From 7accd1f8649643caac8061cea24720b229a57417 Mon Sep 17 00:00:00 2001 From: Alexander Egorenkov Date: Tue, 15 Jun 2021 16:05:09 +0200 Subject: [PATCH] s390/boot: make _diag308_reset_dma() position-independent As a preparation for moving the .dma.data section from the decompressor to the decompressed kernel, the .dma.data section must be made relocatable by replacing absolute memory addressing with relative one. This is required in order to be able to relocate the DMA section to a memory address <= 2G as required by the hardware architecture. The DMA section must be relocated in case the decompressed kernel was loaded to an address >= 2G which can occur if KASAN is enabled. By making the whole DMA section position-independent we avoid applying relocations to it whenever it is moved to a different address, which becomes possible as soon as it becomes a part of the decompressed kernel. Signed-off-by: Alexander Egorenkov Acked-by: Heiko Carstens Signed-off-by: Heiko Carstens --- arch/s390/boot/text_dma.S | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/s390/boot/text_dma.S b/arch/s390/boot/text_dma.S index 5ff5fee02801..65e037ab7df5 100644 --- a/arch/s390/boot/text_dma.S +++ b/arch/s390/boot/text_dma.S @@ -127,6 +127,8 @@ restart_part2: larl %r4,.Lprefix # Restore prefix register spx 0(%r4) larl %r4,.Lcontinue_psw # Restore PSW flags + larl %r2,.Lcontinue + stg %r2,8(%r4) lpswe 0(%r4) .Lcontinue: BR_EX_DMA_r14 @@ -139,7 +141,7 @@ ENDPROC(_diag308_reset_dma) .align 8 .Lcontinue_psw: - .quad 0,.Lcontinue + .quad 0,0 .align 8 .Lctlreg0: -- 2.25.1