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| author | Greg Pearson <greg.pearson@hp.com> | 2012-07-30 14:39:05 -0700 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2012-08-10 00:25:00 +0100 |
| commit | ffb709e6aa95c3ba44fa8af9f7815e3c6cfed04e (patch) | |
| tree | c440b29b50a2a2f64c204b490d1373ffaac5f4d3 /drivers/firmware | |
| parent | 898ece8e5e5102c627f8f2ef26d281f71b439169 (diff) | |
| download | lwn-ffb709e6aa95c3ba44fa8af9f7815e3c6cfed04e.tar.gz lwn-ffb709e6aa95c3ba44fa8af9f7815e3c6cfed04e.zip | |
pcdp: use early_ioremap/early_iounmap to access pcdp table
commit 6c4088ac3a4d82779903433bcd5f048c58fb1aca upstream.
efi_setup_pcdp_console() is called during boot to parse the HCDP/PCDP
EFI system table and setup an early console for printk output. The
routine uses ioremap/iounmap to setup access to the HCDP/PCDP table
information.
The call to ioremap is happening early in the boot process which leads
to a panic on x86_64 systems:
panic+0x01ca
do_exit+0x043c
oops_end+0x00a7
no_context+0x0119
__bad_area_nosemaphore+0x0138
bad_area_nosemaphore+0x000e
do_page_fault+0x0321
page_fault+0x0020
reserve_memtype+0x02a1
__ioremap_caller+0x0123
ioremap_nocache+0x0012
efi_setup_pcdp_console+0x002b
setup_arch+0x03a9
start_kernel+0x00d4
x86_64_start_reservations+0x012c
x86_64_start_kernel+0x00fe
This replaces the calls to ioremap/iounmap in efi_setup_pcdp_console()
with calls to early_ioremap/early_iounmap which can be called during
early boot.
This patch was tested on an x86_64 prototype system which uses the
HCDP/PCDP table for early console setup.
Signed-off-by: Greg Pearson <greg.pearson@hp.com>
Acked-by: Khalid Aziz <khalid.aziz@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/pcdp.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/firmware/pcdp.c b/drivers/firmware/pcdp.c index 51e0e2d8fac6..a330492e06f9 100644 --- a/drivers/firmware/pcdp.c +++ b/drivers/firmware/pcdp.c @@ -95,7 +95,7 @@ efi_setup_pcdp_console(char *cmdline) if (efi.hcdp == EFI_INVALID_TABLE_ADDR) return -ENODEV; - pcdp = ioremap(efi.hcdp, 4096); + pcdp = early_ioremap(efi.hcdp, 4096); printk(KERN_INFO "PCDP: v%d at 0x%lx\n", pcdp->rev, efi.hcdp); if (strstr(cmdline, "console=hcdp")) { @@ -131,6 +131,6 @@ efi_setup_pcdp_console(char *cmdline) } out: - iounmap(pcdp); + early_iounmap(pcdp, 4096); return rc; } |