From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B8D8F3939DD; Mon, 16 Mar 2026 12:12:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773663181; cv=none; b=UIgYJyvT8+W1VDI06K0kCbkfkbver7JQKpgYKvVQP0+UQ/gPpJkeQPytUVOuyAyrRIxFnIK1Lvd9/JFCYBRODn5f+e5zL1Gm2rbUAdaH9SXPCf6fxkTb25vlx4+qrlyMCtnZ5HawtTeIEoV6vLIU+xYwDAA9VByKIeppsw3r6Sg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773663181; c=relaxed/simple; bh=MVIADVbueLx3yQEJ2iYnj2s1XkLRnQtQerVrnAstgKk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NlAS7HCwM9edbVDK9LRaDR+ajUmHiS+6AxALu2zTrR81GUp0K9L3rxPO3RMyiqYO65qy4Bgtf6LgSVPQeAJGpX7x3VWI8DDpIw2F62inpnF7pPGjUUP1XB7e/3Xg+ENaSU/euaV/hqyqDbn2/g6rHxOXi9RmP4iT6PkRYlD/Kp8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=JnrfaQ1q; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="JnrfaQ1q" Received: from CPC-namja-026ON.redmond.corp.microsoft.com (unknown [4.213.232.19]) by linux.microsoft.com (Postfix) with ESMTPSA id C980B20B7129; Mon, 16 Mar 2026 05:12:52 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C980B20B7129 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1773663179; bh=6df6NmlHbYEwsjePCZxMwR+//HiqFND2iuF0yusrO7A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JnrfaQ1qzJtMxSWlOSqo+uWUtX+v3P2ZCsXLOhdyHnOiD5Mf/g2gbHMdnHNx1+B0e HG2BK6FeWTAuENeXTbTg7QebepK3AW7xpc2WLe6mfQa3LB3dskvBj/x9U7s0qec5Nj uex5YeK0kEHqZinvkTyE9P6h/eVsH96Ez3dITCIY= From: Naman Jain To: "K . Y . Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Arnd Bergmann , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti Cc: Marc Zyngier , Timothy Hayes , Lorenzo Pieralisi , mrigendrachaubey , Naman Jain , ssengar@linux.microsoft.com, Michael Kelley , linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-riscv@lists.infradead.org Subject: [PATCH 01/11] arch: arm64: Export arch_smp_send_reschedule for mshv_vtl module Date: Mon, 16 Mar 2026 12:12:31 +0000 Message-ID: <20260316121241.910764-2-namjain@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260316121241.910764-1-namjain@linux.microsoft.com> References: <20260316121241.910764-1-namjain@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit mshv_vtl_main.c calls smp_send_reschedule() which expands to arch_smp_send_reschedule(). When CONFIG_MSHV_VTL=m, the module cannot access this symbol since it is not exported on arm64. smp_send_reschedule() is used in mshv_vtl_cancel() to interrupt a vCPU thread running on another CPU. When a vCPU is looping in mshv_vtl_ioctl_return_to_lower_vtl(), it checks a per-CPU cancel flag before each VTL0 entry. Setting cancel=1 alone is not enough if the target CPU thread is sleeping - the IPI from smp_send_reschedule() kicks the remote CPU out of idle/sleep so it re-checks the cancel flag and exits the loop promptly. Other architectures (riscv, loongarch, powerpc) already export this symbol. Add the same EXPORT_SYMBOL_GPL for arm64. This is required for adding arm64 support in MSHV_VTL. Signed-off-by: Naman Jain --- arch/arm64/kernel/smp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 1aa324104afb..26b1a4456ceb 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -1152,6 +1152,7 @@ void arch_smp_send_reschedule(int cpu) { smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE); } +EXPORT_SYMBOL_GPL(arch_smp_send_reschedule); #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL void arch_send_wakeup_ipi(unsigned int cpu) -- 2.43.0