From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752672AbcD2TqV (ORCPT ); Fri, 29 Apr 2016 15:46:21 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:34349 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752301AbcD2TqU (ORCPT ); Fri, 29 Apr 2016 15:46:20 -0400 Date: Fri, 29 Apr 2016 21:46:15 +0200 From: Ingo Molnar To: "Compostella, Jeremy" Cc: Matt Fleming , stefan.stanacar@intel.com, peterz@infradead.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, hpa@zytor.com, bp@alien8.de, ard.biesheuvel@linaro.org, linux-tip-commits@vger.kernel.org Subject: Re: [tip:efi/core] efibc: Add EFI Bootloader Control module Message-ID: <20160429194615.GA22691@gmail.com> References: <1461614832-17633-26-git-send-email-matt@codeblueprint.co.uk> <20160429095356.GA29957@gmail.com> <20160429103011.GE2839@codeblueprint.co.uk> <87lh3wejfi.fsf@jcompost-MOBL1.tl.intel.com> <20160429121635.GF2839@codeblueprint.co.uk> <87h9eked24.fsf@jcompost-MOBL1.tl.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87h9eked24.fsf@jcompost-MOBL1.tl.intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Compostella, Jeremy wrote: > -static void efibc_set_variable(const char *name, const char *value) > +static int efibc_set_variable(const char *name, const char *value) > { > int ret; > efi_guid_t guid = LINUX_EFI_LOADER_ENTRY_GUID; > - struct efivar_entry entry; > + struct efivar_entry *entry; > size_t size = (strlen(value) + 1) * sizeof(efi_char16_t); > > - if (size > sizeof(entry.var.Data)) > + if (size > sizeof(entry->var.Data)) { > pr_err("value is too large"); > + return -1; > + } > > - efibc_str_to_str16(name, entry.var.VariableName); > - efibc_str_to_str16(value, (efi_char16_t *)entry.var.Data); > - memcpy(&entry.var.VendorGuid, &guid, sizeof(guid)); > + entry = kmalloc(sizeof(*entry), GFP_KERNEL); > + if (!entry) { > + pr_err("failed to allocate efivar entry"); > + return -1; > + } > > - ret = efivar_entry_set(&entry, > + efibc_str_to_str16(name, entry->var.VariableName); > + efibc_str_to_str16(value, (efi_char16_t *)entry->var.Data); > + memcpy(&entry->var.VendorGuid, &guid, sizeof(guid)); > + > + ret = efivar_entry_set(entry, > EFI_VARIABLE_NON_VOLATILE > | EFI_VARIABLE_BOOTSERVICE_ACCESS > | EFI_VARIABLE_RUNTIME_ACCESS, > - size, entry.var.Data, NULL); > + size, entry->var.Data, NULL); > if (ret) > pr_err("failed to set %s EFI variable: 0x%x\n", > name, ret); > + > + kfree(entry); > + return ret; > } > > static int efibc_reboot_notifier_call(struct notifier_block *notifier, > unsigned long event, void *data) > { > const char *reason = "shutdown"; > + int ret; > > if (event == SYS_RESTART) > reason = "reboot"; > > - efibc_set_variable("LoaderEntryRebootReason", reason); > - > - if (!data) > - return NOTIFY_DONE; > + ret = efibc_set_variable("LoaderEntryRebootReason", reason); > + if (ret || !data) > + return NOTIFY_DONE; > > efibc_set_variable("LoaderEntryOneShot", (char *)data); Hm, can reboot notifiers do non-atomic allocations? Why is efivar_entry so huge? Thanks, Ingo