diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2019-10-23 12:02:47 +0200 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2019-10-23 12:10:05 +0200 |
| commit | 2e79e22e092acd55da0b2db066e4826d7d152c41 (patch) | |
| tree | e7ec9782c0b7831c511af711424126a2b9a4eb07 /arch/x86/kernel/head64.c | |
| parent | f1b4a9217efd61d0b84c6dc404596c8519ff6f59 (diff) | |
| parent | 7d194c2100ad2a6dded545887d02754948ca5241 (diff) | |
Merge v5.4-rc4 into drm-next
Thierry needs fd70c7755bf0 ("drm/bridge: tc358767: fix max_tu_symbol
value") to be able to merge his dp_link patch series.
Some adjacent changes conflicts, plus some clashes in i915 due to
cherry-picking and git trying to be helpful and leaving both versions
in.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'arch/x86/kernel/head64.c')
| -rw-r--r-- | arch/x86/kernel/head64.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 29ffa495bd1c..206a4b6144c2 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -222,13 +222,31 @@ unsigned long __head __startup_64(unsigned long physaddr, * we might write invalid pmds, when the kernel is relocated * cleanup_highmap() fixes this up along with the mappings * beyond _end. + * + * Only the region occupied by the kernel image has so far + * been checked against the table of usable memory regions + * provided by the firmware, so invalidate pages outside that + * region. A page table entry that maps to a reserved area of + * memory would allow processor speculation into that area, + * and on some hardware (particularly the UV platform) even + * speculative access to some reserved areas is caught as an + * error, causing the BIOS to halt the system. */ pmd = fixup_pointer(level2_kernel_pgt, physaddr); - for (i = 0; i < PTRS_PER_PMD; i++) { + + /* invalidate pages before the kernel image */ + for (i = 0; i < pmd_index((unsigned long)_text); i++) + pmd[i] &= ~_PAGE_PRESENT; + + /* fixup pages that are part of the kernel image */ + for (; i <= pmd_index((unsigned long)_end); i++) if (pmd[i] & _PAGE_PRESENT) pmd[i] += load_delta; - } + + /* invalidate pages after the kernel image */ + for (; i < PTRS_PER_PMD; i++) + pmd[i] &= ~_PAGE_PRESENT; /* * Fixup phys_base - remove the memory encryption mask to obtain |