kernel.git/arch/x86/kernel/e820.c, branch linux-4.13.y

x86/boot/e820: Introduce the bootloader provided e820_table_firmware[] table

2017-07-05T08:09:02Z

Add the real e820_tabel_firmware[] that will not be modified by the kernel or the EFI boot stub under any circumstance. In addition to that modify the code so that e820_table_firmwarep[] is exposed via sysfs to represent the real firmware memory layout, rather than exposing the e820_table_kexec[] table. This fixes a hibernation bug/warning, which uses e820_table_kexec[] to check RAM layout consistency across hibernation/resume: The suspend kernel: [ 0.000000] e820: update [mem 0x76671018-0x76679457] usable ==> usable The resume kernel: [ 0.000000] e820: update [mem 0x7666f018-0x76677457] usable ==> usable ... [ 15.752088] PM: Using 3 thread(s) for decompression. [ 15.752088] PM: Loading and decompressing image data (471870 pages)... [ 15.764971] Hibernate inconsistent memory map detected! [ 15.770833] PM: Image mismatch: architecture specific data Actually it is safe to restore these pages because E820_TYPE_RAM and E820_TYPE_RESERVED_KERN are treated the same during hibernation, so the original e820 table provided by the bootloader is used for hibernation MD5 fingerprint checking. The side effect is that, this newly introduced variable might increase the kernel size at compile time. Suggested-by: Ingo Molnar Signed-off-by: Chen Yu Cc: Dave Young Cc: Len Brown Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Thomas Gleixner Cc: Xunlei Pang Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/boot/e820: Rename the e820_table_firmware to e820_table_kexec

2017-07-05T08:09:02Z

Currently the e820_table_firmware[] table is mainly used by the kexec, and it is not what it's supposed to be - despite its name it might be modified by the kernel. So change its name to e820_table_kexec[]. In the next patch we will introduce the real e820_table_firmware[] table. No functional change. Signed-off-by: Chen Yu Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Xunlei Pang Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/boot/e820: Avoid overwriting e820_table_firmware

2017-07-05T08:09:02Z

The following commit in 2013: 77ea8c948953 ("x86: Reserve setup_data ranges late after parsing memmap cmdline") has fixed the issue of losing setup_data information by deferring the e820_reserve_setup_data() call until the early params have been parsed. But this also introduced a new problem that, during early params parsing, the kexec kernel might fake a mptable and saves it into the e820_table_firmware[] table (without saving the mptable to the e820_table[]), however the subsequent invoking of e820_reserve_setup_data() will overwrite the e820_table_firmware[] according to the e820_table[], thus the fake mptable information is lost. Fix this issue by updating the e820_table_firmware[] according to the setup_data information, but without overwriting it. Signed-off-by: Chen Yu Cc: Dave Young Cc: Len Brown Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Thomas Gleixner Cc: Xunlei Pang Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/boot/e820: Remove a redundant self assignment

2017-04-14T09:43:21Z

Remove a redundant self assignment of table->nr_entries, it does nothing and is an artifact of code simplification re-work. Detected by CoverityScan, CID#1428450 ("Self assignment") Fixes: 441ac2f33dd7 ("x86/boot/e820: Simplify e820__update_table()") Signed-off-by: Colin Ian King Cc: kernel-janitors@vger.kernel.org Cc: Denys Vlasenko Link: http://lkml.kernel.org/r/20170413155912.12078-1-colin.king@canonical.com Signed-off-by: Thomas Gleixner

x86/boot: Fix pr_debug() API braindamage

2017-02-01T10:07:23Z

What looked like a straightforward conversion from printk(KERN_DEBUG, ...) to pr_debug() broke the boot log output: DMI: /M57SLI-S4, BIOS FF 01/24/2008 -e820: update [mem 0x00000000-0x00000fff] usable ==> reserved -e820: remove [mem 0x000a0000-0x000fffff] usable +usable ==> reserved +usable e820: last_pfn = 0x230000 max_arch_pfn = 0x400000000 ... x86/PAT: Configuration [0-7]: WB WC UC- UC WB WC UC- WT -e820: update [mem 0xd0000000-0xffffffff] usable ==> reserved +usable ==> reserved i.e. spurious (and nonsensical) kernel log entries were created... We need a pr_debug_and_I_mean_it() function which does nothing but printk(KERN_DEBUG... Signed-off-by: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org [ Wrote changelog. ] Signed-off-by: Ingo Molnar

x86/boot/e820: Simplify e820__update_table()

