[PATCH 2/8] efi/x86: Use non-blocking SetVariable() for efi_delete_dummy_variable()

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
To: linux-efi@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>
Cc: Sai Praneeth <sai.praneeth.prakhya@intel.com>,
	Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	linux-kernel@vger.kernel.org
Subject: [PATCH 2/8] efi/x86: Use non-blocking SetVariable() for efi_delete_dummy_variable()
Date: Wed, 11 Jul 2018 11:40:34 +0200	[thread overview]
Message-ID: <20180711094040.12506-3-ard.biesheuvel@linaro.org> (raw)
In-Reply-To: <20180711094040.12506-1-ard.biesheuvel@linaro.org>

From: Sai Praneeth <sai.praneeth.prakhya@intel.com>

Presently, efi_delete_dummy_variable() uses set_variable() which might
block and hence kernel prints stack trace with a warning "bad:
scheduling from the idle thread!". So, make efi_delete_dummy_variable()
use set_variable_nonblocking(), which, as the name suggests doesn't
block.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 arch/x86/platform/efi/quirks.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index 36c1f8b9f7e0..6af39dc40325 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -105,12 +105,11 @@ early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 */
 void efi_delete_dummy_variable(void)
 {
-	efi.set_variable((efi_char16_t *)efi_dummy_name,
-			 &EFI_DUMMY_GUID,
-			 EFI_VARIABLE_NON_VOLATILE |
-			 EFI_VARIABLE_BOOTSERVICE_ACCESS |
-			 EFI_VARIABLE_RUNTIME_ACCESS,
-			 0, NULL);
+	efi.set_variable_nonblocking((efi_char16_t *)efi_dummy_name,
+				     &EFI_DUMMY_GUID,
+				     EFI_VARIABLE_NON_VOLATILE |
+				     EFI_VARIABLE_BOOTSERVICE_ACCESS |
+				     EFI_VARIABLE_RUNTIME_ACCESS, 0, NULL);
 }
 
 /*
-- 
2.17.1

