 +0530 Message-ID: Subject: Re: [PATCH] pseries: Make CPU hotplug path endian safe From: Bharata B Rao To: Nathan Fontenot Content-Type: text/plain; charset=UTF-8 Cc: linuxppc-dev , "linux-kernel@vger.kernel.org" , Bharata B Rao List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Sep 5, 2014 at 7:38 PM, Nathan Fontenot wrote: > On 09/05/2014 04:16 AM, bharata.rao@gmail.com wrote: >> From: Bharata B Rao >> >> - ibm,rtas-configure-connector should treat the RTAS data as big endian. >> - Treat ibm,ppc-interrupt-server#s as big-endian when setting >> smp_processor_id during hotplug. >> >> Signed-off-by: Bharata B Rao >> --- >> arch/powerpc/platforms/pseries/dlpar.c | 10 +++++----- >> arch/powerpc/platforms/pseries/hotplug-cpu.c | 4 ++-- >> 2 files changed, 7 insertions(+), 7 deletions(-) >> >> diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c >> index 2d0b4d6..dc55f9c 100644 >> --- a/arch/powerpc/platforms/pseries/dlpar.c >> +++ b/arch/powerpc/platforms/pseries/dlpar.c >> @@ -48,11 +48,11 @@ static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa) >> if (!prop) >> return NULL; >> >> - name = (char *)ccwa + ccwa->name_offset; >> + name = (char *)ccwa + be32_to_cpu(ccwa->name_offset); >> prop->name = kstrdup(name, GFP_KERNEL); >> >> - prop->length = ccwa->prop_length; >> - value = (char *)ccwa + ccwa->prop_offset; >> + prop->length = be32_to_cpu(ccwa->prop_length); >> + value = (char *)ccwa + be32_to_cpu(ccwa->prop_offset); >> prop->value = kmemdup(value, prop->length, GFP_KERNEL); >> if (!prop->value) { >> dlpar_free_cc_property(prop); >> @@ -78,7 +78,7 @@ static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa, >> if (!dn) >> return NULL; >> >> - name = (char *)ccwa + ccwa->name_offset; >> + name = (char *)ccwa + be32_to_cpu(ccwa->name_offset); >> dn->full_name = kasprintf(GFP_KERNEL, "%s/%s", path, name); >> if (!dn->full_name) { >> kfree(dn); >> @@ -148,7 +148,7 @@ struct device_node *dlpar_configure_connector(u32 drc_index, >> return NULL; >> >> ccwa = (struct cc_workarea *)&data_buf[0]; >> - ccwa->drc_index = drc_index; >> + ccwa->drc_index = cpu_to_be32(drc_index); > > I need to look at this some more but I think this may cause an issue for > partition migration. If I am following the code correctly, starting in > pseries_devicetree_update(), the drc_index value passed to > dlpar_configure_connector is pulled directly out of a buffer we get from > firmware. This would mean the drc_index value is already in BE format. Yes I see that now. > > Whereas for cpu hotplug the drc_index value is passed in from userspace > via the cpu probe interface in sysfs. I assume that you are seeing the > drc_index value getting passed in in LE format. Yes I am seeing drc_index in LE format for an LE guest during CPU hotplug operation. Regards, Bharata.