2017-01-30T08:49:28Z

- Remove the now unnecessary __e820__update_table() wrappery - Move statics out from function scope, to make the logic clearer - Rename local variables to be more in line with the rest of 820.c - Remove unnecessary local variables: old_nr, *nr_entries No change in functionality. Cc: Alex Thorlton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dan Williams Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Huang, Ying Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Paul Jackson Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Tejun Heo Cc: Thomas Gleixner Cc: Wei Yang Cc: Yinghai Lu Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/boot/e820: Separate the E820 ABI structures from the in-kernel structures

2017-01-29T12:39:32Z

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 Cc: Alex Thorlton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dan Williams Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Huang, Ying Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Paul Jackson Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Tejun Heo Cc: Thomas Gleixner Cc: Wei Yang Cc: Yinghai Lu Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/boot/e820: Fix and clean up e820_type switch() statements

2017-01-29T12:39:31Z

A test-build of e820.o with -Wswitch-enum shows the following warnings: arch/x86/kernel/e820.c: In function ‘e820_type_to_string’: arch/x86/kernel/e820.c:965:2: warning: enumeration value ‘E820_TYPE_RESERVED’ not handled in switch [-Wswitch-enum] switch (entry->type) { ^ arch/x86/kernel/e820.c: In function ‘e820_type_to_iomem_type’: arch/x86/kernel/e820.c:979:2: warning: enumeration value ‘E820_TYPE_RESERVED’ not handled in switch [-Wswitch-enum] switch (entry->type) { ^ arch/x86/kernel/e820.c: In function ‘e820_type_to_iores_desc’: arch/x86/kernel/e820.c:993:2: warning: enumeration value ‘E820_TYPE_RESERVED’ not handled in switch [-Wswitch-enum] switch (entry->type) { ^ arch/x86/kernel/e820.c: In function ‘do_mark_busy’: arch/x86/kernel/e820.c:1015:2: warning: enumeration value ‘E820_TYPE_RAM’ not handled in switch [-Wswitch-enum] switch (type) { ^ Here's the four warnings: - The one in e820_type_to_string() is a borderline bug, we should differentiate known-reserved E820 types from unknown types. Fix it by printing a separate message for unknown E820 types. - The ones in e820_type_to_iomem_type(), e820_type_to_iores_desc() and do_mark_busy() are worth documenting, at least to the extent of enumerating them explicitly. Cc: Alex Thorlton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dan Williams Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Huang, Ying Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Paul Jackson Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Tejun Heo Cc: Thomas Gleixner Cc: Wei Yang Cc: Yinghai Lu Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/boot/e820: Rename the remaining E820 APIs to the e820__*() prefix

2017-01-28T21:55:26Z

Three more renames left: e820_end_of_ram_pfn() => e820__end_of_ram_pfn() e820_end_of_low_ram_pfn() => e820__end_of_low_ram_pfn() e820_reallocate_tables() => e820__reallocate_tables() After this all E820 API calls are prefixed with "e820__", making it much easier to grep for E820 functionality in the kernel. No change in functionality. Cc: Alex Thorlton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dan Williams Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Huang, Ying Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Paul Jackson Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Tejun Heo Cc: Thomas Gleixner Cc: Wei Yang Cc: Yinghai Lu Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/boot/e820: Remove unnecessary #include's

2017-01-28T21:55:26Z

A number of headers were included into e820.c unnecessarily - remove them. No change in functionality. Cc: Alex Thorlton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dan Williams Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Huang, Ying Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Paul Jackson Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Tejun Heo Cc: Thomas Gleixner Cc: Wei Yang Cc: Yinghai Lu Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar