linux-kernel - Re: [PATCH]x86 efi: do not export efi runtime map in case old map

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20140530125900.GB16605@redhat.com>
Date:	Fri, 30 May 2014 08:59:00 -0400
From:	Vivek Goyal <vgoyal@...hat.com>
To:	Dave Young <dyoung@...hat.com>
Cc:	matt.fleming@...el.com, bp@...en8.de, linux-kernel@...r.kernel.org,
	linux-efi@...r.kernel.org
Subject: Re: [PATCH]x86 efi: do not export efi runtime map in case old map

On Fri, May 30, 2014 at 11:20:10AM +0800, Dave Young wrote:
> 
> For ioremapped efi memory aka old_map the virt addresses are not persistant
> across kexec reboot. kexec-tools will read the runtime maps from sysfs then
> pass them to 2nd kernel and assuming kexec efi boot is ok. This will cause
> kexec boot failure.
> 
> To address this issue do not export runtime maps in case efi old_map so
> userspace can use no efi boot instead.
> 
> Signed-off-by: Dave Young <dyoung@...hat.com>

Looks good to me.

Acked-by: Vivek Goyal <vgoyal@...hat.com>

Vivek

> ---
>  arch/x86/platform/efi/efi.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
> index 3781dd3..4d36932 100644
> --- a/arch/x86/platform/efi/efi.c
> +++ b/arch/x86/platform/efi/efi.c
> @@ -919,6 +919,9 @@ static void __init save_runtime_map(void)
>  	void *tmp, *p, *q = NULL;
>  	int count = 0;
>  
> +	if (efi_enabled(EFI_OLD_MEMMAP))
> +		return;
> +
>  	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
>  		md = p;
>  
> -- 
> 1.8.3.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/