From: Julien Grall <julien@xen.org>
To: Luca Fancellu <luca.fancellu@arm.com>, xen-devel@lists.xenproject.org
Cc: bertrand.marquis@arm.com, wei.chen@arm.com,
Stefano Stabellini <sstabellini@kernel.org>,
Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
Subject: Re: [PATCH v4 3/4] xen/arm: Clarify how the domid is decided in create_domUs()
Date: Wed, 14 Apr 2021 12:17:18 +0100 [thread overview]
Message-ID: <658c2c00-1caa-38ce-9d10-751a8caf09da@xen.org> (raw)
In-Reply-To: <20210414091404.14215-4-luca.fancellu@arm.com>
On 14/04/2021 10:14, Luca Fancellu wrote:
> This patch adds a comment in create_domUs() right before
> domain_create() to explain the importance of the pre-increment
> operator on the variable max_init_domid, to ensure that the
> domid 0 is allocated only during start_xen() function by the
> create_dom0() and not on any other possible code path to the
> domain_create() function.
>
> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
> ---
> Changes in v4:
> - Change to the commit title
> Changes in v3:
> - removed check introduced in v2.
> ---
> xen/arch/arm/domain_build.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
> index 359957dc1b..b1d7b9849f 100644
> --- a/xen/arch/arm/domain_build.c
> +++ b/xen/arch/arm/domain_build.c
> @@ -2508,6 +2508,11 @@ void __init create_domUs(void)
> GUEST_VPL011_SPI - 32 + 1);
> }
>
> + /*
> + * The variable max_init_domid is initialized with zero, so here it's
> + * very important to use the pre-increment operator to call
> + * domain_create() with a domid > 0. (domid == 0 is reserved for Dom0)
> + */
> d = domain_create(++max_init_domid, &d_cfg, false);
> if ( IS_ERR(d) )
> panic("Error creating domain %s\n", dt_node_name(node));
>
--
Julien Grall
next prev parent reply other threads:[~2021-04-14 11:17 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-14 9:14 [PATCH v4 0/4] xen/arm: Prevent Dom0 to be loaded when using dom0less Luca Fancellu
2021-04-14 9:14 ` [PATCH v4 1/4] xen/arm: Move dom0 creation in domain_build.c Luca Fancellu
2021-04-14 10:14 ` Bertrand Marquis
2021-04-14 9:14 ` [PATCH v4 2/4] xen/arm: Handle cases when hardware_domain is NULL Luca Fancellu
2021-04-14 10:14 ` Bertrand Marquis
2021-04-14 11:16 ` Julien Grall
2021-04-14 11:29 ` Luca Fancellu
2021-04-14 13:45 ` Julien Grall
2021-04-14 13:47 ` Luca Fancellu
2021-04-14 20:35 ` Stefano Stabellini
2021-04-15 17:17 ` Julien Grall
2021-04-14 9:14 ` [PATCH v4 3/4] xen/arm: Clarify how the domid is decided in create_domUs() Luca Fancellu
2021-04-14 10:14 ` Bertrand Marquis
2021-04-14 11:17 ` Julien Grall [this message]
2021-04-14 9:14 ` [PATCH v4 4/4] xen/arm: Prevent Dom0 to be loaded when using dom0less Luca Fancellu
2021-04-14 10:14 ` Bertrand Marquis
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