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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: dkf4pnmgmr8yiy9rqubo3r7zz89mocy6 X-Rspam-User: X-Rspamd-Queue-Id: 629608000B X-Rspamd-Server: rspam06 X-HE-Tag: 1679574631-351299 X-HE-Meta: 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 89iX3Owr gzsne1O00S1MP5Pqt4HF0sluow89K1YyP1SopzvpvX2Srvax8KK8yvaTCnm4rC8ySBKU9lpdBeLyzbjIkjkEm0EV3CofpIB0Il4NZpV+vSbMd9jfuWdFvmUWwkoXIlRwN/LU6dIWqb5SS1x9CK4fpYszNVFBXa7E+hx04UP5cZntOx7j5aALCFD1jh6gs/1heOPnuzZ3uRVGELRmaBGHqEuzTQ0oPQYV2WG5ntz+MJUzgA9DHqWyljpImaFMPMIb9dPRm0/ZJBvZPIo/DpHvOLlZzXa/Rg1M9QpGKHuNIHN4W3olu2dInrS5ctesWi0ChXC7VCkmQb7LZKpE5BG4VaNnqx7SnCpKBTMI4y1pPNkLiWLFntqhyCKHmTA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 3/23/23 13:16, Mike Rapoport wrote: > On Thu, Mar 23, 2023 at 12:52:36PM +0100, Alexandre Ghiti wrote: >> On 3/20/23 18:44, Mike Rapoport wrote: >>> On Mon, Mar 20, 2023 at 11:54:14AM +0100, Alexandre Ghiti wrote: >>>> Hi Mike, >>>> >>>> On 3/16/23 21:12, Mike Rapoport wrote: >>>>> Hi Alexandre, >>>>> >>>>> On Thu, Mar 16, 2023 at 02:17:09PM +0100, Alexandre Ghiti wrote: >>>>>> This function allows to split a region in memblock.memory and will be >>>>>> useful when setting up the linear mapping with STRICT_KERNEL_RWX: it >>>>>> allows to isolate the kernel text/rodata and then avoid to map those >>>>>> regions with a PUD/P4D/PGD. >>>>> Sorry I've missed it last time. The changelog is fine in the context of >>>> No worries :) >>>> >>>> >>>>> this series, but if you look at it as a part of memblock changelog it >>>>> doesn't provide enough background on why memblock_isolate_memory() is >>>>> useful. >>>>> >>>>> Can you please add more context so it would be self explanatory? >>>> What about: "memblock.memory contains the list of memory regions and a >>>> memory region can cover memory that will be mapped with different >>>> permissions. So to ease the mapping process, allow to isolate those regions >>>> by introducing a new function called memblock_isolate_memory. This will be >>>> used in arch specific code to isolate the kernel text/rodata regions when >>>> STRICT_KERNEL_RWX is enabled so that we avoid mapping them with PUD/P4D/PGD >>>> mappings." >>> With this change >>> >>> ... STRICT_KERNEL_RWX is enabled so that they can be mapped with base pages. >> >> Actually they will get mapped with PMD mappings :) I'll just append: "or PMD >> mapping" to your sentence above if that's ok with you. > Didn't read the rest of the patches :) > > .. STRICT_KERNEL_RWX is enabled so that they can be mapped with differently > than the rest of the memory. > > Does it cover the usescases? Yes, fine with me! Thanks again > >>> Acked-by: Mike Rapoport (IBM) >> >> Thanks for your review, >> >> Alex >> >> >>>> Thanks, >>>> >>>> Alex >>>> >>>> >>>>>> Signed-off-by: Alexandre Ghiti >>>>>> Reviewed-by: Anup Patel >>>>>> Tested-by: Anup Patel >>>>>> --- >>>>>> include/linux/memblock.h | 1 + >>>>>> mm/memblock.c | 20 ++++++++++++++++++++ >>>>>> 2 files changed, 21 insertions(+) >>>>>> >>>>>> diff --git a/include/linux/memblock.h b/include/linux/memblock.h >>>>>> index 50ad19662a32..2f7ef97c0da7 100644 >>>>>> --- a/include/linux/memblock.h >>>>>> +++ b/include/linux/memblock.h >>>>>> @@ -125,6 +125,7 @@ int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size); >>>>>> int memblock_mark_mirror(phys_addr_t base, phys_addr_t size); >>>>>> int memblock_mark_nomap(phys_addr_t base, phys_addr_t size); >>>>>> int memblock_clear_nomap(phys_addr_t base, phys_addr_t size); >>>>>> +int memblock_isolate_memory(phys_addr_t base, phys_addr_t size); >>>>>> void memblock_free_all(void); >>>>>> void memblock_free(void *ptr, size_t size); >>>>>> diff --git a/mm/memblock.c b/mm/memblock.c >>>>>> index 25fd0626a9e7..e8c651a37012 100644 >>>>>> --- a/mm/memblock.c >>>>>> +++ b/mm/memblock.c >>>>>> @@ -805,6 +805,26 @@ static int __init_memblock memblock_isolate_range(struct memblock_type *type, >>>>>> return 0; >>>>>> } >>>>>> +/** >>>>>> + * memblock_isolate_memory - isolate given range in memblock.memory >>>>>> + * @base: base of range to isolate >>>>>> + * @size: size of range to isolate >>>>>> + * >>>>>> + * Isolates the given range in memblock.memory so that it does not share any >>>>>> + * region with other ranges. >>>>>> + * >>>>>> + * Return: >>>>>> + * 0 on success, -errno on failure. >>>>>> + */ >>>>>> + >>>>>> +int __init_memblock memblock_isolate_memory(phys_addr_t base, phys_addr_t size) >>>>>> +{ >>>>>> + int start_rgn, end_rgn; >>>>>> + >>>>>> + return memblock_isolate_range(&memblock.memory, base, size, >>>>>> + &start_rgn, &end_rgn); >>>>>> +} >>>>>> + >>>>>> static int __init_memblock memblock_remove_range(struct memblock_type *type, >>>>>> phys_addr_t base, phys_addr_t size) >>>>>> { >>>>>> -- >>>>>> 2.37.2 >>>>>>