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author | Ingo Molnar <mingo@kernel.org> | 2024-03-25 11:47:51 +0100 |
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committer | Ingo Molnar <mingo@kernel.org> | 2024-03-25 11:54:35 +0100 |
commit | c567f2948f57bdc03ed03403ae0234085f376b7d (patch) | |
tree | c77676f421fbfe2cbb946bdb3a439f51202214a8 /arch | |
parent | Documentation/x86: Fix title underline length (diff) | |
download | linux-c567f2948f57bdc03ed03403ae0234085f376b7d.tar.xz linux-c567f2948f57bdc03ed03403ae0234085f376b7d.zip |
Revert "x86/mm/ident_map: Use gbpages only where full GB page should be mapped."
This reverts commit d794734c9bbfe22f86686dc2909c25f5ffe1a572.
While the original change tries to fix a bug, it also unintentionally broke
existing systems, see the regressions reported at:
https://lore.kernel.org/all/3a1b9909-45ac-4f97-ad68-d16ef1ce99db@pavinjoseph.com/
Since d794734c9bbf was also marked for -stable, let's back it out before
causing more damage.
Note that due to another upstream change the revert was not 100% automatic:
0a845e0f6348 mm/treewide: replace pud_large() with pud_leaf()
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Russ Anderson <rja@hpe.com>
Cc: Steve Wahl <steve.wahl@hpe.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/3a1b9909-45ac-4f97-ad68-d16ef1ce99db@pavinjoseph.com/
Fixes: d794734c9bbf ("x86/mm/ident_map: Use gbpages only where full GB page should be mapped.")
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/mm/ident_map.c | 23 |
1 files changed, 5 insertions, 18 deletions
diff --git a/arch/x86/mm/ident_map.c b/arch/x86/mm/ident_map.c index a204a332c71f..968d7005f4a7 100644 --- a/arch/x86/mm/ident_map.c +++ b/arch/x86/mm/ident_map.c @@ -26,31 +26,18 @@ static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page, for (; addr < end; addr = next) { pud_t *pud = pud_page + pud_index(addr); pmd_t *pmd; - bool use_gbpage; next = (addr & PUD_MASK) + PUD_SIZE; if (next > end) next = end; - /* if this is already a gbpage, this portion is already mapped */ - if (pud_leaf(*pud)) - continue; - - /* Is using a gbpage allowed? */ - use_gbpage = info->direct_gbpages; - - /* Don't use gbpage if it maps more than the requested region. */ - /* at the begining: */ - use_gbpage &= ((addr & ~PUD_MASK) == 0); - /* ... or at the end: */ - use_gbpage &= ((next & ~PUD_MASK) == 0); - - /* Never overwrite existing mappings */ - use_gbpage &= !pud_present(*pud); - - if (use_gbpage) { + if (info->direct_gbpages) { pud_t pudval; + if (pud_present(*pud)) + continue; + + addr &= PUD_MASK; pudval = __pud((addr - info->offset) | info->page_flag); set_pud(pud, pudval); continue; |