linux-kernel - Re: Infinite loop on boot in free_early_partial due to start==end on tip/master

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: <20100319182807.GA14985@phenom.dumpdata.com>
Date:	Fri, 19 Mar 2010 14:28:07 -0400
From:	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
To:	Ian Campbell <Ian.Campbell@...rix.com>
Cc:	Yinghai Lu <yinghai@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...e.hu>,
	linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: Infinite loop on boot in free_early_partial due to start==end
	on tip/master

> Subject: x86: do not free zero sized per cpu areas
> 
> This avoids an infinite loop in free_early_partial().

The patch fixed PV guests booting on Xen. I've added my
Tested-by .. Please merge it in the release.

Thanks!
> 
> Add a warning to free_early_partial to catch future problems.
> 
> Signed-off-by: Ian Campbell <ian.campbell@...rix.com>

Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
> 
> 
> 
> --
> 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/
> 
> diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
> index ef6370b..89a3205 100644
> --- a/arch/x86/kernel/setup_percpu.c
> +++ b/arch/x86/kernel/setup_percpu.c
> @@ -140,7 +140,8 @@ static void __init pcpu_fc_free(void *ptr, size_t size)
>  #ifdef CONFIG_NO_BOOTMEM
>  	u64 start = __pa(ptr);
>  	u64 end = start + size;
> -	free_early_partial(start, end);
> +	if (start < end)
> +		free_early_partial(start, end);
>  #else
>  	free_bootmem(__pa(ptr), size);
>  #endif
> diff --git a/kernel/early_res.c b/kernel/early_res.c
> index 3cb2c66..fbde443 100644
> --- a/kernel/early_res.c
> +++ b/kernel/early_res.c
> @@ -333,6 +333,8 @@ void __init free_early_partial(u64 start, u64 end)
>  	struct early_res *r;
>  	int i;
>  
> +	WARN_ON(start>=end);
> +
>  try_next:
>  	i = find_overlapped_early(start, end);
>  	if (i >= max_early_res)
--
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/