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2022-08-02Merge tag 'flexible-array-transformations-UAPI-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linuxLinus Torvalds1-1/+1
Pull uapi flexible array update from Gustavo Silva: "A treewide patch that replaces zero-length arrays with flexible-array members in UAPI. This has been baking in linux-next for 5 weeks now. '-fstrict-flex-arrays=3' is coming and we need to land these changes to prevent issues like these in the short future: fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0, but the source string has length 2 (including NUL byte) [-Wfortify-source] strcpy(de3->name, "."); ^ Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If this breaks anything, we can use a union with a new member name" Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836 * tag 'flexible-array-transformations-UAPI-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: treewide: uapi: Replace zero-length arrays with flexible-array members
2022-07-11x86/setup: Use rng seeds from setup_dataJason A. Donenfeld1-3/+3
Currently, the only way x86 can get an early boot RNG seed is via EFI, which is generally always used now for physical machines, but is very rarely used in VMs, especially VMs that are optimized for starting "instantaneously", such as Firecracker's MicroVM. For tiny fast booting VMs, EFI is not something you generally need or want. Rather, the image loader or firmware should be able to pass a single random seed, exactly as device tree platforms do with the "rng-seed" property. Additionally, this is something that bootloaders can append, with their own seed file management, which is something every other major OS ecosystem has that Linux does not (yet). Add SETUP_RNG_SEED, similar to the other eight setup_data entries that are parsed at boot. It also takes care to zero out the seed immediately after using, in order to retain forward secrecy. This all takes about 7 trivial lines of code. Then, on kexec_file_load(), a new fresh seed is generated and passed to the next kernel, just as is done on device tree architectures when using kexec. And, importantly, I've tested that QEMU is able to properly pass SETUP_RNG_SEED as well, making this work for every step of the way. This code too is pretty straight forward. Together these measures ensure that VMs and nested kexec()'d kernels always receive a proper boot time RNG seed at the earliest possible stage from their parents: - Host [already has strongly initialized RNG] - QEMU [passes fresh seed in SETUP_RNG_SEED field] - Linux [uses parent's seed and gathers entropy of its own] - kexec [passes this in SETUP_RNG_SEED field] - Linux [uses parent's seed and gathers entropy of its own] - kexec [passes this in SETUP_RNG_SEED field] - Linux [uses parent's seed and gathers entropy of its own] - kexec [passes this in SETUP_RNG_SEED field] - ... I've verified in several scenarios that this works quite well from a host kernel to QEMU and down inwards, mixing and matching loaders, with every layer providing a seed to the next. [ bp: Massage commit message. ] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com> Link: https://lore.kernel.org/r/20220630113300.1892799-1-Jason@zx2c4.com
2022-07-11Merge tag 'v5.19-rc6' into tip:x86/kdumpBorislav Petkov1-1/+1
Merge rc6 to pick up dependent changes to the bootparam UAPI header. Signed-off-by: Borislav Petkov <bp@suse.de>
2022-07-10x86/boot: Fix the setup data types max limitBorislav Petkov1-1/+1
Commit in Fixes forgot to change the SETUP_TYPE_MAX definition which contains the highest valid setup data type. Correct that. Fixes: 5ea98e01ab52 ("x86/boot: Add Confidential Computing type to setup_data") Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/ddba81dd-cc92-699c-5274-785396a17fb5@zytor.com
2022-07-01x86/kexec: Carry forward IMA measurement log on kexecJonathan McDowell1-0/+9
On kexec file load, the Integrity Measurement Architecture (IMA) subsystem may verify the IMA signature of the kernel and initramfs, and measure it. The command line parameters passed to the kernel in the kexec call may also be measured by IMA. A remote attestation service can verify a TPM quote based on the TPM event log, the IMA measurement list and the TPM PCR data. This can be achieved only if the IMA measurement log is carried over from the current kernel to the next kernel across the kexec call. PowerPC and ARM64 both achieve this using device tree with a "linux,ima-kexec-buffer" node. x86 platforms generally don't make use of device tree, so use the setup_data mechanism to pass the IMA buffer to the new kernel. Signed-off-by: Jonathan McDowell <noodles@fb.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> # IMA function definitions Link: https://lore.kernel.org/r/YmKyvlF3my1yWTvK@noodles-fedora-PC23Y6EG
2022-06-28treewide: uapi: Replace zero-length arrays with flexible-array membersGustavo A. R. Silva1-1/+1
There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. This code was transformed with the help of Coccinelle: (linux-5.19-rc2$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch) @@ identifier S, member, array; type T1, T2; @@ struct S { ... T1 member; T2 array[ - 0 ]; }; -fstrict-flex-arrays=3 is coming and we need to land these changes to prevent issues like these in the short future: ../fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0, but the source string has length 2 (including NUL byte) [-Wfortify-source] strcpy(de3->name, "."); ^ Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If this breaks anything, we can use a union with a new member name. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/78 Build-tested-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/lkml/62b675ec.wKX6AOZ6cbE71vtF%25lkp@intel.com/ Acked-by: Dan Williams <dan.j.williams@intel.com> # For ndctl.h Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2022-04-07x86/boot: Add a pointer to Confidential Computing blob in bootparamsMichael Roth1-1/+2
