From: Federico Vaga <federico.vaga-vJEk5272eHo@public.gmane.org>
To: German Maglione <gmaglione-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Cc: initramfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH] dracut: dmsquash-live: overlay module can be built-in the kernel
Date: Thu, 5 May 2022 09:01:12 +0200 [thread overview]
Message-ID: <20220505070112.xnga2m4hu4e5a3jn@cwe-513-vol689.cern.ch> (raw)
In-Reply-To: <CAJh=p+7tGGaQNpwBfmKNp8+Zwu+vDV2u-xO2z-CHB44j6aQ-xQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
Crystal clear, thanks! I will submit a V2 patch using curly brackets
On Wed, May 04, 2022 at 12:03:26PM +0200, German Maglione wrote:
>On Tue, Apr 26, 2022 at 10:40 AM Federico Vaga <federico.vaga-vJEk5272eHo@public.gmane.org> wrote:
>>
>> On Fri, Apr 22, 2022 at 01:04:45PM +0200, German Maglione wrote:
>> >On Wed, Apr 20, 2022 at 9:17 AM Federico Vaga <federico.vaga-vJEk5272eHo@public.gmane.org> wrote:
>> >>
>> >> The dmsquash-live module assumes that `overlay` is always a module.
>> >> Therefore, when `overlay` is built-in the kernel, this module will fail
>> >> to detect the presence of such a feature.
>> >>
>> >> This patch adds a fallback mechanism to check also `/proc/filesystem`.
>> >> This is also what happens with the dracut NSF module when loading the
>> >> kernel module `rpc_pipefs`.
>> >>
>> >> Signed-off-by: Federico Vaga <federico.vaga-vJEk5272eHo@public.gmane.org>
>> >> ---
>> >> modules.d/90dmsquash-live/dmsquash-live-root.sh | 2 +-
>> >> 1 file changed, 1 insertion(+), 1 deletion(-)
>> >>
>> >> diff --git a/modules.d/90dmsquash-live/dmsquash-live-root.sh b/modules.d/90dmsquash-live/dmsquash-live-root.sh
>> >> index fd8a858a..b4a44e92 100755
>> >> --- a/modules.d/90dmsquash-live/dmsquash-live-root.sh
>> >> +++ b/modules.d/90dmsquash-live/dmsquash-live-root.sh
>> >> @@ -170,7 +170,7 @@ do_live_overlay() {
>> >> fi
>> >> fi
>> >> if [ -n "$overlayfs" ]; then
>> >> - if ! modprobe overlay; then
>> >> + if ! (modprobe overlay || strstr "$(cat /proc/filesystems)" overlay); then
>> >
>> >if ! { modprobe overlay || strstr "$(cat /proc/filesystems)" overlay; }; then
>> >
>> >I recently made the same mistake of using a subshell.
>>
>> For my understanding:
>>
>> Why do you think it's a mistake to use a subshell?
>>
>> Are you thinking about execution performance, or some locale variable
>> that do not get exported to the subshell?
>
>Well, maybe "mistake" was not the best word to use in this case,
>the subshell here it's simply unnecessary
>
>> Then, why curly brackets and not double square brackets?
>
>do you mean like:
>if ! [[ modprobe overlay; ]]; then
>this is a mistake, you cannot wrap commands in [[ ]] (or []), try this:
>
>[[ false ]] && echo "you should not see this"
>
>> I see the latter is far more used among modules; even if it is
>> enforcing a dependency on bash (or whatever supports `[[`)
>
>That the hooks be posix compliant (as you said [[ can be considered as
>a bashism)
>is explicitly required In the dracut docs, although it is true that
>there are some hooks
>that use [[, but mostly setup scripts.
>
>>
>> Thanks in advance for the clarifications :)
>>
>> >> if [ "$overlayfs" = required ]; then
>> >> die "OverlayFS is required but not available."
>> >> exit 1
>> >> --
>> >> 2.27.0
>> >>
>> >
>> >
>> >--
>> >German
>> >
>>
>
>
>--
>German
>
prev parent reply other threads:[~2022-05-05 7:01 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-20 7:15 [PATCH] dracut: dmsquash-live: overlay module can be built-in the kernel Federico Vaga
[not found] ` <20220420071523.1185188-1-federico.vaga-vJEk5272eHo@public.gmane.org>
2022-04-22 11:04 ` German Maglione
[not found] ` <CAJh=p+6s1q3yxVxTPePDOx1JyGKi+14RXqtzHirqYYtAihdqww-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2022-04-26 8:40 ` Federico Vaga
[not found] ` <20220426084005.7d5cso3ik2dcfosh-A6n7nn9GgJBD7ITmBszAl7ajPOKdvyMf@public.gmane.org>
2022-05-04 10:03 ` German Maglione
[not found] ` <CAJh=p+7tGGaQNpwBfmKNp8+Zwu+vDV2u-xO2z-CHB44j6aQ-xQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2022-05-05 7:01 ` Federico Vaga [this message]
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