Le 03/02/2022 à 01:01, Luis Chamberlain a écrit :
> On Sat, Jan 29, 2022 at 05:02:09PM +0000, Christophe Leroy wrote:
>> diff --git a/kernel/module.c b/kernel/module.c
>> index 11f51e17fb9f..f3758115ebaa 100644
>> --- a/kernel/module.c
>> +++ b/kernel/module.c
>> @@ -81,7 +81,9 @@
>> /* If this is set, the section belongs in the init part of the module */
>> #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
>>
>> +#ifndef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
>> #define data_layout core_layout
>> +#endif
>>
>> /*
>> * Mutex protects:
>> @@ -111,6 +113,12 @@ static struct mod_tree_root {
>> #define module_addr_min mod_tree.addr_min
>> #define module_addr_max mod_tree.addr_max
>>
>> +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
>> +static struct mod_tree_root mod_data_tree __cacheline_aligned = {
>> + .addr_min = -1UL,
>> +};
>> +#endif
>> +
>> #ifdef CONFIG_MODULES_TREE_LOOKUP
>>
>> /*
>> @@ -186,6 +194,11 @@ static void mod_tree_insert(struct module *mod)
>> __mod_tree_insert(&mod->core_layout.mtn, &mod_tree);
>> if (mod->init_layout.size)
>> __mod_tree_insert(&mod->init_layout.mtn, &mod_tree);
>> +
>> +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
>> + mod->data_layout.mtn.mod = mod;
>> + __mod_tree_insert(&mod->data_layout.mtn, &mod_data_tree);
>> +#endif
>
>
> kernel/ directory has quite a few files, module.c is the second to
> largest file, and it has tons of stuff. Aaron is doing work to
> split things out to make code easier to read and so that its easier
> to review changes. See:
>
> https://lkml.kernel.org/r/20220130213214.1042497-1-atom...@redhat.com
>
> I think this is a good patch example which could benefit from that work.
> So I'd much prefer to see that work go in first than this, so to see if
> we can make the below changes more compartamentalized.
>
> Curious, how much testing has been put into this series?
I tested the change up to (including) patch 4 to verify it doesn't
introduce regression when not using
CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC,
Then I tested with patch 5. I first tried with the 'hello world' test
module. After that I loaded several important modules and checked I
didn't get any regression, both with and without STRICT_MODULES_RWX and
I checked the consistency in /proc/vmallocinfo
/proc/modules /sys/class/modules/*
I also tested with a hacked module_alloc() to force branch trampolines.
Christophe
