From nobody Sun Feb 8 02:34:51 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3B2CC23814A for ; Wed, 2 Apr 2025 09:46:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743587175; cv=none; b=LrZmv+ym8T4zofXRgmjgswwXx8w/8iziqvr5Qd4o+9qLhSIOM0GIEDqUcKutgCYRt3MIL0ZZs3AEi3aSEhdf/vjNmENqmI/dxvPxF3F1rE9W/DXLeR5p0SB5mJwWGGQaGbgNkCZlAjmbYf+PLt3BIxQUkIYWW/P3eneGXEY2iog= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743587175; c=relaxed/simple; bh=UM46Z3LywVA8SgF6vCR4JHx+WH4GLGG/jRvAXsdQuKI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hXDQCwQMORqJcwkyXUCeokhAqfw1LF45g4Vk784ObB6EKEdf8symQVB2h49Hm66jUX4NAga63/vQw51omrT7jgahSTpIt+DoTjs3Ghb3Add4R8H0OCsFg9XB910EDNgZ3C6tqbmtpi/IV0FKelZheApv+KHCrtWqHBiW2EQE4+Q= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kB7v57eZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kB7v57eZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 207D6C4CEE8; Wed, 2 Apr 2025 09:46:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743587175; bh=UM46Z3LywVA8SgF6vCR4JHx+WH4GLGG/jRvAXsdQuKI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kB7v57eZ5YAJXipGlLqcskI5To4WGavXLSdxv96UgnMcU78H3tEM3ydAAfwNhJq17 eTaoRKwA5V7PAli6MdHnXcLIAf8RAic6cnFc1FafsIhCc3Qoliy45sy0ETxmcgAyhB J0rJrhFmHIPInDk1IOt6sQcHfBhVL2IRma4m7KQ6GOL3nJLzHwE6RkBG2BcltHAtCv HorHOpnnl51htcdw5UeCKv0nh4O6Y4nt1dt3tGlurABUev9emJPqK89uQKRhIvZ6xE cDx+1oCFO1ide/j2SOt4isZioUSrQHh+RpoxLaQvo9EJBrlcIqsyZ7NPQ0KLMT6y9C UaHSjGYFvoUGg== From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: Andy Lutomirski , Rik van Riel , "H . Peter Anvin" , Peter Zijlstra , Linus Torvalds , Andrew Morton , Ingo Molnar Subject: [PATCH 6/7] x86/efi: Make efi_enter/leave_mm() use the use_/unuse_temporary_mm() machinery Date: Wed, 2 Apr 2025 11:45:39 +0200 Message-ID: <20250402094540.3586683-7-mingo@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20250402094540.3586683-1-mingo@kernel.org> References: <20250402094540.3586683-1-mingo@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Andy Lutomirski This should be considerably more robust. It's also necessary for optimized for_each_possible_lazymm_cpu() on x86 -- without this patch, EFI calls in lazy context would remove the lazy mm from mm_cpumask(). [ mingo: Merged it on top of x86/alternatives ] Signed-off-by: Andy Lutomirski Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Cc: Rik van Riel Cc: "H. Peter Anvin" Cc: Linus Torvalds Link: https://lore.kernel.org/r/20241119163035.877939834@infradead.org --- arch/x86/platform/efi/efi_64.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index ac57259a432b..a5d3496d32a5 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -434,15 +434,12 @@ void __init efi_dump_pagetable(void) */ static void efi_enter_mm(void) { - efi_prev_mm =3D current->active_mm; - current->active_mm =3D &efi_mm; - switch_mm(efi_prev_mm, &efi_mm, NULL); + efi_prev_mm =3D use_temporary_mm(&efi_mm); } =20 static void efi_leave_mm(void) { - current->active_mm =3D efi_prev_mm; - switch_mm(&efi_mm, efi_prev_mm, NULL); + unuse_temporary_mm(efi_prev_mm); } =20 void arch_efi_call_virt_setup(void) --=20 2.45.2