Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1452385

Re: [PATCH 2/4] x86/platform/UV: Fix problem with bad UV4 EFI System Table causing panic

Show all headers | View raw

On Wed, 27 Jul 2016, Mike Travis wrote:

> Fix a problem that occurs if for some reason the UV4 EFI System Table
> is not available, the check inadvertantly can cause a panic.
> 
> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
> Reviewed-by: Nathan Zimmer <nzimmer@sgi.com>
> Tested-by: Frank Ramsay <framsay@sgi.com>
> Tested-by: John Estabrook <estabrook@sgi.com>
> Signed-off-by: Mike Travis <travis@sgi.com>
> ---
>  arch/x86/platform/uv/bios_uv.c |    7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> --- linux-3.12.orig/arch/x86/platform/uv/bios_uv.c
> +++ linux-3.12/arch/x86/platform/uv/bios_uv.c
> @@ -201,11 +201,12 @@ void uv_bios_init(void)
>  	}
>  
>  	if (uv_systab->revision >= UV_SYSTAB_VERSION_UV4) {
> +		int size = uv_systab->size;
> +
>  		iounmap(uv_systab);
> -		uv_systab = ioremap(efi.uv_systab, uv_systab->size);

I think the changelog is bogus. What's happening here is a classic use after
unmap, which you avoid by this change.

> +		uv_systab = ioremap(efi.uv_systab, size);

Hmm?

	tglx

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 2/4] x86/platform/UV: Fix problem with bad UV4 EFI System Table causing panic Mike Travis <travis@sgi.com> - 2016-07-27 19:50 +0200
  Re: [PATCH 2/4] x86/platform/UV: Fix problem with bad UV4 EFI System  Table causing panic Thomas Gleixner <tglx@linutronix.de> - 2016-07-29 13:20 +0200
    Re: [PATCH 2/4] x86/platform/UV: Fix problem with bad UV4 EFI System  Table causing panic Mike Travis <travis@sgi.com> - 2016-07-29 18:40 +0200

csiph-web