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Date:   Sat, 25 Jul 2020 05:03:32 +0300
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     Ingo Molnar <mingo@kernel.org>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Andi Kleen <ak@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andy Lutomirski <luto@kernel.org>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Marco Elver <elver@google.com>,
        Babu Moger <Babu.Moger@amd.com>,
        Brian Gerst <brgerst@gmail.com>,
        Nayna Jain <nayna@linux.ibm.com>
Subject: Re: [PATCH v5 3/6] arch/x86: Implement text_alloc() and text_free()
Message-ID: <20200725020332.GA17052@linux.intel.com>
References: <20200724050553.1724168-1-jarkko.sakkinen@linux.intel.com>
 <20200724050553.1724168-4-jarkko.sakkinen@linux.intel.com>
 <20200724092258.GC517988@gmail.com>
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On Fri, Jul 24, 2020 at 11:22:58AM +0200, Ingo Molnar wrote:
> 
> * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> wrote:
> 
> > +void text_free(void *region)
> > +{
> > +	/*
> > +	 * This memory may be RO, and freeing RO memory in an interrupt is not
> > +	 * supported by vmalloc.
> > +	 */
> > +	lockdep_assert_irqs_enabled();
> > +
> > +	vfree(region);
> 
> Had to dig around a bit to find the source of this restriction. Might 
> make sense to clarify this comment to:
> 
> 	/*
> 	 * This memory may be read-only, and freeing VM_FLUSH_RESET_PERMS memory
> 	 * in an interrupt is not supported by vmalloc.
> 	 */

This definitely clarifies and is a better explanation. I updated the
commit accordingly. Thank you.

> 
> Thanks,
> 
> 	Ingo

/Jarkko