summaryrefslogtreecommitdiff
path: root/arch/parisc/kernel/patch.c
AgeCommit message (Collapse)Author
2022-05-17parisc: Fix patch code locking and flushingJohn David Anglin
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 <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de>
2022-05-08Revert "parisc: Fix patch code locking and flushing"Helge Deller
This reverts commit a9fe7fa7d874a536e0540469f314772c054a0323. Leads to segfaults on 32bit kernel. Signed-off-by: Helge Deller <deller@gmx.de>
2022-03-29parisc: Fix patch code locking and flushingJohn David Anglin
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>
2019-06-08parisc: add spinlock to patch functionSven Schnelle
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>
2019-06-08parisc: add support for patching multiple wordsSven Schnelle
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>
2019-05-03parisc: remove unused flags parameter in __patch_text()Sven Schnelle
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>
2019-05-03parisc: add parisc code patchingSven Schnelle
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>