iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/setup: Fix low identity map for >= 2GB kernel range

Browse Source 
The commit f5f3497cad8c extended the low identity mapping. However, if
the kernel uses more than 2 GB (VMSPLIT_2G_OPT or VMSPLIT_1G memory
split), the normal memory mapping is overwritten by the low identity
mapping causing a crash. To avoid overwritting, limit the low identity
map to cover only memory before kernel range (PAGE_OFFSET).

Fixes: f5f3497cad8c "x86/setup: Extend low identity map to cover whole kernel range
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1446815916-22105-1-git-send-email-krzysiek@podlesie.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Krzysztof Mazur 2015-11-06 14:18:36 +01:00 committed by Thomas Gleixner
parent f4e342c877
commit 68accac392
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/kernel/setup.c
View File

@ -1188,7 +1188,7 @@ void __init setup_arch(char **cmdline_p)
*/
clone_pgd_range(initial_page_table,
swapper_pg_dir + KERNEL_PGD_BOUNDARY,
KERNEL_PGD_PTRS);
min(KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
#endif
tboot_probe();