The previously defined Confidential Computing blob is provided to the kernel via a setup_data structure or EFI config table entry. Currently, these are both checked for by boot/compressed kernel to access the CPUID table address within it for use with SEV-SNP CPUID enforcement. To also enable that enforcement for the run-time kernel, similar access to the CPUID table is needed early on while it's still using the identity-mapped page table set up by boot/compressed, where global pointers need to be accessed via fixup_pointer(). This isn't much of an issue for accessing setup_data, and the EFI config table helper code currently used in boot/compressed *could* be used in this case as well since they both rely on identity-mapping. However, it has some reliance on EFI helpers/string constants that would need to be accessed via fixup_pointer(), and fixing it up while making it shareable between boot/compressed and run-time kernel is fragile and introduces a good bit of ugliness. Instead, add a boot_params->cc_blob_address pointer that the boot/compressed kernel can initialize so that the run-time kernel can access the CC blob from there instead of re-scanning the EFI config table. Also document these in Documentation/x86/zero-page.rst. While there, add missing documentation for the acpi_rsdp_addr field, which serves a similar purpose in providing the run-time kernel a pointer to the ACPI RSDP table so that it does not need to [re-]scan the EFI configuration table. [ bp: Fix typos, massage commit message. ] Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20220307213356.2797205-34-brijesh.singh@amd.com
2022-04-07x86/boot: Add Confidential Computing type to setup_dataBrijesh Singh1-0/+1
While launching encrypted guests, the hypervisor may need to provide some additional information during the guest boot. When booting under an EFI-based BIOS, the EFI configuration table contains an entry for the confidential computing blob that contains the required information. To support booting encrypted guests on non-EFI VMs, the hypervisor needs to pass this additional information to the guest kernel using a different method. For this purpose, introduce SETUP_CC_BLOB type in setup_data to hold the physical address of the confidential computing blob location. The boot loader or hypervisor may choose to use this method instead of an EFI configuration table. The CC blob location scanning should give preference to a setup_data blob over an EFI configuration table. In AMD SEV-SNP, the CC blob contains the address of the secrets and CPUID pages. The secrets page includes information such as a VM to PSP communication key and the CPUID page contains PSP-filtered CPUID values. Define the AMD SEV confidential computing blob structure. While at it, define the EFI GUID for the confidential computing blob. [ bp: Massage commit message, mark struct __packed. ] Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20220307213356.2797205-30-brijesh.singh@amd.com
2021-03-18x86: Fix various typos in commentsIngo Molnar1-2/+2
Fix ~144 single-word typos in arch/x86/ code comments. Doing this in a single commit should reduce the churn. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-kernel@vger.kernel.org
2020-07-26x86: bootparam.h: Delete duplicated wordRandy Dunlap1-1/+1
Delete the repeated word "for". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200726004124.20618-2-rdunlap@infradead.org
2019-11-26Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-9/+16
Pull x86 platform updates from Ingo Molnar: "UV platform updates (with a 'hubless' variant) and Jailhouse updates for better UART support" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/jailhouse: Only enable platform UARTs if available x86/jailhouse: Improve setup data version comparison x86/platform/uv: Account for UV Hubless in is_uvX_hub Ops x86/platform/uv: Check EFI Boot to set reboot type x86/platform/uv: Decode UVsystab Info x86/platform/uv: Add UV Hubbed/Hubless Proc FS Files x86/platform/uv: Setup UV functions for Hubless UV Systems x86/platform/uv: Add return code to UV BIOS Init function x86/platform/uv: Return UV Hubless System Type x86/platform/uv: Save OEM_ID from ACPI MADT probe
2019-11-12x86/boot: Introduce setup_indirectDaniel Kiper1-3/+13
The setup_data is a bit awkward to use for extremely large data objects, both because the setup_data header has to be adjacent to the data object and because it has a 32-bit length field. However, it is important that intermediate stages of the boot process have a way to identify which chunks of memory are occupied by kernel data. Thus introduce an uniform way to specify such indirect data as setup_indirect struct and SETUP_INDIRECT type. And finally bump setup_header version in arch/x86/boot/header.S. Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ross Philipson <ross.philipson@oracle.com> Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: ard.biesheuvel@linaro.org Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: dave.hansen@linux.intel.com Cc: eric.snowberg@oracle.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Juergen Gross <jgross@suse.com> Cc: kanth.ghatraju@oracle.com Cc: linux-doc@vger.kernel.org Cc: linux-efi <linux-efi@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: rdunlap@infradead.org Cc: ross.philipson@oracle.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20191112134640.16035-4-daniel.kiper@oracle.com
2019-11-12x86/boot: Introduce kernel_info.setup_type_maxDaniel Kiper1-0/+3
This field contains maximal allowed type for setup_data. Do not bump setup_header version in arch/x86/boot/header.S because it will be followed by additional changes coming into the Linux/x86 boot protocol. Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Ross Philipson <ross.philipson@oracle.com> Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: ard.biesheuvel@linaro.org Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: dave.hansen@linux.intel.com Cc: eric.snowberg@oracle.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Juergen Gross <jgross@suse.com> Cc: kanth.ghatraju@oracle.com Cc: linux-doc@vger.kernel.org Cc: linux-efi <linux-efi@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: rdunlap@infradead.org Cc: ross.philipson@oracle.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20191112134640.16035-3-daniel.kiper@oracle.com
2019-11-12x86/boot: Introduce kernel_infoDaniel Kiper1-0/+1
