kumquat-buildroot/package/qemu/0003-target-arm-arm-semi-fix-SYS_OPEN-to-return-nonzero-f.patch
Romain Naour 58af9a70cc package/qemu: remove csky fork
We have a qemu fork for csky cpus [1] but since qemu version
bump to 4.2.0 [2] and libssh2/libssh change the csky build is
broken.

The csky fork is based on Qemu 3.0.0 but unlike autotools packages
any unknown option is handled as error.

Since we don't want to support all options from previous qemu
release and the github repository has been removed [3] and the
only remaining archive is located on http://sources.buildroot.net,
remove the qemu csky fork as suggested by [4].

[1] https://git.buildroot.net/buildroot/commit/?id=f816e5b276f1ef15840bec6667f1e8219717ab7d
[2] https://git.buildroot.net/buildroot/commit/?id=0ea17054ce7dfc54efca5634133cef786445e7b1
[3] https://github.com/c-sky/qemu
[4] http://lists.busybox.net/pipermail/buildroot/2020-May/281885.html

Signed-off-by: Romain Naour <romain.naour@gmail.com>
Cc: Guo Ren <ren_guo@c-sky.com>
Cc: Peter Korsgaard <peter@korsgaard.com>
[Peter: move patches out of 4.2.0 subdir]
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2020-05-25 22:52:53 +02:00

79 lines
2.8 KiB
Diff

From 318f83f387678a3c0a2a729b506613011c6830b2 Mon Sep 17 00:00:00 2001
From: Masahiro Yamada <masahiroy@kernel.org>
Date: Fri, 17 Jan 2020 14:09:30 +0000
Subject: [PATCH] target/arm/arm-semi: fix SYS_OPEN to return nonzero
filehandle
According to the specification "Semihosting for AArch32 and Aarch64",
the SYS_OPEN operation should return:
- A nonzero handle if the call is successful
- -1 if the call is not successful
So, it should never return 0.
Prior to commit 35e9a0a8ce4b ("target/arm/arm-semi: Make semihosting
code hand out its own file descriptors"), the guest fd matched to the
host fd. It returned a nonzero handle on success since the fd 0 is
already used for stdin.
Now that the guest fd is the index of guestfd_array, it starts from 0.
I noticed this issue particularly because Trusted Firmware-A built with
PLAT=qemu is no longer working. Its io_semihosting driver only handles
a positive return value as a valid filehandle.
Basically, there are two ways to fix this:
- Use (guestfd - 1) as the index of guestfs_arrary. We need to insert
increment/decrement to convert the guestfd and the array index back
and forth.
- Keep using guestfd as the index of guestfs_array. The first entry
of guestfs_array is left unused.
I thought the latter is simpler. We end up with wasting a small piece
of memory for the unused first entry of guestfd_array, but this is
probably not a big deal.
Fixes: 35e9a0a8ce4b ("target/arm/arm-semi: Make semihosting code hand out its own file descriptors")
Cc: qemu-stable@nongnu.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200109041228.10131-1-masahiroy@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
(cherry picked from commit 21bf9b06cb6d07c6cc437dfd47b47b28c2bb79db)
Signed-off-by: Adrien Grassein <adrien.grassein@smile.fr>
Signed-off-by: Romain Naour <romain.naour@smile.fr>
---
target/arm/arm-semi.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c
index 6f7b6d801b..4275dfc345 100644
--- a/target/arm/arm-semi.c
+++ b/target/arm/arm-semi.c
@@ -144,7 +144,8 @@ static int alloc_guestfd(void)
guestfd_array = g_array_new(FALSE, TRUE, sizeof(GuestFD));
}
- for (i = 0; i < guestfd_array->len; i++) {
+ /* SYS_OPEN should return nonzero handle on success. Start guestfd from 1 */
+ for (i = 1; i < guestfd_array->len; i++) {
GuestFD *gf = &g_array_index(guestfd_array, GuestFD, i);
if (gf->type == GuestFDUnused) {
@@ -168,7 +169,7 @@ static GuestFD *do_get_guestfd(int guestfd)
return NULL;
}
- if (guestfd < 0 || guestfd >= guestfd_array->len) {
+ if (guestfd <= 0 || guestfd >= guestfd_array->len) {
return NULL;
}
--
2.24.1