From: Tianyu Lan <ltykernel@gmail.com>
To: Wei Liu <wei.liu@kernel.org>
Cc: kys@microsoft.com, haiyangz@microsoft.com,
sthemmin@microsoft.com, liuwe@microsoft.com, tglx@linutronix.de,
mingo@redhat.com, bp@alien8.de, hpa@zytor.com, x86@kernel.org,
michael.h.kelley@microsoft.com,
Tianyu Lan <Tianyu.Lan@microsoft.com>,
linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
vkuznets@redhat.com
Subject: Re: [PATCH 2/4] x86/Hyper-V: Free hv_panic_page when fail to register kmsg dump
Date: Thu, 19 Mar 2020 16:12:54 +0800 [thread overview]
Message-ID: <0105c10b-b546-6d93-bb49-e9a4ce4589f6@gmail.com> (raw)
In-Reply-To: <20200317173600.2hqznyabyj4nckjo@debian>
Hi Wei:
Thanks for your review.
On 3/18/2020 1:36 AM, Wei Liu wrote:
> On Tue, Mar 17, 2020 at 06:25:21AM -0700, ltykernel@gmail.com wrote:
>> From: Tianyu Lan <Tianyu.Lan@microsoft.com>
>>
>> If fail to register kmsg dump on Hyper-V platform, hv_panic_page
>> will not be used anywhere. So free and reset it.
>>
>> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
>> ---
>> drivers/hv/vmbus_drv.c | 6 +++++-
>> 1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
>> index b56b9fb9bd90..b043efea092a 100644
>> --- a/drivers/hv/vmbus_drv.c
>> +++ b/drivers/hv/vmbus_drv.c
>> @@ -1385,9 +1385,13 @@ static int vmbus_bus_init(void)
>> hv_panic_page = (void *)hv_alloc_hyperv_zeroed_page();
>> if (hv_panic_page) {
>> ret = kmsg_dump_register(&hv_kmsg_dumper);
>> - if (ret)
>> + if (ret) {
>> pr_err("Hyper-V: kmsg dump register "
>> "error 0x%x\n", ret);
>> + hv_free_hyperv_page(
>> + (unsigned long)hv_panic_page);
>> + hv_panic_page = NULL;
>> + }
>
> While this modification looks correct to me, there is a call to free
> hv_panic_page in the err_alloc path. That makes the error handling a bit
> confusing here.
>
> I think you can just remove that function call in err_alloc path.
OK. Will update in the next version.
>
> Wei.
>
>> } else
>> pr_err("Hyper-V: panic message page memory "
>> "allocation failed");
>> --
>> 2.14.5
>>
next prev parent reply other threads:[~2020-03-19 8:13 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-17 13:25 [PATCH 0/4] x86/Hyper-V: Panic code path fixes ltykernel
2020-03-17 13:25 ` [PATCH 0/4] x86/Hyper-V: Unload vmbus channel in hv panic callback ltykernel
2020-03-17 17:35 ` Wei Liu
2020-03-19 8:24 ` Tianyu Lan
2020-03-18 15:58 ` Vitaly Kuznetsov
2020-03-19 0:33 ` Michael Kelley
2020-03-19 8:03 ` Vitaly Kuznetsov
2020-03-19 15:06 ` Michael Kelley
2020-03-19 8:03 ` Tianyu Lan
2020-03-17 13:25 ` [PATCH 2/4] x86/Hyper-V: Free hv_panic_page when fail to register kmsg dump ltykernel
2020-03-17 17:36 ` Wei Liu
2020-03-19 8:12 ` Tianyu Lan [this message]
2020-03-19 0:38 ` Michael Kelley
2020-03-17 13:25 ` [PATCH 3/4] x86/Hyper-V: Trigger crash enlightenment only once during system crash ltykernel
2020-03-19 0:45 ` Michael Kelley
2020-03-17 13:25 ` [PATCH 4/4] x86/Hyper-V: Report crash register data or ksmg before running crash kernel ltykernel
2020-03-19 0:51 ` Michael Kelley
2020-03-19 0:57 ` [PATCH 0/4] x86/Hyper-V: Panic code path fixes Michael Kelley
2020-03-19 14:08 ` Tianyu Lan
2020-03-19 15:14 ` Michael Kelley
2020-03-19 16:07 ` Michael Kelley
2020-03-20 2:21 ` Tianyu Lan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=0105c10b-b546-6d93-bb49-e9a4ce4589f6@gmail.com \
--to=ltykernel@gmail.com \
--cc=Tianyu.Lan@microsoft.com \
--cc=bp@alien8.de \
--cc=haiyangz@microsoft.com \
--cc=hpa@zytor.com \
--cc=kys@microsoft.com \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=liuwe@microsoft.com \
--cc=michael.h.kelley@microsoft.com \
--cc=mingo@redhat.com \
--cc=sthemmin@microsoft.com \
--cc=tglx@linutronix.de \
--cc=vkuznets@redhat.com \
--cc=wei.liu@kernel.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).