From 43b78f1155c868208a413082179251f5fba78153 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Fri, 4 May 2018 14:35:12 -0700
Subject: [PATCH] Revert "usb: host: ehci: Use dma_pool_zalloc()"
This reverts commit 22072e83ebd510fb6a090aef9d65ccfda9b1e7e4 as it is
broken.
Alan writes:
What you can't see just from reading the patch is that in both
cases (ehci->itd_pool and ehci->sitd_pool) there are two
allocation paths -- the two branches of an "if" statement -- and
only one of the paths calls dma_pool_[z]alloc. However, the
memset is needed for both paths, and so it can't be eliminated.
Given that it must be present, there's no advantage to calling
dma_pool_zalloc rather than dma_pool_alloc.
Reported-by: Erick Cafferata <erick@cafferata.me>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/host/ehci-mem.c | 3 ++-
drivers/usb/host/ehci-sched.c | 6 ++++--
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/host/ehci-mem.c b/drivers/usb/host/ehci-mem.c
index 4c6c08b675b5c..21307d862af67 100644
--- a/drivers/usb/host/ehci-mem.c
+++ b/drivers/usb/host/ehci-mem.c
@@ -73,9 +73,10 @@ static struct ehci_qh *ehci_qh_alloc (struct ehci_hcd *ehci, gfp_t flags)
if (!qh)
goto done;
qh->hw = (struct ehci_qh_hw *)
- dma_pool_zalloc(ehci->qh_pool, flags, &dma);
+ dma_pool_alloc(ehci->qh_pool, flags, &dma);
if (!qh->hw)
goto fail;
+ memset(qh->hw, 0, sizeof *qh->hw);
qh->qh_dma = dma;
// INIT_LIST_HEAD (&qh->qh_list);
INIT_LIST_HEAD (&qh->qtd_list);
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 28e2a338b4815..e56db44708bcc 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -1287,7 +1287,7 @@ itd_urb_transaction(
} else {
alloc_itd:
spin_unlock_irqrestore(&ehci->lock, flags);
- itd = dma_pool_zalloc(ehci->itd_pool, mem_flags,
+ itd = dma_pool_alloc(ehci->itd_pool, mem_flags,
&itd_dma);
spin_lock_irqsave(&ehci->lock, flags);
if (!itd) {
@@ -1297,6 +1297,7 @@ itd_urb_transaction(
}
}
+ memset(itd, 0, sizeof(*itd));
itd->itd_dma = itd_dma;
itd->frame = NO_FRAME;
list_add(&itd->itd_list, &sched->td_list);
@@ -2080,7 +2081,7 @@ sitd_urb_transaction(
} else {
alloc_sitd:
spin_unlock_irqrestore(&ehci->lock, flags);
- sitd = dma_pool_zalloc(ehci->sitd_pool, mem_flags,
+ sitd = dma_pool_alloc(ehci->sitd_pool, mem_flags,
&sitd_dma);
spin_lock_irqsave(&ehci->lock, flags);
if (!sitd) {
@@ -2090,6 +2091,7 @@ sitd_urb_transaction(
}
}
+ memset(sitd, 0, sizeof(*sitd));
sitd->sitd_dma = sitd_dma;
sitd->frame = NO_FRAME;
list_add(&sitd->sitd_list, &iso_sched->td_list);
--
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