Le 09/12/2022 à 14:38, Xander a écrit : > > The pgprot parameter got removed because, according to the commit log, > for no other apparent reason than it being called with 'PAGE_KERNEL' as > an argument in the whole kernel. Therefore it got removed. > This removed the ability to allocate virtual memory with executing rights. > My use case comes from ioremap(). > I think this is useful for others too. > > I don't see why this pgprot parameter got removed but this is the > alternative to reverting it to the older 5.7 function. Please avoid top-posting, and use only plain text. I think you don't answer to Mark's question. You are adding a new function that no driver uses apparently. If you are working on some piece of code that needs this new fonction, you can send this patch as part of a patch series including that code. By the way, when you need executable memory, the fonction to use is module_alloc(), that's the only function that garanties real executable memory on all platforms. For instance, on some powerpc, setting the X bit is not enough to get executable memory in vmalloc space. Christophe > > On Fri, 9 Dec 2022 at 14:17, Mark Rutland <mark.rutland@xxxxxxx > <mailto:mark.rutland@xxxxxxx>> wrote: > > On Fri, Dec 09, 2022 at 02:10:52PM +0100, Xander Moerkerken wrote: > > From: Xander Moerkerken <xander.moerkerken@xxxxxxxxx > <mailto:xander.moerkerken@xxxxxxxxx>> > > > > Since release 5.8-rc1 the pgprot got removed from __vmalloc > > because the only usage was PAGE_KERNEL as argument. > > However, this removes the ability to input other arguments > > such as 'PAGE_KERNEL_EXEC', which can be used to allocate > > memory in which you can execute. For this reason a new > > function is introduced called '__vmalloc_exec'. > > > > Signed-off-by: Xander Moerkerken <xander.moerkerken@xxxxxxxxx > <mailto:xander.moerkerken@xxxxxxxxx>> > > What is this going to be used for? There's no user from this patch > alone, as a > module or otherwise. > > Mark. > > > --- > > include/linux/vmalloc.h | 1 + > > mm/vmalloc.c | 8 ++++++++ > > 2 files changed, 9 insertions(+) > > > > diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h > > index 096d48aa3437..10c46513b6b2 100644 > > --- a/include/linux/vmalloc.h > > +++ b/include/linux/vmalloc.h > > @@ -147,6 +147,7 @@ extern void *vzalloc_node(unsigned long size, > int node) __alloc_size(1); > > extern void *vmalloc_32(unsigned long size) __alloc_size(1); > > extern void *vmalloc_32_user(unsigned long size) __alloc_size(1); > > extern void *__vmalloc(unsigned long size, gfp_t gfp_mask) > __alloc_size(1); > > +extern void *__vmalloc_exec(unsigned long size, gfp_t gfp_mask) > __alloc_size(1); > > extern void *__vmalloc_node_range(unsigned long size, unsigned > long align, > > unsigned long start, unsigned long end, > gfp_t gfp_mask, > > pgprot_t prot, unsigned long vm_flags, int > node, > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > > index ccaa461998f3..8fd01ed7082b 100644 > > --- a/mm/vmalloc.c > > +++ b/mm/vmalloc.c > > @@ -3294,6 +3294,14 @@ void *__vmalloc(unsigned long size, gfp_t > gfp_mask) > > } > > EXPORT_SYMBOL(__vmalloc); > > > > + > > +void *__vmalloc_exec(unsigned long size, gfp_t gfp_mask) > > +{ > > + return __vmalloc_node_prot(size, 1, gfp_mask, PAGE_KERNEL_EXEC, > > + NUMA_NO_NODE, > __builtin_return_address(0)); > > +} > > +EXPORT_SYMBOL(__vmalloc_exec); > > + > > /** > > * vmalloc - allocate virtually contiguous memory > > * @size: allocation size > > -- > > 2.37.2 > > >
