Commit Graph

5 Commits

Author SHA1 Message Date
John David Anglin
1753a49e26 parisc: Fix patch code locking and flushing
[ Upstream commit a9fe7fa7d874a536e0540469f314772c054a0323 ]

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 <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 21:01:03 +02:00
Sven Schnelle
7e923369b1 parisc: add spinlock to patch function
If multiple CPUs are patching code we need the spinlock
to protect against parallel fixmap maps/unmap calls.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2019-06-08 12:56:26 +02:00
Sven Schnelle
4e87ace902 parisc: add support for patching multiple words
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 <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2019-06-08 12:56:25 +02:00
Sven Schnelle
ea5a8c620f parisc: remove unused flags parameter in __patch_text()
It's not used by patch_map()/patch_unmap(), so lets remove
it.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2019-05-03 23:47:39 +02:00
Sven Schnelle
620a53d522 parisc: add parisc code patching
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 <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2019-05-03 23:47:38 +02:00