linux/arch/x86/lib
Ricardo Neri bd5a410a5d x86/insn-eval: Add utility functions to get segment descriptor base address and limit
With segmentation, the base address of the segment is needed to compute a
linear address. This base address is obtained from the applicable segment
descriptor. Such segment descriptor is referenced from a segment selector.
These new functions obtain the segment base and limit of the segment
selector indicated by segment register index given as argument. This index
is any of the INAT_SEG_REG_* family of #define's.

The logic to obtain the segment selector is wrapped in the function
get_segment_selector() with the inputs described above. Once the selector
is known, the base address is determined. In protected mode, the selector
is used to obtain the segment descriptor and then its base address. In
long mode, the segment base address is zero except when FS or GS are used.
In virtual-8086 mode, the base address is computed as the value of the
segment selector shifted 4 positions to the left.

In protected mode, segment limits are enforced. Thus, a function to
determine the limit of the segment is added. Segment limits are not
enforced in long or virtual-8086. For the latter, addresses are limited
to 20 bits; address size will be handled when computing the linear
address.

Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: ricardo.neri@intel.com
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Garnier <thgarnie@google.com>
Link: https://lkml.kernel.org/r/1509135945-13762-16-git-send-email-ricardo.neri-calderon@linux.intel.com
2017-11-01 21:50:12 +01:00
..
.gitignore x86: Gitignore: arch/x86/lib/inat-tables.c 2009-11-04 13:11:28 +01:00
atomic64_32.c x86: Adjust asm constraints in atomic64 wrappers 2012-01-20 17:29:31 -08:00
atomic64_386_32.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
atomic64_cx8_32.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
cache-smp.c x86/lib: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:58 +02:00
checksum_32.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
clear_page_64.S x86/asm: Optimize clear_page() 2017-03-07 08:28:00 +01:00
cmdline.c x86/boot: Add early cmdline parsing for options with arguments 2017-07-18 11:38:06 +02:00
cmpxchg8b_emu.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
cmpxchg16b_emu.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
copy_page_64.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
copy_user_64.S x86/uaccess: Optimize copy_user_enhanced_fast_string() for short strings 2017-06-30 09:52:51 +02:00
cpu.c x86/lib: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:58 +02:00
csum-copy_64.S x86/asm: Don't use RBP as a temporary register in csum_partial_copy_generic() 2017-05-05 07:59:24 +02:00
csum-partial_64.c x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
csum-wrappers_64.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
delay.c Prevent timer value 0 for MWAITX 2017-04-30 13:35:11 +02:00
getuser.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
hweight.S Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-10-14 14:26:58 -07:00
inat.c x86: Fix to decode grouped AVX with VEX pp bits 2012-02-11 15:11:35 +01:00
insn-eval.c x86/insn-eval: Add utility functions to get segment descriptor base address and limit 2017-11-01 21:50:12 +01:00
insn.c x86/insn: Add AVX-512 support to the instruction decoder 2016-07-21 09:37:11 -03:00
iomap_copy_64.S x86/debug: Remove perpetually broken, unmaintainable dwarf annotations 2015-06-02 07:57:48 +02:00
kaslr.c x86/mm/kaslr: Use the _ASM_MUL macro for multiplication to work around Clang incompatibility 2017-05-05 08:31:05 +02:00
Makefile x86/mpx, x86/insn: Relocate insn util functions to a new insn-eval file 2017-11-01 21:50:10 +01:00
memcpy_32.c include/linux/string.h: add the option of fortified string.h functions 2017-07-12 16:26:03 -07:00
memcpy_64.S x86/mce: Fix copy/paste error in exception table entries 2017-03-22 08:43:25 +01:00
memmove_64.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
memset_64.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
misc.c x86/boot: Further compress CPUs bootup message 2013-10-01 10:52:30 +02:00
mmx_32.c x86/lib: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:58 +02:00
msr-reg-export.c x86/lib: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:58 +02:00
msr-reg.S objtool, x86: Add several functions and files to the objtool whitelist 2017-06-30 10:19:19 +02:00
msr-smp.c x86/lib: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:58 +02:00
msr.c x86/msr: Cleanup/streamline MSR helpers 2016-11-16 10:23:02 +01:00
putuser.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
rwsem.S locking/rwsem: Fix comment on register clobbering 2016-05-16 12:35:40 +02:00
string_32.c x86/lib: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:58 +02:00
strstr_32.c x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
usercopy_32.c x86: switch to RAW_COPY_USER 2017-03-29 12:06:28 -04:00
usercopy_64.c x86, dax, libnvdimm: remove wb_cache_pmem() indirection 2017-06-15 14:35:24 -07:00
usercopy.c x86: switch to RAW_COPY_USER 2017-03-29 12:06:28 -04:00
x86-opcode-map.txt x86/insn: perf tools: Add new ptwrite instruction 2017-06-27 11:58:04 -03:00