From: "Jan Beulich" <JBeulich@suse.com>
To: "Chao Gao" <chao.gao@intel.com>
Cc: Sergey Dyasli <sergey.dyasli@citrix.com>,
Ashok Raj <ashok.raj@intel.com>, WeiLiu <wl@xen.org>,
Andrew Cooper <andrew.cooper3@citrix.com>,
xen-devel <xen-devel@lists.xenproject.org>,
Roger Pau Monne <roger.pau@citrix.com>
Subject: Re: [Xen-devel] [PATCH v7 02/10] microcode/intel: extend microcode_update_match()
Date: Tue, 04 Jun 2019 08:39:15 -0600 [thread overview]
Message-ID: <5CF682930200007800235268@prv1-mh.provo.novell.com> (raw)
In-Reply-To: <1558945891-3015-3-git-send-email-chao.gao@intel.com>
>>> On 27.05.19 at 10:31, <chao.gao@intel.com> wrote:
> --- a/xen/arch/x86/microcode_intel.c
> +++ b/xen/arch/x86/microcode_intel.c
> @@ -134,14 +134,28 @@ static int collect_cpu_info(unsigned int cpu_num, struct cpu_signature *csig)
> return 0;
> }
>
> -static inline int microcode_update_match(
> - unsigned int cpu_num, const struct microcode_header_intel *mc_header,
> - int sig, int pf)
> +static enum microcode_match_result microcode_update_match(
> + const struct microcode_header_intel *mc_header, unsigned int sig,
> + unsigned int pf, unsigned int rev)
> {
> - struct ucode_cpu_info *uci = &per_cpu(ucode_cpu_info, cpu_num);
> + const struct extended_sigtable *ext_header;
> + const struct extended_signature *ext_sig;
> + unsigned long data_size = get_datasize(mc_header);
> + unsigned int i;
> +
> + if ( sigmatch(sig, mc_header->sig, pf, mc_header->pf) )
> + return (mc_header->rev > rev) ? NEW_UCODE : OLD_UCODE;
As indicated before, I think you would better also provide an "equal"
indication. Iirc I've told you that I have one system where the cores
get handed over from the BIOS in an inconsistent state (only core
has ucode loaded). Hence we'd want to be able to also _store_
ucode matching that found on CPU 0, without actually want to _load_
it there.
> - return (sigmatch(sig, uci->cpu_sig.sig, pf, uci->cpu_sig.pf) &&
> - (mc_header->rev > uci->cpu_sig.rev));
> + if ( get_totalsize(mc_header) == (data_size + MC_HEADER_SIZE) )
> + return MIS_UCODE;
Okay, you're tightening the original <= to == here. But if you're
already tightening things, why don't you make sure you actually
have enough data to ...
> + ext_header = (const void *)(mc_header + 1) + data_size;
... hold an extended header, and then also to hold ...
> + ext_sig = (const void *)(ext_header + 1);
> + for ( i = 0; i < ext_header->count; i++ )
> + if ( sigmatch(sig, ext_sig[i].sig, pf, ext_sig[i].pf) )
> + return (mc_header->rev > rev) ? NEW_UCODE : OLD_UCODE;
... enough array elements?
Jan
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next prev parent reply other threads:[~2019-06-04 14:39 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-27 8:31 [PATCH v7 00/10] improve late microcode loading Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-05-27 8:31 ` [PATCH v7 01/10] misc/xen-ucode: Upload a microcode blob to the hypervisor Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-04 16:14 ` Andrew Cooper
2019-06-04 16:23 ` Jan Beulich
2019-06-06 2:29 ` Chao Gao
2019-05-27 8:31 ` [PATCH v7 02/10] microcode/intel: extend microcode_update_match() Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-04 14:39 ` Jan Beulich [this message]
2019-06-05 13:22 ` Roger Pau Monné
2019-06-05 14:16 ` Jan Beulich
2019-06-06 8:26 ` Chao Gao
2019-06-06 9:01 ` Jan Beulich
2019-05-27 8:31 ` [PATCH v7 03/10] microcode: introduce a global cache of ucode patch Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-04 15:03 ` Jan Beulich
2019-06-10 5:33 ` Chao Gao
2019-06-11 6:50 ` Jan Beulich
2019-05-27 8:31 ` [PATCH v7 04/10] microcode: remove struct ucode_cpu_info Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-04 15:13 ` Jan Beulich
2019-06-10 7:19 ` Chao Gao
2019-05-27 8:31 ` [PATCH v7 05/10] microcode: remove pointless 'cpu' parameter Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-04 15:29 ` Jan Beulich
2019-06-10 7:31 ` Chao Gao
2019-05-27 8:31 ` [PATCH v7 06/10] microcode: split out apply_microcode() from cpu_request_microcode() Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-05 12:37 ` Jan Beulich
2019-06-11 3:32 ` Chao Gao
2019-06-11 7:08 ` Jan Beulich
2019-06-11 8:53 ` Chao Gao
2019-06-11 9:15 ` Jan Beulich
2019-05-27 8:31 ` [PATCH v7 07/10] microcode/intel: Writeback and invalidate caches before updating microcode Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-05 13:20 ` Jan Beulich
2019-05-27 8:31 ` [PATCH v7 08/10] x86/microcode: Synchronize late microcode loading Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-05 14:09 ` Jan Beulich
2019-06-11 12:36 ` Chao Gao
2019-06-11 12:58 ` Jan Beulich
2019-06-11 15:47 ` Raj, Ashok
2019-06-05 14:42 ` Roger Pau Monné
2019-05-27 8:31 ` [PATCH v7 09/10] microcode: remove microcode_update_lock Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-05 14:52 ` Roger Pau Monné
2019-06-05 15:15 ` Jan Beulich
2019-06-05 14:53 ` Jan Beulich
2019-06-11 12:46 ` Chao Gao
2019-06-11 13:23 ` Jan Beulich
2019-06-11 16:04 ` Raj, Ashok
2019-06-12 7:38 ` Jan Beulich
2019-06-13 14:05 ` Chao Gao
2019-06-13 14:08 ` Jan Beulich
2019-06-13 14:58 ` Chao Gao
2019-06-13 17:47 ` Raj, Ashok
2019-06-14 8:58 ` Jan Beulich
2019-05-27 8:31 ` [PATCH v7 10/10] x86/microcode: always collect_cpu_info() during boot Chao Gao
2019-05-27 8:31 ` [Xen-devel] " Chao Gao
2019-06-05 14:56 ` Roger Pau Monné
2019-06-11 13:02 ` Chao Gao
2019-06-05 15:05 ` Jan Beulich
2019-06-11 12:58 ` Chao Gao
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