[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <Y3t+BipyGPUV3q8F@zn.tnic>
Date: Mon, 21 Nov 2022 14:32:54 +0100
From: Borislav Petkov <bp@...en8.de>
To: Michael Kelley <mikelley@...rosoft.com>
Cc: hpa@...or.com, kys@...rosoft.com, haiyangz@...rosoft.com,
wei.liu@...nel.org, decui@...rosoft.com, luto@...nel.org,
peterz@...radead.org, davem@...emloft.net, edumazet@...gle.com,
kuba@...nel.org, pabeni@...hat.com, lpieralisi@...nel.org,
robh@...nel.org, kw@...ux.com, bhelgaas@...gle.com, arnd@...db.de,
hch@...radead.org, m.szyprowski@...sung.com, robin.murphy@....com,
thomas.lendacky@....com, brijesh.singh@....com, tglx@...utronix.de,
mingo@...hat.com, dave.hansen@...ux.intel.com,
Tianyu.Lan@...rosoft.com, kirill.shutemov@...ux.intel.com,
sathyanarayanan.kuppuswamy@...ux.intel.com, ak@...ux.intel.com,
isaku.yamahata@...el.com, dan.j.williams@...el.com,
jane.chu@...cle.com, seanjc@...gle.com, tony.luck@...el.com,
x86@...nel.org, linux-kernel@...r.kernel.org,
linux-hyperv@...r.kernel.org, netdev@...r.kernel.org,
linux-pci@...r.kernel.org, linux-arch@...r.kernel.org,
iommu@...ts.linux.dev
Subject: Re: [Patch v3 01/14] x86/ioremap: Fix page aligned size calculation
in __ioremap_caller()
On Wed, Nov 16, 2022 at 10:41:24AM -0800, Michael Kelley wrote:
> Current code re-calculates the size after aligning the starting and
> ending physical addresses on a page boundary. But the re-calculation
> also embeds the masking of high order bits that exceed the size of
> the physical address space (via PHYSICAL_PAGE_MASK). If the masking
> removes any high order bits, the size calculation results in a huge
> value that is likely to immediately fail.
>
> Fix this by re-calculating the page-aligned size first. Then mask any
> high order bits using PHYSICAL_PAGE_MASK.
>
> Signed-off-by: Michael Kelley <mikelley@...rosoft.com>
> ---
> arch/x86/mm/ioremap.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
> index 78c5bc6..6453fba 100644
> --- a/arch/x86/mm/ioremap.c
> +++ b/arch/x86/mm/ioremap.c
> @@ -217,9 +217,15 @@ static void __ioremap_check_mem(resource_size_t addr, unsigned long size,
> * Mappings have to be page-aligned
> */
> offset = phys_addr & ~PAGE_MASK;
> - phys_addr &= PHYSICAL_PAGE_MASK;
> + phys_addr &= PAGE_MASK;
> size = PAGE_ALIGN(last_addr+1) - phys_addr;
>
> + /*
> + * Mask out any bits not part of the actual physical
> + * address, like memory encryption bits.
> + */
> + phys_addr &= PHYSICAL_PAGE_MASK;
> +
> retval = memtype_reserve(phys_addr, (u64)phys_addr + size,
> pcm, &new_pcm);
> if (retval) {
> --
This looks like a fix to me that needs to go to independently to stable.
And it would need a Fixes tag.
/me does some git archeology...
I guess this one:
ffa71f33a820 ("x86, ioremap: Fix incorrect physical address handling in PAE mode")
should be old enough so that it goes to all relevant stable kernels...
Hmm?
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
Powered by blists - more mailing lists