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	Thu, 13 Mar 2025 20:44:00 +0000
Date: Thu, 13 Mar 2025 20:44:00 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Dev Jain <dev.jain@arm.com>
Cc: jroedel@suse.de, akpm@linux-foundation.org, ryan.roberts@arm.com,
	david@redhat.com, hch@lst.de, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] mm: Update mask post pxd_clear_bad()
Message-ID: <Z9NDkFzSj-vnvGOy@casper.infradead.org>
References: <20250313181414.78512-1-dev.jain@arm.com>
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In-Reply-To: <20250313181414.78512-1-dev.jain@arm.com>

On Thu, Mar 13, 2025 at 11:44:14PM +0530, Dev Jain wrote:
> Since pxd_clear_bad() is an operation changing the state of the page tables,
> we should call arch_sync_kernel_mappings() post this.

Could you explain why?  What effect does not calling
arch_sync_kernel_mappings() have in this case?