This change fixes the following:
1) The flags variable is not initialized. Always use raw_spin_lock_irqsave
and raw_spin_unlock_irqrestore to serialize patching.
2) flush_kernel_vmap_range is primarily intended for DMA flushes.
The whole cache flush in flush_kernel_vmap_range is only possible
when interrupts are enabled on SMP machines. Since __patch_text_multiple
calls flush_kernel_vmap_range with interrupts disabled, it is better
to directly call flush_kernel_dcache_range_asm and
flush_kernel_icache_range_asm.
3) The final call to flush_icache_range is unnecessary.
Tested with `[PATCH, V3] parisc: Rewrite cache flush code for
PA8800/PA8900' change on rp3440, c8000 and c3750 (32 and 64-bit).
Note by Helge:
This patch had been temporarily reverted shortly before v5.18-rc6 in order
to fix boot issues. Now it can be re-applied.
Signed-off-by: John David Anglin <[email protected]>
Signed-off-by: Helge Deller <[email protected]>
This change fixes the following:
1) The flags variable is not initialized. Always use raw_spin_lock_irqsave
and raw_spin_unlock_irqrestore to serialize patching.
2) flush_kernel_vmap_range is primarily intended for DMA flushes. Since
__patch_text_multiple is often called with interrupts disabled, it is
better to directly call flush_kernel_dcache_range_asm and
flush_kernel_icache_range_asm. This avoids an extra call.
3) The final call to flush_icache_range is unnecessary.
Signed-off-by: John David Anglin <[email protected]>
Signed-off-by: Helge Deller <[email protected]>
If multiple CPUs are patching code we need the spinlock
to protect against parallel fixmap maps/unmap calls.
Signed-off-by: Sven Schnelle <[email protected]>
Signed-off-by: Helge Deller <[email protected]>
add patch_text_multiple() which allows to patch multiple
text words in memory. This can be used to copy functions.
Signed-off-by: Sven Schnelle <[email protected]>
Signed-off-by: Helge Deller <[email protected]>
It's not used by patch_map()/patch_unmap(), so lets remove
it.
Signed-off-by: Sven Schnelle <[email protected]>
Signed-off-by: Helge Deller <[email protected]>
Instead of re-mapping the whole kernel text with RWX rights
add a patch_text() which can be used to replace instructions
in the kernel .text section. Based on the ARM implementation.
Signed-off-by: Sven Schnelle <[email protected]>
Signed-off-by: Helge Deller <[email protected]>
Mike Rapoport (Microsoft)