[tip:irq/numa] x86: fix alloc_mptable()

From: tip-bot for Yinghai Lu
Date: Mon May 11 2009 - 05:53:53 EST


Commit-ID: ee214558c2e959781a406e76c5b34364da638e1d
Gitweb: http://git.kernel.org/tip/ee214558c2e959781a406e76c5b34364da638e1d
Author: Yinghai Lu <yinghai@xxxxxxxxxx>
AuthorDate: Wed, 6 May 2009 10:07:07 -0700
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Mon, 11 May 2009 10:35:07 +0200

x86: fix alloc_mptable()

Fix the conditions when we stop updating the mptable due to
running out of slots.

[ Impact: fix memory corruption / non-working update_mptable boot parameter ]

Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
LKML-Reference: <4A01C3BB.1000609@xxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
arch/x86/kernel/mpparse.c | 25 +++++++++----------------
1 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
index 70fd7e4..cd2a41a 100644
--- a/arch/x86/kernel/mpparse.c
+++ b/arch/x86/kernel/mpparse.c
@@ -870,24 +870,17 @@ static
inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
#endif /* CONFIG_X86_IO_APIC */

-static int check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length,
- int count)
+static int
+check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
{
- if (!mpc_new_phys) {
- pr_info("No spare slots, try to append...take your risk, "
- "new mpc_length %x\n", count);
- } else {
- if (count <= mpc_new_length)
- pr_info("No spare slots, try to append..., "
- "new mpc_length %x\n", count);
- else {
- pr_err("mpc_new_length %lx is too small\n",
- mpc_new_length);
- return -1;
- }
+ int ret = 0;
+
+ if (!mpc_new_phys || count <= mpc_new_length) {
+ WARN(1, "update_mptable: No spare slots (length: %x)\n", count);
+ return -1;
}

- return 0;
+ return ret;
}

static int __init replace_intsrc_all(struct mpc_table *mpc,
@@ -946,7 +939,7 @@ static int __init replace_intsrc_all(struct mpc_table *mpc,
} else {
struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
count += sizeof(struct mpc_intsrc);
- if (!check_slot(mpc_new_phys, mpc_new_length, count))
+ if (check_slot(mpc_new_phys, mpc_new_length, count) < 0)
goto out;
assign_to_mpc_intsrc(&mp_irqs[i], m);
mpc->length = count;
--
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