[PATCH 1/4] powerpc/tm: Add commandline option to disable hardware transactional memory

[David Laight]

From: Michael Neuling
> Sent: 21 October 2017 02:00
> To: David Laight; 'Breno Leitao'; Michael Ellerman
> Cc: stewart at linux.vnet.ibm.com; linuxppc-dev at ozlabs.org; cyrilbur at gmail.com
> Subject: Re: [PATCH 1/4] powerpc/tm: Add commandline option to disable hardware transactional memory
> 
> On Fri, 2017-10-20 at 12:58 +0000, David Laight wrote:
> > > > This patch adds a simple commandline option so that HTM can be
> > > > disabled at boot time.
> >
> > ISTM that being able to disable it after boot would be more useful.
> > (ie in a startup script)
> 
> I agree bug unfortunately that's impossible.
> 
> If a process is already running in tm suspend, there is no way to stop it other
> than killing the process.  At that point you may as well kexec with a new
> cmdline option

Isn't that unlikely when the first rc scripts are being run?
Setting an early rc script is generally easier than adding a command line
parameter.

I don't know about ppc, but grub on x86 makes it painfully almost
impossible to have two boot entries that have different command line
options.

	David