The relationships between the headers are analogous to the various data sections: setup_header = .data boot_params/setup_data = .bss What is missing from the above list? That's right: kernel_info = .rodata We have been (ab)using .data for things that could go into .rodata or .bss for a long time, for lack of alternatives and -- especially early on -- inertia. Also, the BIOS stub is responsible for creating boot_params, so it isn't available to a BIOS-based loader (setup_data is, though). setup_header is permanently limited to 144 bytes due to the reach of the 2-byte jump field, which doubles as a length field for the structure, combined with the size of the "hole" in struct boot_params that a protected-mode loader or the BIOS stub has to copy it into. It is currently 119 bytes long, which leaves us with 25 very precious bytes. This isn't something that can be fixed without revising the boot protocol entirely, breaking backwards compatibility. boot_params proper is limited to 4096 bytes, but can be arbitrarily extended by adding setup_data entries. It cannot be used to communicate properties of the kernel image, because it is .bss and has no image-provided content. kernel_info solves this by providing an extensible place for information about the kernel image. It is readonly, because the kernel cannot rely on a bootloader copying its contents anywhere, but that is OK; if it becomes necessary it can still contain data items that an enabled bootloader would be expected to copy into a setup_data chunk. Do not bump setup_header version in arch/x86/boot/header.S because it will be followed by additional changes coming into the Linux/x86 boot protocol. Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Ross Philipson <ross.philipson@oracle.com> Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: ard.biesheuvel@linaro.org Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: dave.hansen@linux.intel.com Cc: eric.snowberg@oracle.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Juergen Gross <jgross@suse.com> Cc: kanth.ghatraju@oracle.com Cc: linux-doc@vger.kernel.org Cc: linux-efi <linux-efi@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: rdunlap@infradead.org Cc: ross.philipson@oracle.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20191112134640.16035-2-daniel.kiper@oracle.com
2019-10-10x86/jailhouse: Only enable platform UARTs if availableRalf Ramsauer1-0/+3
ACPI tables aren't available if Linux runs as guest of the hypervisor Jailhouse. This makes the 8250 driver probe for all platform UARTs as it assumes that all UARTs are present in case of !ACPI. Jailhouse will stop execution of Linux guest due to port access violation. So far, these access violations were solved by tuning the 8250.nr_uarts cmdline parameter, but this has limitations: Only consecutive platform UARTs can be mapped to Linux, and only in the sequence 0x3f8, 0x2f8, 0x3e8, 0x2e8. Beginning from setup_data version 2, Jailhouse will place information of available platform UARTs in setup_data. This allows for selective activation of platform UARTs. Query setup_data version and only activate available UARTS. This patch comes with backward compatibility, and will still support older setup_data versions. In case of older setup_data versions, Linux falls back to the old behaviour. Signed-off-by: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Cc: Baoquan He <bhe@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: jailhouse-dev@googlegroups.com Cc: Juergen Gross <jgross@suse.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191010102102.421035-3-ralf.ramsauer@oth-regensburg.de
2019-10-10x86/jailhouse: Improve setup data version comparisonRalf Ramsauer1-9/+13
Soon, setup_data will contain information on passed-through platform UARTs. This requires some preparational work for the sanity check of the header and the check of the version. Use the following strategy: 1. Ensure that the header declares at least enough space for the version and the compatible_version as it must hold that fields for any version. The location and semantics of header+version fields will never change. 2. Copy over data -- as much as as possible. The length is either limited by the header length or the length of setup_data. 3. Things are now in place -- sanity check if the header length complies the actual version. For future versions of the setup_data, only step 3 requires alignment. Signed-off-by: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Cc: Baoquan He <bhe@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: jailhouse-dev@googlegroups.com Cc: Juergen Gross <jgross@suse.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191010102102.421035-2-ralf.ramsauer@oth-regensburg.de
2019-06-28x86/boot: Add xloadflags bits to check for 5-level paging supportBaoquan He1-0/+2
The current kernel supports 5-level paging mode, and supports dynamically choosing the paging mode during bootup depending on the kernel image, hardware and kernel parameter settings. This flexibility brings several issues to kexec/kdump: 1) Dynamic switching between paging modes requires support in the target kernel. This means kexec from a 5-level paging kernel into a kernel which does not support mode switching is not possible. So the loader needs to be able to analyze the supported paging modes of the kexec target kernel. 2) If running on a 5-level paging kernel and the kexec target kernel is a 4-level paging kernel, the target immage cannot be loaded above the 64TB address space limit. But the kexec loader searches for a load area from top to bottom which would eventually put the target kernel above 64TB when the machine has large enough RAM size. So the loader needs to be able to analyze the paging mode of the target kernel to load it at a suitable spot in the address space. Solution: Add two bits XLF_5LEVEL and XLF_5LEVEL_ENABLED: - Bit XLF_5LEVEL indicates whether 5-level paging mode switching support is available. (Issue #1) - Bit XLF_5LEVEL_ENABLED indicates whether the kernel was compiled with full 5-level paging support (CONFIG_X86_5LEVEL=y). (Issue #2) The loader will use these bits to verify whether the target kernel is suitable to be kexec'ed to from a 5-level paging kernel and to determine the constraints of the target kernel load address. The flags will be used by the kernel kexec subsystem and the userspace kexec tools. [ tglx: Massaged changelog ] Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: dyoung@redhat.com Link: https://lkml.kernel.org/r/20190524073810.24298-2-bhe@redhat.com
2018-11-20x86/acpi, x86/boot: Take RSDP address from boot params if availableJuergen Gross1-1/+2
