[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH] xen/CET: Fix __initconst_cf_clobber
- To: Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx>
- From: Jan Beulich <jbeulich@xxxxxxxx>
- Date: Thu, 3 Mar 2022 11:41:24 +0100
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=suse.com; dmarc=pass action=none header.from=suse.com; dkim=pass header.d=suse.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ocrnWVGVJseQsq/tw8U64QEYWft8t5ClbHcEqgkCQsM=; b=g0ZaryL1wJjgoz3ozcI7TLjsUAMYAAYtmgRweK3H9Q0tixSav+J3UeJlJGbXOiYnjefVtVhsNBV0xT+7U4OCPLhbtkNI29LSxN8oItiPbsg0Af8KBxynXT46EarK4G/3EKcQglh6SavYqmj8EuyVOrYtLu6+jxbe33a3qGaOIP7xI8lm9BfnX9/0I9pcBVpGiP18czz28IdIsxhUgrOWdOtdpVqDUbqwJSkW7FNZ/B6EGUJwNObQukYA809Jo3a/6GDBTYx7qwGaWPDvQ/Oru7/mONXzUzaCWmyxEM03GBjVwFZ4tg+dIkv2qiyqVIhw5/8H395p//4dDAJoFh24Mg==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=SMlIdcru6duqfH/UbH3LdgEa4tYbLz4Y0dlAfUEIi9fY32YM4V6vng2WIL+1UwrOfS7IAll9ISJ6fN6jV55+/f3nF/zXwZaliOJycZ87qJdsVXRh3VR3zpeZ6FSSRZphjCvwaILrylrDRxjkerH7NW712KlkIxSFRwg+g5XH+2qOIe1ETfNv34NnqizjvkZIX0pBMvHUiO4jCTL2BPkeCCaP7rJ+70yvsDr7d6WWNKcwPap0WJ8riOjG3AflWAUH7uoeIvJO/a2WgvA/tHUGwa/tWVdOwN9j2zAn+GWPC+tJ8gkBfusevbXXj6j8v2An8JJ3XBznBA+oTX1jroqxUQ==
- Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=suse.com;
- Cc: Roger Pau Monne <roger.pau@xxxxxxxxxx>, Wei Liu <wl@xxxxxxx>, Xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxxx>
- Delivery-date: Thu, 03 Mar 2022 10:41:36 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 03.03.2022 11:29, Andrew Cooper wrote:
> On 03/03/2022 07:35, Jan Beulich wrote:
>> On 02.03.2022 23:10, Andrew Cooper wrote:
>>> --- a/xen/arch/x86/xen.lds.S
>>> +++ b/xen/arch/x86/xen.lds.S
>>> @@ -210,6 +210,12 @@ SECTIONS
>>> DECL_SECTION(.init.data) {
>>> #endif
>>>
>>> + . = ALIGN(POINTER_ALIGN);
>>> + __initdata_cf_clobber_start = .;
>>> + *(.init.data.cf_clobber)
>>> + *(.init.rodata.cf_clobber)
>>> + __initdata_cf_clobber_end = .;
>>> +
>>> *(.init.rodata)
>>> *(.init.rodata.*)
>> I wonder if this shouldn't really be two sections. Live-patching will
>> need to supply two ranges to apply_alternatives() anyway (one for each
>> section, unless you want to start requiring to pass a linker script to
>> "$(LD) -r" when generating live patches, just to fold the two sections),
>> so in the core hypervisor we may want to follow suit.
>
> I don't see why livepatches would need two sections - they're linked in
> a similar way to Xen IIRC. Either way, if changes are needed, they
> should be part of the livepatch work.
Live patch objects being relocatable ones, their loading logic works with
section boundaries. Hence there'll be two sections of interest, the
boundaries of which are independent and hence need passing as separate
values.
Jan
|
