linux/arch/x86
Dave Hansen f3119b8302 x86/mpx: Fix 32-bit address space calculation
I received a bug report that running 32-bit MPX binaries on
64-bit kernels was broken.  I traced it down to this little code
snippet.  We were switching our "number of bounds directory
entries" calculation correctly.  But, we didn't switch the other
side of the calculation: the virtual space size.

This meant that we were calculating an absurd size for
bd_entry_virt_space() on 32-bit because we used the 64-bit
virt_space.

This was _also_ broken for 32-bit kernels running on 64-bit
hardware since boot_cpu_data.x86_virt_bits=48 even when running
in 32-bit mode.

Correct that and properly handle all 3 possible cases:

 1. 32-bit binary on 64-bit kernel
 2. 64-bit binary on 64-bit kernel
 3. 32-bit binary on 32-bit kernel

This manifested in having bounds tables not properly unmapped.
It "leaked" memory but had no functional impact otherwise.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
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>
Link: http://lkml.kernel.org/r/20151111181934.FA7FAC34@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-12 09:20:37 +01:00
..
boot * Make the EFI System Resource Table (ESRT) driver explicitly 2015-10-14 16:51:34 +02:00
configs Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-09-04 15:49:32 -07:00
crypto Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 20:50:26 -08:00
entry Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:23:56 -08:00
ia32 Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
include x86/irq: Probe for PIC presence before allocating descs for legacy IRQs 2015-11-07 10:37:37 +01:00
kernel x86/cpu: Call verify_cpu() after having entered long mode too 2015-11-07 10:45:02 +01:00
kvm Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 20:50:26 -08:00
lguest genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
lib Linux 4.3-rc1 2015-09-13 11:25:35 +02:00
math-emu Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
mm x86/mpx: Fix 32-bit address space calculation 2015-11-12 09:20:37 +01:00
net bpf: Make the bpf_prog_array_map more generic 2015-08-09 22:50:05 -07:00
oprofile
pci PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code" 2015-09-15 13:18:04 -05:00
platform Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:33:18 -08:00
power x86/ldt: Make modify_ldt synchronous 2015-07-31 10:23:23 +02:00
purgatory
ras x86/ras/mce_amd_inj: Inject bank 4 errors on the NBC 2015-10-12 16:15:48 +02:00
realmode
tools
um Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 18:59:10 -08:00
video
xen x86/vdso: Remove runtime 32-bit vDSO selection 2015-10-07 11:34:08 +02:00
.gitignore
Kbuild
Kconfig Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 18:59:10 -08:00
Kconfig.cpu x86/Kconfig/cpus: Fix/complete CPU type help texts 2015-10-21 11:12:56 +02:00
Kconfig.debug x86/mm: Warn on W^X mappings 2015-10-06 11:11:48 +02:00
Makefile x86/asm: Re-add parts of the manual CFI infrastructure 2015-10-09 09:41:05 +02:00
Makefile.um
Makefile_32.cpu