* John David Anglin <dave.anglin@xxxxxxxx>: > The extru instruction leaves the most significant 32 bits of the target register in an undefined > state on PA 2.0 systems. If any of these bits are nonzero, this will break the calculation of the > lock pointer. > > Fix by using extrd,u instruction on 64-bit kernels. I wonder if we shouldn't introduce an extru_safe() macro. The name doesn't matter, but that way we can get rid of the ifdefs and use it in other places as well, e.g. as seen below. Thoughs? Helge diff --git a/arch/parisc/include/asm/assembly.h b/arch/parisc/include/asm/assembly.h index 7085df079702..9c5f0fc67400 100644 --- a/arch/parisc/include/asm/assembly.h +++ b/arch/parisc/include/asm/assembly.h @@ -143,6 +143,16 @@ extrd,u \r, 63-(\sa), 64-(\sa), \t .endm + /* The extru instruction leaves the most significant 32 bits of the + * target register in an undefined state on PA 2.0 systems. */ + .macro extru_safe r, p, len, t +#ifdef CONFIG_64BIT + extrd,u \r, 32+(\p), \len, \t +#else + extru \r, \p, \len, \t +#endif + .endm + /* load 32-bit 'value' into 'reg' compensating for the ldil * sign-extension when running in wide mode. * WARNING!! neither 'value' nor 'reg' can be expressions diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index 88c188a965d8..6e9cdb269862 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -366,17 +366,9 @@ */ .macro L2_ptep pmd,pte,index,va,fault #if CONFIG_PGTABLE_LEVELS == 3 - extru \va,31-ASM_PMD_SHIFT,ASM_BITS_PER_PMD,\index + extru_safe \va,31-ASM_PMD_SHIFT,ASM_BITS_PER_PMD,\index #else -# if defined(CONFIG_64BIT) - extrd,u \va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index - #else - # if PAGE_SIZE > 4096 - extru \va,31-ASM_PGDIR_SHIFT,32-ASM_PGDIR_SHIFT,\index - # else - extru \va,31-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index - # endif -# endif + extru_safe \va,31-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index #endif dep %r0,31,PAGE_SHIFT,\pmd /* clear offset */ #if CONFIG_PGTABLE_LEVELS < 3 @@ -386,7 +378,7 @@ bb,>=,n \pmd,_PxD_PRESENT_BIT,\fault dep %r0,31,PxD_FLAG_SHIFT,\pmd /* clear flags */ SHLREG \pmd,PxD_VALUE_SHIFT,\pmd - extru \va,31-PAGE_SHIFT,ASM_BITS_PER_PTE,\index + extru_safe \va,31-PAGE_SHIFT,ASM_BITS_PER_PTE,\index dep %r0,31,PAGE_SHIFT,\pmd /* clear offset */ shladd \index,BITS_PER_PTE_ENTRY,\pmd,\pmd /* pmd is now pte */ .endm diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S index 4fb3b6a993bf..d2497b339d13 100644 --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -566,7 +566,7 @@ lws_compare_and_swap: ldo R%lws_lock_start(%r20), %r28 /* Extract eight bits from r26 and hash lock (Bits 3-11) */ - extru %r26, 28, 8, %r20 + extru_safe %r26, 28, 8, %r20 /* Find lock to use, the hash is either one of 0 to 15, multiplied by 16 (keep it 16-byte aligned) @@ -751,7 +751,7 @@ cas2_lock_start: ldo R%lws_lock_start(%r20), %r28 /* Extract eight bits from r26 and hash lock (Bits 3-11) */ - extru %r26, 28, 8, %r20 + extru_safe %r26, 28, 8, %r20 /* Find lock to use, the hash is either one of 0 to 15, multiplied by 16 (keep it 16-byte aligned)
