From: Chao Gao <chao.gao@intel.com>
To: Jan Beulich <jbeulich@suse.com>
Cc: "Sergey Dyasli" <sergey.dyasli@citrix.com>,
"Ashok Raj" <ashok.raj@intel.com>, "Wei Liu" <wl@xen.org>,
"Andrew Cooper" <andrew.cooper3@citrix.com>,
xen-devel@lists.xenproject.org,
"Roger Pau Monné" <roger.pau@citrix.com>
Subject: Re: [Xen-devel] [PATCH v10 15/16] microcode: disable late loading if CPUs are affected by BDF90
Date: Tue, 17 Sep 2019 17:01:28 +0800 [thread overview]
Message-ID: <20190917090128.GB10190@gao-cwp> (raw)
In-Reply-To: <f5d22eed-42c0-5d99-7adc-a46ac52a9639@suse.com>
On Fri, Sep 13, 2019 at 11:22:59AM +0200, Jan Beulich wrote:
>On 12.09.2019 09:22, Chao Gao wrote:
>> @@ -283,6 +284,27 @@ static enum microcode_match_result compare_patch(
>> : OLD_UCODE;
>> }
>>
>> +static bool is_blacklisted(void)
>> +{
>> + struct cpuinfo_x86 *c = ¤t_cpu_data;
>> + uint64_t llc_size = c->x86_cache_size * 1024ULL;
>> + struct cpu_signature *sig = &this_cpu(cpu_sig);
>> +
>> + do_div(llc_size, c->x86_max_cores);
>> +
>> + /*
>> + * Late loading on model 79 with microcode revision less than 0x0b000021
>> + * and LLC size per core bigger than 2.5MB may result in a system hang.
>> + * This behavior is documented in item BDF90, #334165 (Intel Xeon
>> + * Processor E7-8800/4800 v4 Product Family).
>> + */
>> + if ( c->x86 == 6 && c->x86_model == 0x4F && c->x86_mask == 0x1 &&
>> + llc_size > 2621440 && sig->rev < 0x0b000021 )
>> + return true;
>> +
>> + return false;
>> +}
>
>Isn't this misbehavior worked around by the wbinvd() you add in the next
>patch?
Hi Jan and Andrew,
Perhaps I misunderstood what I was told. I am confirming with Ashok
whether this patch is necessary.
>
>> --- a/xen/include/asm-x86/microcode.h
>> +++ b/xen/include/asm-x86/microcode.h
>> @@ -30,6 +30,7 @@ struct microcode_ops {
>> bool (*match_cpu)(const struct microcode_patch *patch);
>> enum microcode_match_result (*compare_patch)(
>> const struct microcode_patch *new, const struct microcode_patch *old);
>> + bool (*is_blacklisted)(void);
>
>Why a hook rather than a boolean flag, which could be set by
>microcode_update_one() (as invoked during AP bringup)?
How about set the boolean flag in Intel_errata_workarounds?
One limitation of setting the flag in microcode_update_one() is:
BSP also calls microcode_update_one(). But calculating LLC size per
core on BSP would meet the same issue as the following patch
(i.e. patch 16/16): BSP's current_cpu_data isn't initialized
properly. We might need to revert commit f97838bbd980a01 in
some way and reenumerate features after ucode loading is done.
Thanks
Chao
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next prev parent reply other threads:[~2019-09-17 8:57 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-12 7:22 [Xen-devel] [PATCH v10 00/16] improve late microcode loading Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 01/16] microcode/intel: extend microcode_update_match() Chao Gao
2019-09-12 10:24 ` Jan Beulich
2019-09-13 6:50 ` Jan Beulich
2019-09-13 7:02 ` Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 02/16] microcode/amd: distinguish old and mismatched ucode in microcode_fits() Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 03/16] microcode: introduce a global cache of ucode patch Chao Gao
2019-09-12 10:29 ` Jan Beulich
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 04/16] microcode: clean up microcode_resume_cpu Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 05/16] microcode: remove struct ucode_cpu_info Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 06/16] microcode: remove pointless 'cpu' parameter Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 07/16] microcode/amd: call svm_host_osvw_init() in common code Chao Gao
2019-09-12 12:34 ` Jan Beulich
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 08/16] microcode: pass a patch pointer to apply_microcode() Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 09/16] microcode: split out apply_microcode() from cpu_request_microcode() Chao Gao
2019-09-12 14:07 ` Jan Beulich
2019-09-13 6:47 ` Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 10/16] microcode: unify ucode loading during system bootup and resuming Chao Gao
2019-09-12 14:59 ` Jan Beulich
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 11/16] microcode: reduce memory allocation and copy when creating a patch Chao Gao
2019-09-12 15:04 ` Jan Beulich
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 12/16] x86/microcode: Synchronize late microcode loading Chao Gao
2019-09-12 15:32 ` Jan Beulich
2019-09-13 7:01 ` Chao Gao
2019-09-13 7:15 ` Jan Beulich
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 13/16] microcode: remove microcode_update_lock Chao Gao
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 14/16] microcode: rendezvous CPUs in NMI handler and load ucode Chao Gao
2019-09-13 9:14 ` Jan Beulich
2019-09-16 3:18 ` Chao Gao
2019-09-16 8:22 ` Jan Beulich
2019-09-13 9:18 ` Jan Beulich
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 15/16] microcode: disable late loading if CPUs are affected by BDF90 Chao Gao
2019-09-13 9:22 ` Jan Beulich
2019-09-17 9:01 ` Chao Gao [this message]
2019-09-17 10:49 ` Jan Beulich
2019-09-13 12:23 ` Andrew Cooper
2019-09-12 7:22 ` [Xen-devel] [PATCH v10 16/16] microcode/intel: writeback and invalidate cache conditionally Chao Gao
2019-09-13 9:32 ` Jan Beulich
2019-09-13 8:47 ` [Xen-devel] [PATCH v10 00/16] improve late microcode loading Jan Beulich
2019-09-17 7:09 ` Chao Gao
2019-09-17 7:11 ` Jan Beulich
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