In case the RSDP address in struct boot_params is specified don't try to find the table by searching, but take the address directly as set by the boot loader. Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boris.ostrovsky@oracle.com Cc: bp@alien8.de Cc: daniel.kiper@oracle.com Cc: sstabellini@kernel.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20181120072529.5489-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-20x86/boot: Mostly revert commit ae7e1238e68f2a ("Add ACPI RSDP address to setup_header")Juergen Gross1-4/+0
Peter Anvin pointed out that commit: ae7e1238e68f2a ("x86/boot: Add ACPI RSDP address to setup_header") should be reverted as setup_header should only contain items set by the legacy BIOS. So revert said commit. Instead of fully reverting the dependent commit of: e7b66d16fe4172 ("x86/acpi, x86/boot: Take RSDP address for boot params if available") just remove the setup_header reference in order to replace it by a boot_params in a followup patch. Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boris.ostrovsky@oracle.com Cc: bp@alien8.de Cc: daniel.kiper@oracle.com Cc: sstabellini@kernel.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20181120072529.5489-2-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-10x86/boot: Add ACPI RSDP address to setup_headerJuergen Gross1-0/+4
Xen PVH guests receive the address of the RSDP table from Xen. In order to support booting a Xen PVH guest via Grub2 using the standard x86 boot entry we need a way for Grub2 to pass the RSDP address to the kernel. For this purpose expand the struct setup_header to hold the physical address of the RSDP address. Being zero means it isn't specified and has to be located the legacy way (searching through low memory or EBDA). While documenting the new setup_header layout and protocol version 2.14 add the missing documentation of protocol version 2.13. There are Grub2 versions in several distros with a downstream patch violating the boot protocol by writing past the end of setup_header. This requires another update of the boot protocol to enable the kernel to distinguish between a specified RSDP address and one filled with garbage by such a broken Grub2. From protocol 2.14 on Grub2 will write the version it is supporting (but never a higher value than found to be supported by the kernel) ored with 0x8000 to the version field of setup_header. This enables the kernel to know up to which field Grub2 has written information to. All fields after that are supposed to be clobbered. Signed-off-by: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boris.ostrovsky@oracle.com Cc: bp@alien8.de Cc: corbet@lwn.net Cc: linux-doc@vger.kernel.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20181010061456.22238-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-05x86/uapi: Fix asm/bootparam.h userspace compilation errorsDmitry V. Levin1-9/+9
Consistently use types provided by <linux/types.h> to fix the following asm/bootparam.h userspace compilation errors: /usr/include/asm/bootparam.h:140:2: error: unknown type name 'u16' u16 version; /usr/include/asm/bootparam.h:141:2: error: unknown type name 'u16' u16 compatible_version; /usr/include/asm/bootparam.h:142:2: error: unknown type name 'u16' u16 pm_timer_address; /usr/include/asm/bootparam.h:143:2: error: unknown type name 'u16' u16 num_cpus; /usr/include/asm/bootparam.h:144:2: error: unknown type name 'u64' u64 pci_mmconfig_base; /usr/include/asm/bootparam.h:145:2: error: unknown type name 'u32' u32 tsc_khz; /usr/include/asm/bootparam.h:146:2: error: unknown type name 'u32' u32 apic_khz; /usr/include/asm/bootparam.h:147:2: error: unknown type name 'u8' u8 standard_ioapic; /usr/include/asm/bootparam.h:148:2: error: unknown type name 'u8' u8 cpu_ids[255]; Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Acked-by: Jan Kiszka <jan.kiszka@siemens.com> Cc: <stable@vger.kernel.org> # v4.16 Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 4a362601baa6 ("x86/jailhouse: Add infrastructure for running in non-root cell") Link: http://lkml.kernel.org/r/20180405043210.GA13254@altlinux.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-14x86/jailhouse: Add infrastructure for running in non-root cellJan Kiszka1-0/+22
The Jailhouse hypervisor is able to statically partition a multicore system into multiple so-called cells. Linux is used as boot loader and continues to run in the root cell after Jailhouse is enabled. Linux can also run in non-root cells. Jailhouse does not emulate usual x86 devices. It also provides no complex ACPI but basic platform information that the boot loader forwards via setup data. This adds the infrastructure to detect when running in a non-root cell so that the platform can be configured as required in succeeding steps. Support is limited to x86-64 so far, primarily because no boot loader stub exists for i386 and, thus, we wouldn't be able to test the 32-bit path. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: jailhouse-dev@googlegroups.com Link: https://lkml.kernel.org/r/7f823d077b38b1a70c526b40b403f85688c137d3.1511770314.git.jan.kiszka@siemens.com
2017-11-02License cleanup: add SPDX license identifier to uapi header files with no licenseGreg Kroah-Hartman1-0/+1
Many user space API headers are missing licensing information, which makes it hard for compliance tools to determine the correct license. By default are files without license information under the default license of the kernel, which is GPLV2. Marking them GPLV2 would exclude them from being included in non GPLV2 code, which is obviously not intended. The user space API headers fall under the syscall exception which is in the kernels COPYING file: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". otherwise syscall usage would not be possible. Update the files which contain no license information with an SPDX license identifier. The chosen identifier is 'GPL-2.0 WITH Linux-syscall-note' which is the officially assigned identifier for the Linux syscall exception. SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-24x86/lguest: Remove lguest supportJuergen Gross1-1/+1
