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Date:   Tue, 11 Apr 2023 23:35:07 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Stefan Roesch <shr@devkernel.io>
Cc:     kernel-team@fb.com, linux-mm@kvack.org, riel@surriel.com,
        mhocko@suse.com, david@redhat.com, linux-kselftest@vger.kernel.org,
        linux-doc@vger.kernel.org, akpm@linux-foundation.org,
        hannes@cmpxchg.org, Bagas Sanjaya <bagasdotme@gmail.com>
Subject: Re: [PATCH v5 1/3] mm: add new api to enable ksm per process
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References: <20230406165339.1017597-1-shr@devkernel.io>
 <20230406165339.1017597-2-shr@devkernel.io>
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On Thu, Apr 06, 2023 at 09:53:37AM -0700, Stefan Roesch wrote:
> +	case PR_SET_MEMORY_MERGE:
> +		if (mmap_write_lock_killable(me->mm))
> +			return -EINTR;
> +
> +		if (arg2) {
> +			int err = ksm_add_mm(me->mm);
> +			if (err)
> +				return err;

You'll return to userspace with the mutex held, no?