This command provides a way to traverse the entire page hierarchy by a
given virtual address on x86. In addition to qemu's commands info
tlb/info mem it provides the complete information about the paging
structure for an arbitrary virtual address. It supports 4KB/2MB/1GB and 5
level paging.
Here is an example output for 2MB success translation:
(gdb) translate-vm address
cr3:
cr3 binary data 0x1085be003
next entry physical address 0x1085be000
---
bit 3 page level write through False
bit 4 page level cache disabled False
level 4:
entry address 0xffff8881085be7f8
page entry binary data 0x800000010ac83067
next entry physical address 0x10ac83000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size False
bit 11 restart to ordinary False
bit 63 execute disable True
level 3:
entry address 0xffff88810ac83a48
page entry binary data 0x101af7067
next entry physical address 0x101af7000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size False
bit 11 restart to ordinary False
bit 63 execute disable False
level 2:
entry address 0xffff888101af7368
page entry binary data 0x80000001634008e7
page size 2MB
page physical address 0x163400000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size True
bit 6 page dirty True
bit 8 global translation False
bit 11 restart to ordinary True
bit 12 pat False
bits (59, 62) protection key 0
bit 63 execute disable True
[dmitrii.bundin.a@gmail.com: add SPDX line, other tweaks]
Link: https://lkml.kernel.org/r/20230113175151.22278-1-dmitrii.bundin.a@gmail.com
[akpm@linux-foundation.org: s/physicall/physical/]
Link: https://lkml.kernel.org/r/20230102171014.31408-1-dmitrii.bundin.a@gmail.com
Signed-off-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Acked by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When working on SoC bring-up, (a full) userspace may not be available,
making it hard to benchmark the CPU performance of the system under
development. Still, one may want to have a rough idea of the (relative)
performance of one or more CPU cores, especially when working on e.g. the
clock driver that controls the CPU core clock(s).
Hence make the classical Dhrystone 2.1 benchmark available as a Linux
kernel test module, based on[1].
When built-in, this benchmark can be run without any userspace present.
Parallel runs (run on multiple CPU cores) are supported, just kick the
"run" file multiple times.
Note that the actual figures depend on the configuration options that
control compiler optimization (e.g. CONFIG_CC_OPTIMIZE_FOR_SIZE vs.
CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE), and on the compiler options used when
building the kernel in general. Hence numbers may differ from those
obtained by running similar benchmarks in userspace.
[1] https://github.com/qris/dhrystone-deb.git
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lkml.kernel.org/r/4d07ad990740a5f1e426ce4566fb514f60ec9bdd.1670509558.git.geert+renesas@glider.be
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Gow <davidgow@google.com>
[geert+renesas@glider.be: fix uninitialized use of ret]
Link: https://lkml.kernel.org/r/alpine.DEB.2.22.394.2212190857310.137329@ramsan.of.borg
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull x86 fixes from Borislav Petkov:
- Make sure the poking PGD is pinned for Xen PV as it requires it this
way
- Fixes for two resctrl races when moving a task or creating a new
monitoring group
- Fix SEV-SNP guests running under HyperV where MTRRs are disabled to
not return a UC- type mapping type on memremap() and thus cause a
serious slowdown
- Fix insn mnemonics in bioscall.S now that binutils is starting to fix
confusing insn suffixes
* tag 'x86_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: fix poking_init() for Xen PV guests
x86/resctrl: Fix event counts regression in reused RMIDs
x86/resctrl: Fix task CLOSID/RMID update race
x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case
x86/boot: Avoid using Intel mnemonics in AT&T syntax asm
Pull EDAC fixes from Borislav Petkov:
- Fix the EDAC device's confusion in the polling setting units
- Fix a memory leak in highbank's probing function
* tag 'edac_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/highbank: Fix memory leak in highbank_mc_probe()
EDAC/device: Fix period calculation in edac_device_reset_delay_period()
Pull powerpc fixes from Michael Ellerman:
- Fix a build failure with some versions of ld that have an odd version
string
- Fix incorrect use of mutex in the IMC PMU driver
Thanks to Kajol Jain, Michael Petlan, Ojaswin Mujoo, Peter Zijlstra, and
Yang Yingliang.
* tag 'powerpc-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s/hash: Make stress_hpt_timer_fn() static
powerpc/imc-pmu: Fix use of mutex in IRQs disabled section
powerpc/boot: Fix incorrect version calculation issue in ld_version
Pull memblock fix from Mike Rapoport:
"memblock: always release pages to the buddy allocator in
memblock_free_late()
If CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, memblock_free_pages()
only releases pages to the buddy allocator if they are not in the
deferred range. This is correct for free pages (as defined by
for_each_free_mem_pfn_range_in_zone()) because free pages in the
deferred range will be initialized and released as part of the
deferred init process.
memblock_free_pages() is called by memblock_free_late(), which is used
to free reserved ranges after memblock_free_all() has run. All pages
in reserved ranges have been initialized at that point, and
accordingly, those pages are not touched by the deferred init process.
This means that currently, if the pages that memblock_free_late()
intends to release are in the deferred range, they will never be
released to the buddy allocator. They will forever be reserved.
In addition, memblock_free_pages() calls kmsan_memblock_free_pages(),
which is also correct for free pages but is not correct for reserved
pages. KMSAN metadata for reserved pages is initialized by
kmsan_init_shadow(), which runs shortly before memblock_free_all().
For both of these reasons, memblock_free_pages() should only be called
for free pages, and memblock_free_late() should call
__free_pages_core() directly instead.
One case where this issue can occur in the wild is EFI boot on x86_64.
The x86 EFI code reserves all EFI boot services memory ranges via
memblock_reserve() and frees them later via memblock_free_late()
(efi_reserve_boot_services() and efi_free_boot_services(),
respectively).
If any of those ranges happens to fall within the deferred init range,
the pages will not be released and that memory will be unavailable.
For example, on an Amazon EC2 t3.micro VM (1 GB) booting via EFI:
v6.2-rc2:
Node 0, zone DMA
spanned 4095
present 3999
managed 3840
Node 0, zone DMA32
spanned 246652
present 245868
managed 178867
v6.2-rc2 + patch:
Node 0, zone DMA
spanned 4095
present 3999
managed 3840
Node 0, zone DMA32
spanned 246652
present 245868
managed 222816 # +43,949 pages"
* tag 'fixes-2023-01-14' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
mm: Always release pages to the buddy allocator in memblock_free_late().
Pull kernel hardening fixes from Kees Cook:
- Fix CFI hash randomization with KASAN (Sami Tolvanen)
- Check size of coreboot table entry and use flex-array
* tag 'hardening-v6.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
kbuild: Fix CFI hash randomization with KASAN
firmware: coreboot: Check size of table entry and use flex-array