Lguest seems to be rather unused these days. It has seen only patches ensuring it still builds the last two years and its official state is "Odd Fixes". Remove it in order to be able to clean up the paravirt code. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: boris.ostrovsky@oracle.com Cc: lguest@lists.ozlabs.org Cc: rusty@rustcorp.com.au Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20170816173157.8633-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-01Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-2/+16
Pull x86 boot updates from Ingo Molnar: "The biggest changes in this cycle were: - reworking of the e820 code: separate in-kernel and boot-ABI data structures and apply a whole range of cleanups to the kernel side. No change in functionality. - enable KASLR by default: it's used by all major distros and it's out of the experimental stage as well. - ... misc fixes and cleanups" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits) x86/KASLR: Fix kexec kernel boot crash when KASLR randomization fails x86/reboot: Turn off KVM when halting a CPU x86/boot: Fix BSS corruption/overwrite bug in early x86 kernel startup x86: Enable KASLR by default boot/param: Move next_arg() function to lib/cmdline.c for later reuse x86/boot: Fix Sparse warning by including required header file x86/boot/64: Rename start_cpu() x86/xen: Update e820 table handling to the new core x86 E820 code x86/boot: Fix pr_debug() API braindamage xen, x86/headers: Add <linux/device.h> dependency to <asm/xen/page.h> x86/boot/e820: Simplify e820__update_table() x86/boot/e820: Separate the E820 ABI structures from the in-kernel structures x86/boot/e820: Fix and clean up e820_type switch() statements x86/boot/e820: Rename the remaining E820 APIs to the e820__*() prefix x86/boot/e820: Remove unnecessary #include's x86/boot/e820: Rename e820_mark_nosave_regions() to e820__register_nosave_regions() x86/boot/e820: Rename e820_reserve_resources*() to e820__reserve_resources*() x86/boot/e820: Use bool in query APIs x86/boot/e820: Document e820__reserve_setup_data() x86/boot/e820: Clean up __e820__update_table() et al ...
2017-03-01x86/boot: Correct setup_header.start_sys nameBorislav Petkov1-1/+1
It is called start_sys_seg elsewhere so rename it to that. It is an obsolete field so we could just as well directly call it __u16 __pad... No functional change. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20170221183639.16554-1-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-01Merge branch 'linus' into WIP.x86/boot, to fix up conflicts and to pick up updatesIngo Molnar1-1/+2
Conflicts: arch/x86/xen/setup.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-07efi: Get and store the secure boot statusDavid Howells1-1/+2
Get the firmware's secure-boot status in the kernel boot wrapper and stash it somewhere that the main kernel image can find. The efi_get_secureboot() function is extracted from the ARM stub and (a) generalised so that it can be called from x86 and (b) made to use efi_call_runtime() so that it can be run in mixed-mode. For x86, it is stored in boot_params and can be overridden by the boot loader or kexec. This allows secure-boot mode to be passed on to a new kernel. Suggested-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1486380166-31868-5-git-send-email-ard.biesheuvel@linaro.org [ Small readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-29x86/boot/e820: Separate the E820 ABI structures from the in-kernel structuresIngo Molnar1-2/+16
Linus pointed out that relying on the compiler to pack structures with enums is fragile not just for the kernel, but for external tooling as well which might rely on our UAPI headers. So separate the two from each other: introduce 'struct boot_e820_entry', which is the boot protocol entry format. This actually simplifies the code, as e820__update_table() is now never called directly with boot protocol table entries - we can rely on append_e820_table() and do a e820__update_table() call afterwards. ( This will allow further simplifications of __e820__update_table(), but that will be done in a separate patch. ) This change also has the side effect of not modifying the bootparams structure anymore - which might be useful for debugging. In theory we could even constify the boot_params structure - at least from the E820 code's point of view. Remove the uapi/asm/e820/types.h file, as it's not used anymore - all kernel side E820 types are defined in asm/e820/types.h. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Paul Jackson <pj@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28x86/boot/e820: Clean up the E820 table size define namesIngo Molnar1-1/+1
We've got a number of defines related to the E820 table and its size: E820MAP E820NR E820_X_MAX E820MAX The first two denote byte offsets into the zeropage (struct boot_params), and can are not used in the kernel and can be removed. The E820_*_MAX values have an inconsistent structure and it's unclear in any case what they mean. 'X' presuably goes for extended - but it's not very expressive altogether. Change these over to: E820_MAX_ENTRIES_ZEROPAGE E820_MAX_ENTRIES ... which are self-explanatory names. No change in functionality. Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Jackson <pj@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28x86/boot/e820: Rename everything to e820_tableIngo Molnar1-1/+1
No change in functionality. Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Jackson <pj@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28x86/boot/e820: Rename 'e820_map' variables to 'e820_array'Ingo Molnar1-1/+1
In line with the rename to 'struct e820_array', harmonize the naming of common e820 table variable names as well: e820 => e820_array e820_saved => e820_array_saved e820_map => e820_array initial_e820 => e820_array_init This makes the variable names more consistent and easier to grep for. No change in functionality. Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Jackson <pj@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28x86/boot/e820: Rename the basic e820 data types to 'struct e820_entry' and 'struct e820_array'Ingo Molnar1-1/+1
