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MdeModulePkg/Core: fix guard page missing issue

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This issue is a regression one caused by a patch at

    425d25699b

That fix didn't take the 0 page to free into account, which still
needs to call UnsetGuardPage() even no memory needs to free.

The fix is just moving the calling of UnsetGuardPage() to the place
right after calling AdjustMemoryF().

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
(cherry picked from commit 1263ecf2ff)
This commit is contained in:
Jian J Wang
2018-01-26 19:47:14 +08:00
committed by Star Zeng
parent e8bfb85874
commit 1a8a1978ea
2 changed files with 11 additions and 12 deletions
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16
MdeModulePkg/Core/Dxe/Mem/Pool.c
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@ -642,15 +642,15 @@ CoreFreePoolPagesWithGuard (
NoPagesGuarded = NoPages;
AdjustMemoryF (&Memory, &NoPages);
//
// It's safe to unset Guard page inside memory lock because there should
// be no memory allocation occurred in updating memory page attribute at
// this point. And unsetting Guard page before free will prevent Guard
// page just freed back to pool from being allocated right away before
// marking it usable (from non-present to present).
//
UnsetGuardForMemory (MemoryGuarded, NoPagesGuarded);
if (NoPages > 0) {
//
// It's safe to unset Guard page inside memory lock because there should
// be no memory allocation occurred in updating memory page attribute at
// this point. And unsetting Guard page before free will prevent Guard
// page just freed back to pool from being allocated right away before
// marking it usable (from non-present to present).
//
UnsetGuardForMemory (MemoryGuarded, NoPagesGuarded);
CoreFreePoolPagesI (PoolType, Memory, NoPages);
}
}