powerpc/32s: Allow mapping with BATs with DEBUG_PAGEALLOC

DEBUG_PAGEALLOC only manages RW data.

Text and RO data can still be mapped with BATs.

In order to map with BATs, also enforce data alignment. Set
by default to 256M which is a good compromise for keeping
enough BATs for also KASAN and IMMR.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fd29c1718ee44d82115d0e835ced808eb4ccbf51.1589866984.git.christophe.leroy@csgroup.eu
This commit is contained in:
Christophe Leroy 2020-05-19 05:49:28 +00:00 committed by Michael Ellerman
parent a2feeb2c2e
commit 2b279c0348
3 changed files with 9 additions and 3 deletions

View File

@ -797,6 +797,7 @@ config DATA_SHIFT
range 17 28 if (STRICT_KERNEL_RWX || DEBUG_PAGEALLOC) && PPC_BOOK3S_32
range 19 23 if (STRICT_KERNEL_RWX || DEBUG_PAGEALLOC) && PPC_8xx
default 22 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
default 18 if DEBUG_PAGEALLOC && PPC_BOOK3S_32
default 23 if STRICT_KERNEL_RWX && PPC_8xx
default 23 if DEBUG_PAGEALLOC && PPC_8xx && PIN_TLB_DATA
default 19 if DEBUG_PAGEALLOC && PPC_8xx

View File

@ -170,6 +170,12 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
pr_debug("RAM mapped without BATs\n");
return base;
}
if (debug_pagealloc_enabled()) {
if (base >= border)
return base;
if (top >= border)
top = border;
}
if (!strict_kernel_rwx_enabled() || base >= border || top <= border)
return __mmu_mapin_ram(base, top);

View File

@ -99,10 +99,9 @@ static void __init MMU_setup(void)
if (IS_ENABLED(CONFIG_PPC_8xx))
return;
if (debug_pagealloc_enabled()) {
__map_without_bats = 1;
if (debug_pagealloc_enabled())
__map_without_ltlbs = 1;
}
if (strict_kernel_rwx_enabled())
__map_without_ltlbs = 1;
}