The 'e820entry' and 'e820map' names have various annoyances: - the missing underscore departs from the usual kernel style and makes the code look weird, - in the past I kept confusing the 'map' with the 'entry', because a 'map' is ambiguous in that regard, - it's not really clear from the 'e820map' that this is a regular C array. Rename them to 'struct e820_entry' and 'struct e820_array' accordingly. ( Leave the legacy UAPI header alone but do the rename in the bootparam.h and e820/types.h file - outside tools relying on these defines should either adjust their code, or should use the legacy header, or should create their private copies for the definitions. ) No change in functionality. Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Jackson <pj@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28x86/boot/e820: Split minimal UAPI types out into uapi/asm/e820/types.hIngo Molnar1-1/+1
bootparam.h, which defines the legacy 'zeropage' boot parameter area, requires a small amount of e280 defines in the UAPI space - provide them. No change in functionality. Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Jackson <pj@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28x86/boot/e820: Move asm/e820.h to asm/e820/api.hIngo Molnar1-1/+1
In line with asm/e820/types.h, move the e820 API declarations to asm/e820/api.h and update all usage sites. This is just a mechanical, obviously correct move & replace patch, there will be subsequent changes to clean up the code and to make better use of the new header organization. Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Jackson <pj@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-13x86/efi: Retrieve and assign Apple device propertiesLukas Wunner1-0/+1
Apple's EFI drivers supply device properties which are needed to support Macs optimally. They contain vital information which cannot be obtained any other way (e.g. Thunderbolt Device ROM). They're also used to convey the current device state so that OS drivers can pick up where EFI drivers left (e.g. GPU mode setting). There's an EFI driver dubbed "AAPL,PathProperties" which implements a per-device key/value store. Other EFI drivers populate it using a custom protocol. The macOS bootloader /System/Library/CoreServices/boot.efi retrieves the properties with the same protocol. The kernel extension AppleACPIPlatform.kext subsequently merges them into the I/O Kit registry (see ioreg(8)) where they can be queried by other kernel extensions and user space. This commit extends the efistub to retrieve the device properties before ExitBootServices is called. It assigns them to devices in an fs_initcall so that they can be queried with the API in <linux/property.h>. Note that the device properties will only be available if the kernel is booted with the efistub. Distros should adjust their installers to always use the efistub on Macs. grub with the "linux" directive will not work unless the functionality of this commit is duplicated in grub. (The "linuxefi" directive should work but is not included upstream as of this writing.) The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and looks like this: typedef struct { unsigned long version; /* 0x10000 */ efi_status_t (*get) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name, OUT void *buffer, IN OUT u32 *buffer_len); /* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */ efi_status_t (*set) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name, IN void *property_value, IN u32 property_value_len); /* allocates copies of property name and value */ /* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */ efi_status_t (*del) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name); /* EFI_SUCCESS, EFI_NOT_FOUND */ efi_status_t (*get_all) ( IN struct apple_properties_protocol *this, OUT void *buffer, IN OUT u32 *buffer_len); /* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */ } apple_properties_protocol; Thanks to Pedro Vilaça for this blog post which was helpful in reverse engineering Apple's EFI drivers and bootloader: https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/ If someone at Apple is reading this, please note there's a memory leak in your implementation of the del() function as the property struct is freed but the name and value allocations are not. Neither the macOS bootloader nor Apple's EFI drivers check the protocol version, but we do to avoid breakage if it's ever changed. It's been the same since at least OS X 10.6 (2009). The get_all() function conveniently fills a buffer with all properties in marshalled form which can be passed to the kernel as a setup_data payload. The number of device properties is dynamic and can change between a first invocation of get_all() (to determine the buffer size) and a second invocation (to retrieve the actual buffer), hence the peculiar loop which does not finish until the buffer size settles. The macOS bootloader does the same. The setup_data payload is later on unmarshalled in an fs_initcall. The idea is that most buses instantiate devices in "subsys" initcall level and drivers are usually bound to these devices in "device" initcall level, so we assign the properties in-between, i.e. in "fs" initcall level. This assumes that devices to which properties pertain are instantiated from a "subsys" initcall or earlier. That should always be the case since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only supports ACPI and PCI nodes and we've fully scanned those buses during "subsys" initcall level. The second assumption is that properties are only needed from a "device" initcall or later. Seems reasonable to me, but should this ever not work out, an alternative approach would be to store the property sets e.g. in a btree early during boot. Then whenever device_add() is called, an EFI Device Path would have to be constructed for the newly added device, and looked up in the btree. That way, the property set could be assigned to the device immediately on instantiation. And this would also work for devices instantiated in a deferred fashion. It seems like this approach would be more complicated and require more code. That doesn't seem justified without a specific use case. For comparison, the strategy on macOS is to assign properties to objects in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()). That approach is definitely wrong as it fails for devices not present in the namespace: The NHI EFI driver supplies properties for attached Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device level behind the host controller is described in the namespace. Consequently macOS cannot assign properties for chained devices. With Thunderbolt 2 