| Message ID | 27edd227d3b9dcda4e2ce7d00d9fddeb7a5520a1.1545241146.git.christophe.leroy@c-s.fr (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | powerpc/8xx: Map a second 8M text page at startup when needed. | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | next/apply_patch Successfully applied |
| snowpatch_ozlabs/build-ppc64le | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/build-ppc64be | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/build-ppc64e | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/build-pmac32 | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 49 lines checked |
On Thu, Dec 20, 2018 at 05:48:25AM +0000, Christophe Leroy wrote: > Some debug setup like CONFIG_KASAN generate huge > kernels with text size over the 8M limit. > > This patch maps a second 8M page when _einittext is over 8M. Do we also need a check to generate a useful warning if we ever overflow the 16MB?
Le 20/12/2018 à 09:24, Christoph Hellwig a écrit : > On Thu, Dec 20, 2018 at 05:48:25AM +0000, Christophe Leroy wrote: >> Some debug setup like CONFIG_KASAN generate huge >> kernels with text size over the 8M limit. >> >> This patch maps a second 8M page when _einittext is over 8M. > > Do we also need a check to generate a useful warning if we ever overflow > the 16MB? > I don't think any other platform does that (the 40x also maps 16Mb, book3s/601 maps 24Mb) But why not, could do that in another patch. Is there an easy way to get the link to fail when CONFIG_PIN_TLB_TEXT is set and _einittext is higher than 16Mb ? Or should we just map up to 24Mb on the 8xx and consider we are on the safe side with that much ? Christophe
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index b171b7c0a0e7..f6bc4392ea9f 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -334,8 +334,8 @@ InstructionTLBMiss: rlwinm r10, r10, 16, 0xfff8 cmpli cr0, r10, PAGE_OFFSET@h #ifndef CONFIG_PIN_TLB_TEXT - /* It is assumed that kernel code fits into the first 8M page */ -0: cmpli cr7, r10, (PAGE_OFFSET + 0x0800000)@h + /* It is assumed that kernel code fits into the two first 8M pages */ +0: cmpli cr7, r10, (PAGE_OFFSET + 0x1000000)@h patch_site 0b, patch__itlbmiss_linmem_top #endif #endif @@ -904,6 +904,29 @@ initial_mmu: li r8, MI_BOOTINIT /* Create RPN for address 0 */ mtspr SPRN_MI_RPN, r8 /* Store TLB entry */ + /* Map a second 8M page if needed */ + lis r9, _einittext@h + oris r9, r9, _einittext@l + cmpli cr0, r9, (PAGE_OFFSET + 0x8000000)@h + blt 1f + +#ifdef CONFIG_PIN_TLB_TEXT + lis r8, MI_RSV4I@h + ori r8, r8, 0x1d00 + + mtspr SPRN_MI_CTR, r8 /* Set instruction MMU control */ +#endif + + lis r8, (KERNELBASE + 0x800000)@h /* Create vaddr for TLB */ + ori r8, r8, MI_EVALID /* Mark it valid */ + mtspr SPRN_MI_EPN, r8 + li r8, MI_PS8MEG /* Set 8M byte page */ + ori r8, r8, MI_SVALID /* Make it valid */ + mtspr SPRN_MI_TWC, r8 + li r8, MI_BOOTINIT /* Create RPN for address 0 */ + addis r8, r8, 0x80 + mtspr SPRN_MI_RPN, r8 /* Store TLB entry */ +1: lis r8, MI_APG_INIT@h /* Set protection modes */ ori r8, r8, MI_APG_INIT@l mtspr SPRN_MI_AP, r8 diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c index e2b6687ebb50..1bdbfbf9fe16 100644 --- a/arch/powerpc/mm/8xx_mmu.c +++ b/arch/powerpc/mm/8xx_mmu.c @@ -122,6 +122,10 @@ unsigned long __init mmu_mapin_ram(unsigned long top) #endif } else { mapped = top & ~(LARGE_PAGE_SIZE_8M - 1); +#ifndef CONFIG_PIN_TLB_TEXT + mmu_patch_cmp_limit(&patch__itlbmiss_linmem_top, + _ALIGN(__pa(_einittext), 8 << 20)); +#endif } mmu_patch_cmp_limit(&patch__dtlbmiss_linmem_top, mapped);
Some debug setup like CONFIG_KASAN generate huge kernels with text size over the 8M limit. This patch maps a second 8M page when _einittext is over 8M. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> --- arch/powerpc/kernel/head_8xx.S | 27 +++++++++++++++++++++++++-- arch/powerpc/mm/8xx_mmu.c | 4 ++++ 2 files changed, 29 insertions(+), 2 deletions(-)