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| author | Krzysztof Mazur <krzysiek@podlesie.net> | 2015-11-06 14:18:36 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-12-09 13:42:56 -0500 |
| commit | 592e0bd55f25be1e96d091d822082d9ac70a32cb (patch) | |
| tree | 6f0153fa171c8899e2fd8906e00cf965402d355c | |
| parent | 5734b9b8f7a230d1cf4b4468aa33fd3466cbd077 (diff) | |
| download | lwn-592e0bd55f25be1e96d091d822082d9ac70a32cb.tar.gz lwn-592e0bd55f25be1e96d091d822082d9ac70a32cb.zip | |
x86/setup: Fix low identity map for >= 2GB kernel range
commit 68accac392d859d24adcf1be3a90e41f978bd54c upstream.
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>
Link: http://lkml.kernel.org/r/1446815916-22105-1-git-send-email-krzysiek@podlesie.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/x86/kernel/setup.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index e5cefe944946..040718106629 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1185,7 +1185,7 @@ 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(); |