they started to describe three device levels behind host controllers in the namespace but this grossly inflates the SSDT and still fails if the user daisy-chained more than three devices. We copy the property names and values from the setup_data payload to swappable virtual memory and afterwards make the payload available to the page allocator. This is just for the sake of good housekeeping, it wouldn't occupy a meaningful amount of physical memory (4444 bytes on my machine). Only the payload is freed, not the setup_data header since otherwise we'd break the list linkage and we cannot safely update the predecessor's ->next link because there's no locking for the list. The payload is currently not passed on to kexec'ed kernels, same for PCI ROMs retrieved by setup_efi_pci(). This can be added later if there is demand by amending setup_efi_state(). The payload can then no longer be made available to the page allocator of course. Tested-by: Lukas Wunner <lukas@wunner.de> [MacBookPro9,1] Tested-by: Pierre Moreau <pierre.morrow@free.fr> [MacBookPro11,3] Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andreas Noever <andreas.noever@gmail.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pedro Vilaça <reverser@put.as> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: grub-devel@gnu.org Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20161112213237.8804-9-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-22x86/boot: Enumerate documentation for the x86 hardware_subarchLuis R. Rodriguez1-1/+40
Although hardware_subarch has been in place since the x86 boot protocol 2.07 it hasn't been used much. Enumerate current possible values to avoid misuses and help with semantics later at boot time should this be used further. These enums should only ever be used by architecture x86 code, and all that code should be well contained and compartamentalized, clarify that as well. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: andrew.cooper3@citrix.com Cc: andriy.shevchenko@linux.intel.com Cc: bigeasy@linutronix.de Cc: boris.ostrovsky@oracle.com Cc: david.vrabel@citrix.com Cc: ffainelli@freebox.fr Cc: george.dunlap@citrix.com Cc: glin@suse.com Cc: jgross@suse.com Cc: jlee@suse.com Cc: josh@joshtriplett.org Cc: julien.grall@linaro.org Cc: konrad.wilk@oracle.com Cc: kozerkov@parallels.com Cc: lenb@kernel.org Cc: lguest@lists.ozlabs.org Cc: linux-acpi@vger.kernel.org Cc: lv.zheng@intel.com Cc: matt@codeblueprint.co.uk Cc: mbizon@freebox.fr Cc: rjw@rjwysocki.net Cc: robert.moore@intel.com Cc: rusty@rustcorp.com.au Cc: tiwai@suse.de Cc: toshi.kani@hp.com Cc: xen-devel@lists.xensource.com Link: http://lkml.kernel.org/r/1460592286-300-2-git-send-email-mcgrof@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21x86/boot: Obsolete the MCA sys_desc_tablePaolo Pisati1-1/+1
The kernel does not support the MCA bus anymroe, so mark sys_desc_table as obsolete: remove any reference from the code together with the remaining of MCA logic. bloat-o-meter output: add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-55 (-55) function old new delta i386_start_kernel 128 119 -9 setup_arch 1421 1375 -46 Signed-off-by: Paolo Pisati <p.pisati@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1437409430-8491-1-git-send-email-p.pisati@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-03x86/mm/KASLR: Propagate KASLR status to kernel properBorislav Petkov1-0/+1
Commit: e2b32e678513 ("x86, kaslr: randomize module base load address") made module base address randomization unconditional and didn't regard disabled KKASLR due to CONFIG_HIBERNATION and command line option "nokaslr". For more info see (now reverted) commit: f47233c2d34f ("x86/mm/ASLR: Propagate base load address calculation") In order to propagate KASLR status to kernel proper, we need a single bit in boot_params.hdr.loadflags and we've chosen bit 1 thus leaving the top-down allocated bits for bits supposed to be used by the bootloader. Originally-From: Jiri Kosina <jkosina@suse.cz> Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-16Revert "x86/mm/ASLR: Propagate base load address calculation"Borislav Petkov1-1/+0
This reverts commit: f47233c2d34f ("x86/mm/ASLR: Propagate base load address calculation") The main reason for the revert is that the new boot flag does not work at all currently, and in order to make this work, we need non-trivial changes to the x86 boot code which we didn't manage to get done in time for merging. And even if we did, they would've been too risky so instead of rushing things and break booting 4.1 on boxes left and right, we will be very strict and conservative and will take our time with this to fix and test it properly. Reported-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Baoquan He <bhe@redhat.com> Cc: H. Peter Anvin <hpa@linux.intel.com Cc: Jiri Kosina <jkosina@suse.cz> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Junjie Mao <eternal.n08@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/20150316100628.GD22995@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-19x86/mm/ASLR: Propagate base load address calculationJiri Kosina1-0/+1
Commit: e2b32e678513 ("x86, kaslr: randomize module base load address") makes the base address for module to be unconditionally randomized in case when CONFIG_RANDOMIZE_BASE is defined and "nokaslr" option isn't present on the commandline. This is not consistent with how choose_kernel_location() decides whether it will randomize kernel load base. Namely, CONFIG_HIBERNATION disables kASLR (unless "kaslr" option is explicitly specified on kernel commandline), which makes the state space larger than what module loader is looking at. IOW CONFIG_HIBERNATION && CONFIG_RANDOMIZE_BASE is a valid config option, kASLR wouldn't be applied by default in that case, but module loader is not aware of that. Instead of fixing the logic in module.c, this patch takes more generic aproach. It introduces a new bootparam setup data_type SETUP_KASLR and uses that to pass the information whether kaslr has been applied during kernel decompression, and sets a global 'kaslr_enabled' variable accordingly, so that any kernel code (module loading, livepatching, ...) can make decisions based on its value. x86 module loader is converted to make use of this flag. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Kees Cook <keescook@chromium.org> Cc: "H. Peter Anvin" <hpa@linux.intel.com> Link: https://lkml.kernel.org/r/alpine.LNX.2.00.1502101411280.10719@pobox.suse.cz [ Always dump correct kaslr status when panicking ] Signed-off-by: Borislav Petkov <bp@suse.de>
