From: Dave Hansen <dave.hansen@intel.com>
To: Mike Rapoport <rppt@kernel.org>
Cc: Changyuan Lyu <changyuanl@google.com>,
linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
anthony.yznaga@oracle.com, arnd@arndb.de, ashish.kalra@amd.com,
benh@kernel.crashing.org, bp@alien8.de, catalin.marinas@arm.com,
corbet@lwn.net, dave.hansen@linux.intel.com,
devicetree@vger.kernel.org, dwmw2@infradead.org,
ebiederm@xmission.com, graf@amazon.com, hpa@zytor.com,
jgowans@amazon.com, kexec@lists.infradead.org, krzk@kernel.org,
linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org,
linux-mm@kvack.org, luto@kernel.org, mark.rutland@arm.com,
mingo@redhat.com, pasha.tatashin@soleen.com, pbonzini@redhat.com,
peterz@infradead.org, ptyadav@amazon.de, robh@kernel.org,
rostedt@goodmis.org, saravanak@google.com,
skinsburskii@linux.microsoft.com, tglx@linutronix.de,
thomas.lendacky@amd.com, will@kernel.org, x86@kernel.org
Subject: Re: [PATCH v7 14/18] x86/boot: make sure KASLR does not step over KHO preserved memory
Date: Fri, 2 May 2025 14:36:25 -0700 [thread overview]
Message-ID: <d6c09132-05bb-481a-93dd-8e9d664981ae@intel.com> (raw)
In-Reply-To: <aBU2JQRKXjqoFClQ@kernel.org>
On 5/2/25 14:16, Mike Rapoport wrote:
>>> +/*
>>> + * If KHO is active, only process its scratch areas to ensure we are not
>>> + * stepping onto preserved memory.
>>> + */
>>> +#ifdef CONFIG_KEXEC_HANDOVER
>>> +static bool process_kho_entries(unsigned long minimum, unsigned long image_size)
>>> +{
>> I thought we agreed to rework this to unconditionally define the
>> kho_scratch structures so the #ifdef can go away?
> It's either #ifdef or double casting and my understanding was that your
> preference was to get rid of the double casting.
Looking back at the other message... Sorry, you did make it clear there
and it just didn't penetrate my thick skull.
The double cast is goofy, but it does seem to be the normal way of doing
things. There are lots of examples of it. So, grudgingly, I prefer the
double cast over the #ifdef.
BTW, _please_ changelog this stuff. It would have saved this round of
back-and-forth. The changelog is the perfect place to say something like:
This looks goofy out of context, but it is unfortunately the way
that this is handled across the tree. There are at least a dozen
instances of casting like this.
This series is generally a bit sparse in the changelog and comment
departments.
next prev parent reply other threads:[~2025-05-02 21:36 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-05-01 22:54 [PATCH v7 00/18] kexec: introduce Kexec HandOver (KHO) Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 01/18] memblock: add MEMBLOCK_RSRV_KERN flag Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 02/18] memblock: Add support for scratch memory Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 03/18] memblock: introduce memmap_init_kho_scratch() Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 04/18] kexec: add Kexec HandOver (KHO) generation helpers Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 05/18] kexec: add KHO parsing support Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 06/18] kexec: include asm/early_ioremap.h Changyuan Lyu
2025-05-02 0:35 ` Andrew Morton
2025-05-02 18:37 ` Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 07/18] kexec: enable KHO support for memory preservation Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 08/18] kexec: add KHO support to kexec file loads Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 09/18] kexec: add config option for KHO Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 10/18] arm64: add KHO support Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 11/18] x86/setup: use memblock_reserve_kern for memory used by kernel Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 12/18] x86/kexec: add support for passing kexec handover (KHO) data Changyuan Lyu
2025-05-02 18:39 ` Dave Hansen
2025-05-01 22:54 ` [PATCH v7 13/18] x86/e820: temporarily enable KHO scratch for memory below 1M Changyuan Lyu
2025-05-02 18:39 ` Dave Hansen
2025-05-01 22:54 ` [PATCH v7 14/18] x86/boot: make sure KASLR does not step over KHO preserved memory Changyuan Lyu
2025-05-02 18:48 ` Dave Hansen
2025-05-02 21:16 ` Mike Rapoport
2025-05-02 21:36 ` Dave Hansen [this message]
2025-05-05 20:07 ` Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 15/18] x86/Kconfig: enable kexec handover for 64 bits Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 16/18] memblock: add KHO support for reserve_mem Changyuan Lyu
2025-05-01 22:54 ` [PATCH v7 17/18] Documentation: add documentation for KHO Changyuan Lyu
2025-05-06 2:31 ` Bagas Sanjaya
2025-05-07 17:38 ` Changyuan Lyu
2025-05-07 23:54 ` Bagas Sanjaya
2025-05-01 22:54 ` [PATCH v7 18/18] Documentation: KHO: Add memblock bindings Changyuan Lyu
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