2013-12-29x86: Add xloadflags bit for EFI runtime support on kexecDave Young1-0/+1
Old kexec-tools can not load new kernels. The reason is kexec-tools does not fill efi_info in x86 setup header previously, thus EFI failed to initialize. In new kexec-tools it will by default to fill efi_info and pass other EFI required infomation to 2nd kernel so kexec kernel EFI initialization can succeed finally. To prevent from breaking userspace, add a new xloadflags bit so kexec-tools can check the flag and switch to old logic. Signed-off-by: Dave Young <dyoung@redhat.com> Acked-by: Borislav Petkov <bp@suse.de> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-12-29x86/efi: Pass necessary EFI data for kexec via setup_dataDave Young1-0/+1
Add a new setup_data type SETUP_EFI for kexec use. Passing the saved fw_vendor, runtime, config tables and EFI runtime mappings. When entering virtual mode, directly mapping the EFI runtime regions which we passed in previously. And skip the step to call SetVirtualAddressMap(). Specially for HP z420 workstation we need save the smbios physical address. The kernel boot sequence proceeds in the following order. Step 2 requires efi.smbios to be the physical address. However, I found that on HP z420 EFI system table has a virtual address of SMBIOS in step 1. Hence, we need set it back to the physical address with the smbios in efi_setup_data. (When it is still the physical address, it simply sets the same value.) 1. efi_init() - Set efi.smbios from EFI system table 2. dmi_scan_machine() - Temporary map efi.smbios to access SMBIOS table 3. efi_enter_virtual_mode() - Map EFI ranges Tested on ovmf+qemu, lenovo thinkpad, a dell laptop and an HP z420 workstation. Signed-off-by: Dave Young <dyoung@redhat.com> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-10-17intel_mid: Renamed *mrst* to *intel_mid*Kuppuswamy Sathyanarayanan1-1/+1
mrst is used as common name to represent all intel_mid type soc's. But moorsetwon is just one of the intel_mid soc. So renamed them to use intel_mid. This patch mainly renames the variables and related functions that uses *mrst* prefix with *intel_mid*. To ensure that there are no functional changes, I have compared the objdump of related files before and after rename and found the only difference is symbol and name changes. Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Link: http://lkml.kernel.org/r/1382049336-21316-6-git-send-email-david.a.cohen@linux.intel.com Signed-off-by: David Cohen <david.a.cohen@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-06-10Modify UEFI anti-bricking codeMatthew Garrett1-1/+0
This patch reworks the UEFI anti-bricking code, including an effective reversion of cc5a080c and 31ff2f20. It turns out that calling QueryVariableInfo() from boot services results in some firmware implementations jumping to physical addresses even after entering virtual mode, so until we have 1:1 mappings for UEFI runtime space this isn't going to work so well. Reverting these gets us back to the situation where we'd refuse to create variables on some systems because they classify deleted variables as "used" until the firmware triggers a garbage collection run, which they won't do until they reach a lower threshold. This results in it being impossible to install a bootloader, which is unhelpful. Feedback from Samsung indicates that the firmware doesn't need more than 5KB of storage space for its own purposes, so that seems like a reasonable threshold. However, there's still no guarantee that a platform will attempt garbage collection merely because it drops below this threshold. It seems that this is often only triggered if an attempt to write generates a genuine EFI_OUT_OF_RESOURCES error. We can force that by attempting to create a variable larger than the remaining space. This should fail, but if it somehow succeeds we can then immediately delete it. I've tested this on the UEFI machines I have available, but I don't have a Samsung and so can't verify that it avoids the bricking problem. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> Signed-off-by: Lee, Chun-Y <jlee@suse.com> [ dummy variable cleanup ] Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-04-15efi: Pass boot services variable info to runtime codeMatthew Garrett1-0/+1
EFI variables can be flagged as being accessible only within boot services. This makes it awkward for us to figure out how much space they use at runtime. In theory we could figure this out by simply comparing the results from QueryVariableInfo() to the space used by all of our variables, but that fails if the platform doesn't garbage collect on every boot. Thankfully, calling QueryVariableInfo() while still inside boot services gives a more reliable answer. This patch passes that information from the EFI boot stub up to the efi platform code. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-01-27x86, boot: Define the 2.12 bzImage boot protocolH. Peter Anvin1-17/+46
Define the 2.12 bzImage boot protocol: add xloadflags and additional fields to allow the command line, initramfs and struct boot_params to live above the 4 GiB mark. The xloadflags now communicates if this is a 64-bit kernel with the legacy 64-bit entry point and which of the EFI handover entry points are supported. Avoid adding new read flags to loadflags because of claimed bootloaders testing the whole byte for == 1 to determine bzImageness at least until the issue can be researched further. This is based on patches by Yinghai Lu and David Woodhouse. Originally-by: Yinghai Lu <yinghai@kernel.org> Originally-by: David Woodhouse <dwmw2@infradead.org> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: David Woodhouse <dwmw2@infradead.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1359058816-7615-26-git-send-email-yinghai@kernel.org Cc: Rob Landley <rob@landley.net> Cc: Gokul Caushik <caushik1@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Joe Millenbach <jmillenbach@gmail.com>
2012-12-14UAPI: (Scripted) Disintegrate arch/x86/include/asmDavid Howells1-0/+139
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>